novato, ca 94945 - vision...

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cc15_078

STAFF REPORT

MEETING

DATE: May 5, 2015

TO: City Council

Novato Public Finance Authority Board

FROM: Russ Thompson, Public Works Director

Tony Williams, Senior Civil Engineer

SUBJECT: ADOPT RESOLUTIONS APPROVING THE HAMILTON FIELD LEVEE

SYSTEM OPERATIONS & MAINTENANCE MANUAL AND FINDING

SAID ACTION EXEMPT FROM THE REQUIREMENTS OF THE

CALIFORNIA ENVIRONMENTAL QUALITY ACT (CEQA),

PURSUANT TO CEQA GUIDELINES SECTION 15301

REQUEST

Consider adopting resolutions approving the Hamilton Field Levee System Operations &

Maintenance Manual (O&M Manual).

RECOMMENDATION

Adopt resolutions.

DISCUSSION

Brief Levee History and Background

Construction of Hamilton Field levee embankment began in late 1995 as part of the redevelopment

of the former Hamilton Field Army Airfield. Final construction was completed June 1997. On June

10 of that year, the original maintenance plan and operations manuals for the levee and the

Hamilton Storm Water pump station were adopted. The levee system and pump stations are owned

partially by the City and partially by the Novato Public Finance Authority (NPFA) and are

maintained through the Hamilton Community Facilities District (CFD). In April of last year, the

former Outer/Outboard San Pablo Bay Levee was breached to allow tidal connection of the

Hamilton Wetlands Restoration Project with San Pablo Bay. This marked the first time since the

levee system was built that it truly served a flood control/protection function by directly protecting

the area from the waters of San Pablo Bay.

The “Levee System” includes the 1.4 mile-long earthen levee embankment; a partial seepage

collection system; a concrete masonry splash/wave run-up wall; two storm water pump stations

and their outfall structures; and the interior storm drainage system on the developed landside of

the levee embankment. The levee system provides flood protection for approximately 536

privately and publicly owned buildings and associated infrastructure. The levee system also

922 Machin Avenue Novato, CA 94945

(415) 899-8900 FAX (415) 899-8213

www.novato.org

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provides drainage collection from a large portion of the Hamilton area east of the Pacheco Creek

watershed. The system provides for the subsequent stormwater discharge to adjacent San Pablo

Bay. The O&M Manual replaces the original outdated maintenance manual and related documents

developed as part of the initial levee construction and Hamilton site development in the mid-1990s.

Federal Agency Oversight

There are two key federal agencies that regulate levee systems: Federal Emergency Management

Agency (FEMA) and the US Army Corps of Engineers (USACE). An accredited levee system is

a system that FEMA has determined can be shown on a Flood Insurance Rate Map (FIRM) as

providing a 1-percent-annual-chance or greater level of flood protection (previously known as a

“100-year flood”). This determination is based on the submittal of data and documentation

required by 44 CFR Section 65.10. The area landward of an accredited levee system is shown as a

moderate-risk area, labeled Zone X (shaded), on the FIRM except for areas of residual flooding,

such as ponding areas, which will be shown as high-risk areas, called Special Flood Hazard Areas

(SFHAs).

The USACE Levee Safety Program works to better understand, manage, and reduce the flood risks

associated with levees. USACE maintains a national inventory of levee systems and makes the

information available in the National Levee Database. They inspect and assess about 2,500 levee

systems nationwide, and use the data to prioritize action. Recognizing that managing risk is a

shared responsibility, USACE works closely with federal, state, local and international partners to

share information and develop solutions. The USACE has primary authority for the repair of flood

control works under the Flood Control and Coastal Emergency Act, Public Law (PL) 84-99 (33

U.S.C. 701n) and Title 33: Navigation and Navigable Waters. The USACE Rehabilitation and

Inspection Program (RIP) provides for the inspection and rehabilitation of Federal and non-Federal

flood control projects. To be eligible for rehabilitation assistance following a disaster, a flood

control work must have a public sponsor; be regularly maintained through an Operations &

Maintenance Manual, and have an Active RIP status prior to the disaster event. Under the program,

USACE can provide flood fighting assistance to applicants during a flood event.

History of Levee Accreditation

A Conditional Letter of Map Revision was issued by FEMA in 1995 as the levee was being

designed and constructed. A Letter of Map Revision (LOMR) was issued on June 13, 1997 and

the subsequent FIRM maps showed a 1-percent-annual chance flood protection inboard of the

levee. On September 26, 2007, FEMA issued a letter re-accrediting the levee for a 1-percent-

annual chance flood protection.

In 2012 FEMA conducted detailed coastal engineering analyses and mapping of the San Francisco

Bay shoreline within the nine San Francisco Bay Area counties. The analysis and mapping revised

and updated the flood and wave data for the Marin County Flood Insurance Study (FIS) report and

forty-nine FIRM panels along the San Francisco Bay shoreline. On March 24, 2014 the

Preliminary Flood Insurance Study and the Preliminary Flood Insurance Rate Maps were received

by the City. FEMA has posted digital copies of the revised FIRM panels, FIS report, and Digital

FIRM database to the following website:

https://hazards.fema.gov/femaportal/prelimdownload/

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https://hazards.fema.gov/femaportal/prelimdownload/

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FEMA is expected to issue final FIRMs in September 2015 which will show a new base flood

elevation of 10 feet NAVD near and around the Hamilton levee area. When FEMA issues

preliminary DFIRM updates that affect the area around the levee system, re-accreditation of the

levee may be required. Levee re-accreditation should be completed prior to the final issuance of

updated FIRMs. The elements of the accreditation process under 44 CFR Section 65.10 includes

freeboard requirements, embankment protection, stability and settlement criteria, interior drainage,

and operations and maintenance plans.

Levee System Maintenance

FEMA regulations require levee systems be maintained in accordance with an officially adopted

maintenance plan, and a copy of this plan must be provided to FEMA by the owner of the levee

system when recognition is being sought or when the plan for a previously recognized system is

revised in any manner. All maintenance activities must be under the jurisdiction of a Federal or

State agency, an agency created by Federal or State law, or an agency of a community participating

in the NFIP that must assume ultimate responsibility for maintenance. The plan must document

the formal procedure that ensures that the stability, height, and overall integrity of the levee and

its associated structures and systems are maintained. At a minimum, the plan shall specify the

maintenance activities to be performed, the frequency of their performance, and the person by

name or title responsible for their performance. In order to be eligible for the USACE Levee Safety

program, a levee System O&M Manual must be established to comply with these requirements.

The O&M Manual provides a comprehensive guideline and reference for all aspects of the levee

system’s Operations and Maintenance (O&M), including emergency operations. The O&M

Manual comprises ten sections with topics ranging from regulatory requirements to private

property owner responsibilities. Routine, periodic, and annual inspection procedures and forms are

included and are provided to assist Public Works maintenance and engineering personnel with

important checklists to ensure the proper condition and function of the system. The O&M Manual

will be used by personnel responsible for the levee system operations and maintenance; capital

improvement project development; public outreach efforts; and emergency response specific to

the levee system.

The O&M Manual is designed to be a living document and will be updated periodically through

amendments or revisions as site conditions evolve and modifications to the levee system operations

and maintenance are required. In addition, state and federal regulations regarding levees may

change over time triggering a need to update the Manual. The Manual will be thoroughly reviewed

every five years and revisions made as necessary based on that review cycle.

ENVIRONMENTAL ASSESSMENT

The Hamilton Field Levee System O&M Manual is exempt from the requirements of the California

Environmental Quality Act (CEQA), pursuant to CEQA Guidelines Section 15301, Existing

Facilities. The O&M Manual describes the operations, maintenance, and inspection policies, and

procedures for the existing levee system, including pump stations, the levee embankment, the levee

splash/wave run-up wall, seepage collection and landside drainage system. The O&M Manual

provides City staff with comprehensive guidance to properly operate and maintain the levee system

in accordance with FEMA and other agency standards.

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FISCAL IMPACT

Levee operations and maintenance is funded through the Hamilton Field CFD. No fiscal impact is

imposed by adopting this O&M Manual.

ALTERNATIVES

No other options for achieving compliance with the FEMA/NFIP requirements for the levee

accreditation have been identified.

ATTACHMENTS

1. Hamilton Levee System O&M Manual (appendices available in the City Clerk’s Office)

2. City Council Resolution adopting the Hamilton Field Levee System O&M Manual

3. NPFA Board Resolution adopting the Hamilton Field Levee System O&M Manual

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HAMILTON FIELD LEVEE SYSTEM

OPERATIONS AND MAINTENANCE (O&M)MANUALPrepared byPublic Works DepartmentForCity of Novato Hamilton Field Community Facilities District No. 1994-1August 2014

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HamiltonFieldLeveeSystemOPERATIONSANDMAINTENANCE(O&M)MANUALImplementation by:

City of Novato Hamilton Field Community Facilities District No. 1994-1

Responsibility to Operate and Maintain:

City of Novato Hamilton Field Community Facilities District No. 1994-1

Date Created:

August 2014

Amendments

This is a living document and may need to be updated over the course of the time as siteconditions or regulatory requirements changes. Use Appendix A for documenting revisions.

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Hamilton Field Levee O&M2014

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HamiltonFieldLeveeSystemIMPORTANTQUICKREFERENCEINFORMATIONProject Name: Hamilton Field Levee System

Identification Number: reserved for National Levee Database, FEMA #, state database

Water Body: San Pablo Bay

Project Location: Northern Extent: N38.064504°, W122.518884° (Sta. 72+00); SouthernExtent: N38.050576°, W122.510976° (Sta. 1+50, end of Hangar Avenue) Novato, California

City/County: Novato, Marin County, California

Owner: City of Novato; Novato Public Finance Authority (NPFA)

State Jurisdiction: The California Governor's Office of Emergency Services (Cal OES)

FEMA Region: Region IX, Oakland, CA

USACE District: San Francisco District, San Francisco, CA

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Official Adoption

Insert Council Resolution adopting this manual

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Table of Contents Page

1.0 INTRODUCTION AND PURPOSE ........................................................................................... 1

1.1 Introduction...................................................................................................................... 1

1.2 Purpose of This Manual.................................................................................................... 1

1.3 Previous Existing Documents ........................................................................................... 1

1.4 Technical Reference ......................................................................................................... 2

1.5 Manual Amendments and Revisions................................................................................ 3

2.0 LEVEE SYSTEM DESCRIPTION AND HISTORY........................................................................ 4

2.1 Levee System Description Summary ................................................................................ 4

2.1.1 Levee Embankment .................................................................................................. 4

2.1.2 Seepage Control........................................................................................................ 5

2.1.3 Wave Run-up and Splash Wall .................................................................................. 9

2.1.3 Interior Drainage..................................................................................................... 10

2.1.4 Pump Stations ......................................................................................................... 10

2.2 Geotechnical and Engineering Analysis ......................................................................... 14

2.3 Hamilton Wetlands Restoration Project ........................................................................ 15

2.4 San Francisco Bay Trail ................................................................................................... 17

3.0 REGULATORY CERTIFICATION AND ACCREDITATION ........................................................ 18

3.1 FEMA Accreditation History ........................................................................................... 18

3.2 FEMA Map Actions and Re-Accreditation...................................................................... 19

3.2.1 Design Criteria......................................................................................................... 19

3.2.2 Operations Plan....................................................................................................... 20

3.2.3 Interior Drainage Plan............................................................................................. 20

3.2.4 Adopted Maintenance Plan .................................................................................... 20

3.2.5 Certification............................................................................................................. 21

3.3 Community Rating System (CRS).................................................................................... 21

3.4 Federal Rehabilitation Assistance .................................................................................. 22

3.5 Compliance with Environmental and Historic Preservation Requirements .................. 23

4.0 LEVEE SYSTEM INSPECTION PROGRAM............................................................................. 24

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4.1 General Procedures........................................................................................................ 24

4.2 Routine Inspections........................................................................................................ 24

4.3 Annual Inspection........................................................................................................... 25

4.3.1 Inspection Ratings ........................................................................................................ 25

4.4 Elevation Surveys ........................................................................................................... 26

4.4.1 Seal Level Rise ......................................................................................................... 27

4.5 Special Inspections ......................................................................................................... 28

4.5.1 Localized Seepage ................................................................................................... 28

4.5.2 Pre and Post Storm Events...................................................................................... 29

4.5.3 Post Disaster Events................................................................................................ 29

5.0 INTERIOR DRAINAGE PLAN ................................................................................................ 30

5.1 Overview ........................................................................................................................ 30

5.2 Pump Stations ................................................................................................................ 32

5.2.1 Hamilton Pump Station #1...................................................................................... 33

5.2.2 Bayside Pump Station #2 ........................................................................................ 34

5.2.3 Supervisory Control and Data Acquisition (SCADA)................................................ 35

5.3 Storm Drainage Network ............................................................................................... 37

5.4 Interior Drainage Analysis .............................................................................................. 38

5.5 Pump Station Inspections............................................................................................... 39

5.5.1 Daily Checks ............................................................................................................ 39

5.5.2 Monthly Inspections ............................................................................................... 39

5.5.3 Annual Inspections.................................................................................................. 43

5.6 Pump Station Maintenance............................................................................................ 43

5.7 Storm Drainage Inspection............................................................................................. 44

5.8 Flood Warning System ................................................................................................... 44

6.0 LEVEE SYSTEM MAINTENANCE PLAN................................................................................. 46

6.1 Vegetation Management ............................................................................................... 46

6.2 Animal Control ............................................................................................................... 46

6.3 Levee Drainage Ditches .................................................................................................. 47

6.4 Levee Toe Drains ............................................................................................................ 47

6.5 Levee Crown Maintenance ............................................................................................ 47

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6.6 Splash Wall Maintenance and Repair ............................................................................ 48

6.7 Levee Banks and Revetment .......................................................................................... 49

6.7.1 Seepage................................................................................................................... 49

6.7.2 Embankment Protection......................................................................................... 49

6.8 Levee Wall Closure ......................................................................................................... 50

6.9 Storm Drainage Maintenance ........................................................................................ 50

7.0 EMERGENCY PROCEDURES ................................................................................................ 51

7.1 Purpose and Organization.............................................................................................. 51

7.2 Preliminary Response Activities ..................................................................................... 51

7.3 Post Event Recovery....................................................................................................... 52

7.5 Emergency Preparedness and Training.......................................................................... 52

8.0 SITE SECURITY .................................................................................................................... 54

8.1 Specific Security Measures.................................................................................................. 55

9.0 TRAINING ........................................................................................................................... 56

9.1 Levee System Training Requirements ............................................................................ 56

9.2 Emergency Training........................................................................................................ 56

10.0 COMMUNITY OUTREACH................................................................................................... 57

10.1 Property Owner Responsibilities.................................................................................... 57

10.1.1 Area Drain Maintenance......................................................................................... 57

10.1.2 Vegetation Management ........................................................................................ 57

10.1.3 Social Trails on Levee Embankment ....................................................................... 58

10.2 City’s Responsibility........................................................................................................ 58

10.3 Seepage Observations and Notifications ....................................................................... 59

AppendicesA Amendments/Revisions FormB As-built Records: Levee Embankment and Pump StationsC As-built Records: Levee Raising ProjectD As-built Records: Wall Closure GateE FEMA Accreditation September 2007F Certification of Compliance with Environmental and Historic Preservation Requirements

for Levee Maintenance, Form CC-620EHP

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Appendices (con’t)

G Levee System Periodic or Special Inspection FormH Annual Inspection ChecklistI Levee Elevation Survey FormJ Pump Station Inspection FormsK Wall Closure Gate Shop Drawings and Manufacturer InformationL Training Record Form

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1.0 INTRODUCTION AND PURPOSE

1.1 IntroductionThe Hamilton Field Levee System is comprised of an earthen levee embankment, a concrete

1.2 Purpose of This ManualThe purpose of this Manual is to provide a comprehensive guideline and reference for allaspects of the levee system’s Operations and Maintenance (O&M), including emergencyoperations. This O&M Manual replaces the original maintenance manual and relateddocuments developed as part of the initial levee construction and site development in the mid-1990s. The O&M Manual comprises ten sections with topics ranging from regulatoryrequirements to private property owner responsibilities. Routine, periodic, and annualinspection procedures and forms are included and are provided to assist maintenance andengineering personnel with important checklist to ensure the proper condition and function ofthe system.

masonry splash wall, a splash wall closure gate, two storm water pump stations, and an interiordrainage network. The Levee System protects residential subdivisions, park and recreationfacilities, businesses, the U.S. Coast Guard Pacific Strike Team facility, and the associated publicright-of-way improvements from the waters of the adjacent San Pablo Bay. See the LeveeSystem Site Map in Section 2 for the location of the system features. The City of Novato’sHamilton Field Community Facility District No. 1994-1 (here after referred to as “HamiltonCFD”) is responsible for day-to-day operations and maintenance. Designated Public Workspersonnel from the Maintenance Division provide the required operation and maintenance.The Public Works Engineering Division provides technical support and engineering as required.

1.3 Previous Existing DocumentsPreviously prepared levee-related documents and manuals were reviewed during thedevelopment of this manual. Many of the previously prepared documents were prepared aspart of the original levee construction and do not accurately reflect the current systemconfiguration or the day-to-day city maintenance activities. Other documents used include

Throughout this O&M Manual, referenced is made to Public Works or City personnel in lieu ofHamilton CFD personnel since designated City personnel are assigned with specific the leveesystem operations and maintenance under the provisions of the Hamilton CFD. The O&MManual should be used by City personnel responsible for the levee system operations andmaintenance; capital improvement project development; public outreach efforts; andemergency response specific to the levee system. The O&M Manual is not designed to serve any other purpose other than providing standard operating and maintenance procedures fordesignated City staff.

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manufacturer data and product manuals. A partial list of these documents include thefollowing:

Hamilton Field Flood Control Levee Inspection, Monitoring, and Maintenance Manual, HamiltonField, Phase I, undated (circa 1997), by Geomatrix Consultants

Emergency Response Plan Flood Control Levee Hamilton Field, Phase I, May 22, 1997, GeomatrixConsultants

Hamilton Field Tentative Map Phase I, Report, May 25, 1993 (Revised June 22, 1993), byCSW/Stuber-Stroeh Engineering Group, Inc.

Final Hamilton Field Lots 1 & 2 Preliminary Design Report for Storm Water Pump Station, August15, 1997, CSW/Stuber-Stroeh Engineering Group, Inc.

As-built Record Drawings: Hamilton Field Improvement Plans/Levee Grading Plans (10/1997),Hamilton Field Improvement Plans/Storm Water Pump Station (10/1997); BaysideSubdivision/Storm Drain Pump Station (6/2001).

Operations and Maintenance Manuals: Hamilton Field Storm Water Pump Station (multi-volume set); City of Novato Bayside Subdivision Storm Water Pump Station (multi-volume set)(O&M Manuals are on file at each pump station and the Corporation Yard)

Wonderware Software Support Information (on file at Corporation Yard)

Trio Datacom J-Series Ethernet Radio User Manual (on file at Corporation Yard)

1.4 Technical ReferenceSeveral technical and regulatory documents and publications were used to develop thisManual. The key documents include the following:

Code of Federal Regulations, Title 44 Emergency Management and Assistance, Part 65.10Mapping of areas protected by levee systems (44 CFR 65.10)

Levee Owner’s Manual for Non-Federal Flood Control Works, The Rehabilitation and InspectionProgram, Public Law 84-99, March 2006, US Army Corps of Engineers (USACE)

USACE Process for the National Flood Insurance Program (NFIP) Levee System Evaluation, EC1110-2-6067, August 2010, US Army Corps of Engineers

Interim Policy for Determining Eligibility Status of Flood Risk management Projects for theRehabilitation Program Pursuant to Public Law (P.L.) 84-99, Memorandum March 21, 2014,USACE

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National Flood Insurance Program Community Rating System Coordinator’s Manual FIA-15/2013, Federal Emergency Management Agency

Emergency Preparedness Guidelines for Levees, A Guide for Owners and Operators, 2012,Federal Emergency Management Agency

The Recommendations for National Levee Safety Standards, National Committee on LeveeSafety 2011

Urban Levee Design Criteria, May 2012, California Department of Water Resources

National Flood Insurance Program Community Rating System Coordinator’s Manual FIA-15/2013, Federal Emergency Management Agency

City of Novato General Plan 2035 Policy White Paper Sea Level Rise and Adaptation, DraftJanuary 2014

City of Novato Emergency Operations Plan (May 2009)

1.5 Manual Amendments and RevisionsThis Manual may require amendments or revisions as site conditions evolve and modificationsto the levee system operations and maintenance are required. In addition, state and federalregulations regarding levees may change over time triggering a need to update this Manual.The Manual should be thoroughly reviewed every five years and revisions made as necessarybased on that review cycle.

The Amendment Log and Periodic Review Log forms in Appendix A is provided to documentamendments or revisions and the 5-year review of this Manual.

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2.0 LEVEE SYSTEM DESCRIPTION AND HISTORY

2.1 Levee System Description SummaryThe Hamilton Field Levee system consists of an earthen levee embankment; a seepagecollection system; a concrete masonry splash/wave run-up wall; two storm water pumpstations and their outfall structures; and the interior drainage system on the landside of thelevee embankment. The levee system provides flood protection for approximately 536 privatelyand publicly owned buildings and associated infrastructure. The levee system also providesdrainage collection from a small watershed east of the Pacheco Creek watershed and thesubsequent discharge to San Pablo Bay.

A more detailed description and history of the levee system components are provided in thenext subsections. As-built records of the levee embankment, the pump stations, and theseepage collection system are provided in Appendix B

2.1.1 Levee EmbankmentThe levee embankment is of earthen fill construction measuring approximately 7,543 feet inlength. The embankment ties into existing natural topographic features at the southern andnorthern limits. In addition to the main earthen levee embankment, a reinforced concretemasonry unit (CMU) splash wall is present on the outboard edge of the levee crown. The splashwall extends 3 to 4 feet above the crown elevation (see Section 2.1.3). The crown of the levee

serves as an access andservice road for the CityPublic Works personnel, andconsists of compactedaggregate base course. Thelandside embankment slopevaries from approximately3:1 (horizontal:vertical) inthe lower portions of theembankment to 2:1 in theupper six feet of height. Thewater side of theembankment was originallyconstructed at a 3:1 slopewith rip rap protection

extending from the levee toe to the base of the CMU wall. The rip rap generally consists ofCaltrans No. 2 Backing size rock. In 2012, a segment of the San Francisco Bay Trail was

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constructed (USACE Hamilton Wetland Restoration Project) along the majority of the watersideof the levee embankment (See Section 2.4).

The City of Novato’s CIP Project Number 00-013 raised the crown of the levee by approximately3.5 feet in 2007. The levee crown was raised to account for the future anticipated settlementwhile maintaining 100-year flood protection. In addition, the CMU splash wall was raisedapproximately 4 feet. The project was completed and accepted by the City in September 2007.Based on the most recent elevation surveys (2014, White and Prescott; City of Novato), thelevee crown is at an average elevation of 12.14 feet NAVD88 (North American Vertical Datum of1988). For purposes of referencing survey locations, as well as other locational reference, alinear stationing has been established for the levee alignment. The earthen embankment runsfrom Station 0+00 (southern beginning point) to Station 75+43 (northern end point). A leveestationing map is presented at the end of this subsection.

A copy of the levee raising plans (CIP No. 00-013) is provided in Appendix C.

The landside areas adjacent to the levee are development as either residential single-familyhomes or commercial buildings, and associated parking lots. The U.S. Coast Guard occupies a6.8 acres parcel near the middle portion of the levee alignment. Construction of leveeembankment began in late 1995 as part of the redevelopment of the former Hamilton FieldArmy Airfield. Final construction was completed June 1997. On June 10 on that year, the CityCouncil of Novato approved and adopted the Maintenance Plan and Operations Manuals forthe levee and pump station. The City’s Hamilton CFD was created in 1994 and has beenmaintaining and operating the levee system since 1997.

2.1.2 Seepage ControlAs part of the original construction, a seepage cut-off trench was constructed beneath and nearthe outboard toe of the levee to prevent bay water retained by the levee from seeping throughthe pervious fill material that underlies the levee. Where the levee was constructed onconcrete pavement (old airfield infrastructure), the pavement was removed for a distance of 12feet in from the outboard toe of the levee and the barrier was installed along the edge of thepavement. Where the levee was constructed on soil foundation, the seepage barrier wasinstalled beneath the center of the levee. The 2.5-foot wide trench was excavated through theoverlying fill to at least 2 feet into the underlying deposit of soft silty clay (Bay Mud). The trenchis generally 5 to 10 feet deep and backfilled with impervious soil.

Despite the consideration for seepage control in the original levee design and construction,evidence of seepage at select locations was discovered by residents and city staff in early 2008.The seepage observations were coincident with the primary construction phase of the HamiltonWetlands Restoration project which included the hydraulic placement of several million tons of

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dredged material (sediments consisting primarily of sands and silts). The hydraulic placementmethods resulted in a hydraulic slurry that was an approximate mixture of 80% water and 20%sediments. The observed seepage was partly associated with old utility lines (duct banks, stormdrains, etc.) that were not known or overlooked at the time of the levee construction.

In response to the observed and documented seepage, the City awarded CIP Project No. 09-014in the summer of 2009. The project constructed seepage toe drains and collection structures atselect locations along Hangar Avenue and plugged (grouted) old utility lines that were allowingthe passage of water under the levee. The collection structures are similar to storm drain inletstructures. Perforated pipe drains collect seepage water in a lateral direction (along the leveetoe) as well as directly next to the structures where the old utilities were present.

A total of approximately 940 feet of 8-inch diameter perforated pipe (toe drain) runs betweenthe “Site 2A” collection box and the “Site 3” collection box. In addition, solid 12-inch pipe alsoconnects the boxes. The pipes run in the same alignment as the v-ditch in this area and twoinlet structures in the v-ditch alignment distribute the collected water to the existing stormdrain system in the Hamilton Landing subdivision (Audubon Way). Another 245 feet of toe drainwas installed between 114 and 126 Emerson Avenue, along the levee toe, next to the concretev-ditch.

The figures on the following pages provide construction details and locations of the seepage collection devices.

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Typical Seepage Collection Structure Detail

Typical Seepage Collection Toe Drain

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Seepage Collection Sites (CIP 09-014)

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In 2011, an additional toe drain was added along the levee toe parallel to Emerson Avenue. Thetoe drain extends northeast and connects/terminates at an existing storm drain inlet adjacentto 190 Emerson Avenue as shown below.

Additional Toe Drain on Emerson Avenue (2011)

2.1.3 Wave Run-up and Splash WallAs previously described, a steel reinforced and grout-filled CMU splash wall (also referred to asa flood wall) is present on the outboard (water side) edge of the levee crown. The top of thewall varies in height but is generally 3 feet above the crown elevation. The wall was constructedin 25-foot wide sectional panels supported by 16-inch diameter drilled concrete reinforcedpiers spaced approximately 8 feet apart. The piers extend 7.5 feet below the original crownelevation (+8.0 NGVD29). The joints between each panel are offset and are sealed with a foambacker and a surface caulking.

(E) Inlet

Emerson Avenue

Additional Toe Drain

Moore Road

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2.1.3.1Wall Closure GateIn July 2014, a swing gate was installed in the splash wall to allow ADA access to the new San

Francisco Bay Trail on theimmediate waterside of thelevee. The gate wasdesigned and installed toensure full closure andprotection from flooding.The gate is normally lockedin the open position asshown in the photo on theleft. During severe stormevents, emergencyprocedures include the needto close the gate. SeeSections 6 and 7 for moreinformation regarding

maintenance and emergency procedures.

The wall closure gate as-built drawings are provided in Appendix D.

2.1.3 Interior DrainageThe interior drainage system consists of a storm drainage collection and conveyance networkand two storm water pump stations. The storm drainage collection system consists primarily ofroadway catch basins and inlets, and associated collection and distribution piping. Otherdrainage collection consists of concrete v-ditches within the surrounding hillslopes and atportions of the inboard (land side) toe of the levee. The majority of the single family homeswithin the various Hamilton subdivisions have yard drains that collect runoff from roofdownspouts and area drains that are connected to the storm drainage system. Similarly, thecommercial development within the area have similar drainage systems. See Section 5.0 formore information.

2.1.4 Pump StationsThe levee system provides flood protection for several subdivisions, businesses, and municipaland federal government property on the land side of the levee. The interior drainage in thisarea is routed through storm drain pipes to two storm drain pump stations that discharge tothe San Pablo Bay on the water side of the levee. Pump Station #1 (also referred to as theHamilton Pump Station) is located at the south end of the levee embankment; and Pump

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Station #2 (also referred to as the Bayside Pump Station) is located near the northern end ofthe levee embankment.

Pump Station #1 is located on a parcel owned by the Novato Public Finance Authority (NPFA)and Pump Station #2 is located on a city-owned parcel. Both stations have access from citystreets. Pump station operations can be monitored and controlled remotely through the city’sSCADA (supervisory control and data acquisition) system. More detailed information on thepump stations is provided in Section 5.2.

A Levee System Site Map and Levee Stationing Diagram are provided on the following pages

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Hamilton Levee System Site Map

PUMP STATION #2

PUMP STATION #1

LEVEE EMBANKMENT

CLOSURE GATE

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Levee Stationing:

35+00 = 3,500 feet of length measured from 0+00

Station 0+00 begins at Pump Station #1

Station 2+20 - Start of levee access road at southern end

Station 75+43 – end of levee embankment at northern end

Station 45+60 – wall closure gate

Southgate Subdivision

Bayside Subdivision

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2.2 Geotechnical and Engineering AnalysisSeveral geotechnical engineering evaluations and studies have been performed since theoriginal design phase of the levee system to the present (2104). A summary of the studies andreports is listed below:

1. Geomatrix Consultants, Geotechnical Engineering Study – Hamilton Field Phase 1Development, Novato, California, Volume 1, 12 June 1995a.

2. Geomatrix Consultants, Letter to Mr. Todd Wright (The New Hamilton Partnership)regarding “Response to HLA Review Comments, Hamilton Field Phase 1 Development, Novato,California”, 2 October 1995b.

3. Geomatrix Consultants, “Flood Control Levee Inspection, Monitoring, and MaintenanceManual, Hamilton Field, Phase 1, Novato, CA” 21 February 1997.

4. Geomatrix Consultants, Emergency Response Plan – Flood Control Levee, Hamilton FieldPhase 1, Novato, California 22 May 1997.

5. Geomatrix Consultants, Letter to Mr. Todd Wright (The New Hamilton Partnership)regarding “Construction of Flood Control Levee, Hamilton Field Phase 1, Novato, California”, 11March 1998a.

6. Geomatrix Consultants, Letter to Mr. Todd Wright (The New Hamilton Partnership)regarding “Evaluation of Effect of Placing Fill Against the Flood Control Levee, Hamilton FieldPhase 1, Novato, California”, 2 April 1998b.

7. URS, “Responses to Review Comments – Draft Report; New Hamilton PartnershipLevee”, Letter to U.S. Army Corps of Engineers, dated 19 August 2003.

8. URS, “Final Report: Geotechnical Investigation and Design Recommendations for theNew Hamilton Partnership Levee, Hamilton Army Air Field, Wetlands Restoration Project”, 30April 2004.

9. URS/ARUP, “Final Report: Test Fill Construction, Monitoring, and Evaluation – HamiltonWetlands Restoration Project – Part I: Performance During Construction”, 19 September 2005a.

10. URS/ARUP, “Final Report: Test Fill Construction, Monitoring, and Evaluation – Part II:Performance After Construction – Six Month Monitoring Program – Hamilton WetlandsRestoration Project”, December 2005b.

11. ARUP, “Final Report: Numerical Analysis of Proposed Revised Design of SeasonalWetland Fill Along the Existing NHP Levee, Hamilton Wetlands Restoration Project”, 6 March2006.

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12. Geomatrix Consultants, Letter to Mr. Glenn Young (City of Novato), “Geotechnical PeerReview, Test Fill Construction and Monitoring Program, Hamilton Wetlands Restoration Project,Novato, CA”, 3 April 2006.

13. USACE, “Hamilton Wetlands Restoration Project – Project Information ReportEngineering and Construction Adjacent to the Novato Public Finance Authority Levee (NPFALevee)”, 24 November 2008.

14. USACE, Letter to Mr. Glenn Young, “Seepage and Slope Stability Analysis”, 18 December2008.

15. Geosyntec Consultants, Letter to Mr. Jeffrey Walter (City Attorney, City of Novato)regarding “Evaluation of Levee Seepage Sources, Based on Review of Design and ConstructionDocuments”, February 5, 2009.

16. USACE, “Hamilton Wetlands Restoration Project – Project Information Report 2nd Cityof Novato Easement for Construction Adjacent to the Novato Public Finance Authority Levee(NPFA Levee)”, 12 June 2009.

17. Geosyntec Consultants, “Geotechnical Evaluation of the Hamilton Field Levee, Novato,California”, December 2014

The City’s Engineering Division maintains either a hardcopy or electronic copies of thesedocuments at the City Administrative Offices at 922 Machin Avenue.

2.3 Hamilton Wetlands Restoration ProjectThe Hamilton Field Levee borders the Hamilton Wetlands Restoration Project (HWRP) to theeast and south. The goal of the HWRP is to create a diverse array of wetland and wildlifehabitats that benefit a number of special status species as well as other migratory and residentspecies. Planning and design for wetland restoration started in the 1990s when closure of theHamilton Army Airfield (HAAF) was considered. Construction of the project began in 2001 withfunding from the Federal Government and the State of California. The U.S. Army Corps ofEngineers (USACE) formed a joint project team with broad participation including the CaliforniaState Coastal Conservancy and the San Francisco Bay Conservation and DevelopmentCommission (BCDC). The site is owned by the California State Coastal Conservancy.

The HWRP is bounded by the levee to the west, diked farmland to the east, Pacheco Pond tothe north, and San Pablo Bay to the east and south. HWRP includes approximately 400 acres oftidal wetlands, 76 acres of seasonal wetlands, and 70 acres of transitional habitat (including thewildlife corridor). Beginning in 2008, dredged material was placed at the HWRP site from thePort of Oakland as part of its deepening and maintenance dredging activities. Several millions of

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cubic yards of hydraulically placed dredged material was used to raise the former airfieldelevations to the required tidal wetland and seasonal wetland elevations.

A long term monitoring plan was implemented in 2014. This plan identifies proposedmonitoring activities, outlines how results from the monitoring will be used to assess projectsuccess and, if needed, adaptively manage the project. The plan specifies who is responsible formonitoring and adaptive management activities.

Hamilton Wetland Restoration Site Map

A brief timeline summary of the project’s construction history is presented below:

2002 Construction of the dredged material off-loader pipeline is completed 2003 - 2007 Demolition of existing buildings and infrastructure within the wetland

footprint; construction of new perimeter levees (Bulge Levee, North Levees (N1 and N2),South Levee) and interior berms.

2008 – 2011 Dredged material from the Port of Oakland Deepening and other projectsis placed hydraulically in the wetland area.

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2012 – 2014 Contouring and shaping of previously placed dredged fill to create innerchannels and other features as well as achieve elevations; construction of the SanFrancisco Bay Trail.

April 2014 Former Outer/Outboard San Pablo Bay Levee breached to allow tidalconnection with San Pablo Bay.

2014 – 2015 Planting and establishment of native plants

2.4 San Francisco Bay TrailA segment of the San Francisco Bay Trail is present on the water side of the levee for themajority of its length. The trail was constructed in 2013 as part of the Hamilton WetlandRestoration Project. The trail consists of a decomposed granite pathway with aggregate baseshoulders, supported by earthen fill that covers the original waterside rip rap slope of the levee.The trail segment borders the levee splash wall and the Hamilton wetlands from approximatelySta. 2+00 to Sta. 65+00. Access to the trail is via the southern extent of the levee off HangarAvenue; an ADA (Americans with Disabilities Act) accessible access point located near Station45+00 (behind 7 Hamilton Landing).

View of SF Bay Trail looking north. Splash/Run-up Wall and levee access road on left

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3.0 REGULATORY CERTIFICATION AND ACCREDITATIONThere are two key federal agencies that regulate levee systems: Federal EmergencyManagement Agency (FEMA) and the US Army Corps of Engineers (USACE). An accredited leveesystem is a system that FEMA has determined can be shown on a Flood Insurance Rate Map(FIRM) as providing a 1-percent-annual-chance or greater level of flood protection. Thisdetermination is based on the submittal of data and documentation required by 44 CFR Section65.10. The area landward of an accredited levee system is shown as a moderate-risk area,labeled Zone X (shaded), on the FIRM except for areas of residual flooding, such as pondingareas, which will be shown as high-risk areas, called Special Flood Hazard Areas (SFHAs).

The USACE Levee Safety Program works to better understand, manage, and reduce the floodrisks associated with levees. USACE maintains a national inventory of levee systems and makethe information available in the National Levee Database. They inspect and assess about 2,500levee systems nationwide, and use the data to prioritize action. Recognizing that managing riskis a shared responsibility, USACE works closely with federal, state, local and internationalpartners to share information and develop solutions.

3.1 FEMA Accreditation HistoryA Conditional Letter of Map Revision was issued by FEMA in 1995 as the levee was beingdesigned and constructed. A Letter of Map Revision (LOMR) was issued on June 13, 1997 andthe subsequent FIRM maps showed a 1-percent-annual chance flood protection inboard of thelevee. On September 26, 2007, FEMA issued a letter re-accrediting the levee for a 1-percent-annual chance flood protection.

Appendix E contains a copy of the most current FEMA accreditation documentation (2007).

In 2012 FEMA conducted detailed coastal engineering analyses and mapping of the SanFrancisco Bay shoreline within the nine San Francisco Bay Area counties. The analysis andmapping revised and updated the flood and wave data for the Marin County Flood InsuranceStudy (FIS) report and forty-nine FIRM panels along the San Francisco Bay shoreline. On March24, 2014 the Preliminary Flood Insurance Study and the Preliminary Flood Insurance Rate Mapswere received by the City. FEMA has posted digital copies of the revised FIRM panels, FISreport, and Digital FIRM database to the following website:https://hazards.fema.gov/femaportal/prelimdownload/.

FEMA is expected to issue final FIRMs in September 2015 which will show a new base floodelevation of 10 feet NAVD near and around the Hamilton levee area.

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3.2 FEMA Map Actions and Re-AccreditationWhen FEMA issues preliminary DFIRM updates that affect the area around the levee system, re-accreditation of the levee may be required. Levee re-accreditation should be completed prior tothe final issuance of updated FIRMs. The sections below describe the elements of theaccreditation process under 44 CFR Section 65.10.

3.2.1 Design CriteriaFEMA has established Levee Design Criteria which includes freeboard requirements,embankment protection, stability and settlement criteria; and interior drainage. In addition,various operations and maintenance plans are required for a levee to be accredited. Thefollowing section provide more details of these requirements.

3.2.1.1 FreeboardFor coastal levees such as the Hamilton Field levee, the freeboard must be established at onefoot above the height of the one percent wave or the maximum wave runup (whichever isgreater) associated with the 100-year stillwater surge elevation at the site. Under nocircumstances, however, will a freeboard of less than two feet above the 100-year stillwatersurge elevation be accepted.

3.2.1.2 Embankment ProtectionEngineering analyses must be submitted that demonstrate that no appreciable erosion of thelevee embankment can be expected during the base flood, as a result of either currents orwaves, and that anticipated erosion will not result in failure of the levee embankment orfoundation directly or indirectly through reduction of the seepage path and subsequentinstability.

3.2.1.3 Stability AnalysesEngineering analyses that evaluate levee embankment stability must be submitted. Theanalyses provided must evaluate expected seepage during loading conditions associated withthe base flood and must demonstrate that seepage into or through the levee foundation andembankment will not jeopardize embankment or foundation stability. An alternative analysisdemonstrating that the levee is designed and constructed for stability against loadingconditions for Case IV as defined in the U.S. Army Corps of Engineers (USACE) Engineer Manual1110–2–1913, Design and Construction of Levees, (Chapter 6, Section II), may be used.

3.2.1.4 Settlement AnalysesEngineering analyses must be submitted that assess the potential and magnitude of futurelosses of freeboard as a result of levee settlement and demonstrate that freeboard will bemaintained. This analysis must address embankment loads, compressibility of embankmentsoils, compressibility of foundation soils, age of the levee system, and construction compaction

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methods. In addition, detailed settlement analysis using procedures such as those described inUSACE Engineer Manual 1110–1–1904, Soil Mechanics Design— Settlement Analysis, must besubmitted.

3.2.1.5 Interior Drainage AnalysesAn analysis must be submitted that identifies the source(s) of interior flooding (inboard of thelevee), the extent of the flooded area, and, if the average depth is greater than 1 foot, thewater-surface elevation(s) of the base flood. This analysis must be based on the jointprobability of interior and exterior flooding and the capacity of facilities (such as drainage linesand pumps) for evacuating interior floodwaters.

3.2.2 Operations PlanAll closure devices or mechanical systems for internal drainage, whether manual or automatic,must be operated in accordance with an officially adopted operation manual, a copy of whichmust be provided to FEMA by the operator when levee or drainage system recognition is beingsought or when the manual for a previously recognized system is revised in any manner. TheHamilton Field levee system does not include any closure devices or mechanical systems forinternal drainage.

3.2.3 Interior Drainage PlanInterior drainage systems associated with levee systems usually include storage areas, gravityoutlets, pumping stations, or a combination thereof. These drainage systems will be recognizedby FEMA on NFIP maps for flood protection purposes only if the following minimum criteria areincluded in the operation plan.

1. Flood Warning System: Documentation of the flood warning system, under thejurisdiction of Federal, State, or community officials that will be used to triggeremergency operation activities; and demonstration that sufficient flood warning timeexists to permit activation of mechanized portions of the drainage system.

2. Plan of Operation: A formal plan of operation including specific actions and assignmentsof responsibility by individual name or title.

3. Manual Backup: Provision for manual backup for the activation of automatic systems.

4. Periodic Inspection: Provisions for periodic inspection of interior drainage systems andperiodic operation of any mechanized portions for testing and training purposes. Nomore than 1 year shall elapse between either the inspections or the operations.

3.2.4 Adopted Maintenance PlanLevee systems must be maintained in accordance with an officially adopted maintenance plan,and a copy of this plan must be provided to FEMA by the owner of the levee system when

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recognition is being sought or when the plan for a previously recognized system is revised inany manner.

All maintenance activities must be under the jurisdiction of a Federal or State agency, anagency created by Federal or State law, or an agency of a community participating in the NFIPthat must assume ultimate responsibility for maintenance.

This plan must document the formal procedure that ensures that the stability, height, andoverall integrity of the levee and its associated structures and systems are maintained. At aminimum, the plan shall specify the maintenance activities to be performed, the frequency oftheir performance, and the person by name or title responsible for their performance.

This O&M Manual is intended to comply with the above requirement.

3.2.5 CertificationData submitted to support that a given levee system complies with the structural requirementsset forth in “Design Criteria” (Paragraphs 65.10(b)(1) through (7) of the regulations) must becertified by a Registered Professional Engineer. Also, certified “as-built” plans of the levee mustbe submitted. Certifications are subject to the definition given in Section 65.2 of the NFIPregulations.

The Public Works Engineering Division maintains the FEMA Accreditation documents, includingprior submittals to FEMA for approval. A new accreditation submittal is planned for the springof 2015 prior to the final issuance of the final FIRMs.

3.3 Community Rating System (CRS)The City participates in the National Flood Insurance Program’s Community Rating System(CRS). To be covered by a flood insurance policy, a property must be in a community thatparticipates in the NFIP. To qualify for the NFIP, a community adopts and enforces a floodplainmanagement ordinance to regulate development in flood hazard areas. Activity 620 of the CRSprogram covers levees. The objective of this activity is to encourage communities to properlyinspect and maintain levees and to identify impending levee failures in a timely manner,disseminate warnings to appropriate floodplain occupants, and coordinate emergency responseactivities to reduce the threat to life and property. The items credited by this activity include:

Proper maintenance of the levees, A system to advise local emergency managers of a potential levee failure or

overtopping, A warning system for people on the landward side of the levee, A plan of action to minimize the threat to life and property during the flood, and Coordination with critical facility operators

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For levee maintenance credit, a community must implement a levee maintenance plan, createand maintain an inventory of levees, identify the vulnerable population and at-risk structures,and conduct an outreach project to advise the vulnerable population. Levee maintenance is aprerequisite for the four emergency preparedness and response elements covered under theCRS program. This O&M Manual is designed to comply with the CRS requirements.

3.4 Federal Rehabilitation AssistanceThe USACE and the Natural Resources Conservation Service (NRCS) have primary authority forthe repair of flood control works. USACE’s authority is contained in the Flood Control andCoastal Emergency Act, Public Law (PL) 84-99 (33 U.S.C. 701n) and Title 33: Navigation andNavigable Waters, and NRCS’ authority is contained in Section 216 of the Flood Control Act of1950, PL 81-516, and Sections 403-405 of the Agriculture Credit Act of 1978, PL 95-334, asamended by Section 382 of the Federal Agriculture Improvement and Reform Act of 1996, PL104-127.

In 1986, USACE and NRCS signed a Memorandum of Agreement to provide general policyguidance and coordination between the two agencies for the repair of levees and other floodcontrol works. The agencies agreed that, depending on program eligibility, NRCS wouldgenerally be responsible for repairing flood control works in watersheds with contributingdrainage areas less than 400 square miles and USACE would be responsible for repairs toeligible non-federal flood control works in urban areas regardless of watershed size. Theagreement remains in effect.

The USACE Rehabilitation and Inspection Program (RIP) provides for the inspection andrehabilitation of Federal and non-Federal flood control projects. To be eligible for rehabilitationassistance following a disaster, a flood control work must have a public sponsor, be regularlymaintained, and have an Active RIP status prior to the event. USACE can provide flood fightingassistance to applicants during a flood event. However, USACE cannot reimburse applicants fortheir own flood fighting efforts or for the removal of debris from flood control works. AdditionalRIP criteria are available in the USACE manual entitled “Emergency Employment of Army andOther Resources - Civil Emergency Management Program,” ER 500-1-1.

The Stafford Act includes flood control facilities (including levees) as public facilities that areeligible for assistance under the Act. (See 42 U.S.C. 5122.) FEMA provides assistance foremergency protective measures to eliminate immediate threats to life, public health and safety,or improved property. (See 42 U.S.C. 5170b and 5173). Although such measures may includeflood fighting, debris removal, and emergency repairs, the NRCS has specific authority toprovide assistance to protect life and property in watersheds from erosion and flooding, andUSACE has specific authority to provide assistance for flood fighting activities during flooding.

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FEMA will not provide assistance for emergency protective measures under the Stafford Actwhere NRCS or USACE authority is applicable, as these authorities are more specific thanFEMA’s. When other Federal agencies have the specific authority to repair facilities that arealso eligible under the Stafford Act, FEMA defers to the other Federal agencies. This is codifiedin 44 CFR §206.226(a), Assistance under other Federal agency (OFA) programs.

The City has been communicating with the USACE San Francisco District regarding eligibility intothe USACE Rehabilitation Program. It is anticipated that the City will work closely with USACE in2015 to ensure compliance with the Program. The overall content and the procedurescontained in the O&M Manual are designed to comply with USACE requirements.

3.5 Compliance with Environmental and Historic PreservationRequirementsThe City’s Levee System maintenance program strives to stay compliant with applicable federalenvironmental and historic preservation laws and executive orders as required by FEMA.

A completed CC-620EHP form, Certification of Compliance with Environmental and HistoricPreservation Requirements for Levee Maintenance, is provided in Appendix F.

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4.0 LEVEE SYSTEM INSPECTION PROGRAM

4.1 General ProceduresSeveral different types of inspections are performed on the levee system, including routineinspections, detailed annual inspections, elevation surveys, and special inspections. In general,visual inspections and operational checks are performed regularly to ensure proper pumpstation operation and levee performance. More detailed description of specific inspections arepresented below.

4.2 Routine InspectionsThe City’s Maintenance Division performs routine inspections of the levee system. Daily visualchecks are performed to look for signs of vandalism, fuel leaks, debris, storm damage, as well asoverall site security. Weekly or Monthly inspections of the pump stations involves a more in-depth level of evaluations and is discussed in more detail in Section 5.5. Routine inspections forthe levee system are performed on the following areas:

Pump Stationso Main Siteo Outfall Structures

Levee Embankmento Outboard Slopeo Inboard Slopeo Seepage Collection System

Levee Crowno Access Roado Splash Wallo Closureo ADA Access Ramp area

Overall Site Securityo Access gateso Signage

The “Hamilton Field Levee System Periodic or Special Inspections” inspection form should beused to record monthly formal inspections.

A copy of the inspection form is provided in Appendix G.

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4.3 Annual InspectionFor annual inspections, the City utilizes the USACE Flood Damage Reduction Segment/SystemInspection Report (referred to as the Levee Inspection Checklist) developed under the USACERehabilitation Inspection Program and tailored specifically to the Hamilton Field Levee System.The checklist is used monitor the overall levee system condition on an annual basis; identifydeficiencies; verify that needed maintenance is taking place; and provide overall informationabout the levee system to Public Works management. The inspection information alsocontributes to risk assessments and supports levee accreditation decisions under the NFIP.

4.3.1 Inspection RatingsThe Inspections result in a final inspection rating for operation and maintenance. The rating isbased on the levee inspection checklist, which includes 125 specific items dealing withoperation and maintenance of levee embankments, floodwalls, interior drainage, pumpstations, and channels.

Each levee segment receives an overall segment inspection rating of Acceptable, MinimallyAcceptable, or Unacceptable. The City, as a potential “levee sponsor” (in USACE parlance) mustmaintain the levee to at least the minimally acceptable standard to remain eligible for federalrehabilitation assistance through the USACE Rehabilitation and Inspection Program (PL 84-99).A description of the inspection ratings is provided below.

Levee System Inspection RatingAcceptable All inspection items are rated as Acceptable – no deficiencies noted.MinimallyAcceptable

One or more inspection items are rated as Minimally Acceptable or oneor more items are rated as Unacceptable and an engineeringdetermination concludes that the Unacceptable inspection itemswould not prevent the segment/system from performing as intendedduring the next flood event.

Unacceptable One or more inspection items are rated as Unacceptable and wouldprevent the segment/system from performing as intended, or a seriousdeficiency noted in past inspections (previous Unacceptable items in aMinimally Acceptable overall rating) has not been corrected within theestablished timeframe, not to exceed two years.

The Hamilton Levee Inspection Checklist, used for yearly inspections, is provided in Appendix H.

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4.4 Elevation SurveysElevation surveys are performed to measure and record the height of the levee crown(centerline), the height of the splash wall, and the height of monitoring monuments located onthe outboard side of the wall. A total of 32 survey monitoring locations have been establishedalong the levee where the splash wall is present. The locations are marked with a placard orstencil beginning with “SM-1” at approximately Station 64+10 at the northern extent of thesplash wall to “SM-32” at the southern end of the wall near Pump Station #1. The actualmonuments consist of 3/8-inch thick steel plates imbedded in the CMU wall that protrude fromwall approximately 1/2-inch. The tabs should be periodically spray painted to help identify theirlocation.

In addition to the 32 wall monument locations, an additional monument, designated as SM-33,is located in the paved access road near Pump Station No. 1. This monument is a standard citymonument used at other locations within the city. In addition to the marked monumentlocations, crest elevation locations have been established every 100 feet at the northern extentof the levee embankment, north of the splash wall terminus. These survey locations begin atStation 65+00 and end at Station 71+00.

Elevation surveys shall be performed at least every 2 to 3 years by a licensed surveyor orlicensed civil engineer. Elevations should be taken at each of the 33 monitoring locations,including the levee crest, the top of the splash wall, and at the monument location. Additionallevee crest elevations shall be performed from Station 65+00 to 71+00. The EngineeringDivision is responsible for coordinating the elevation surveys.

The results of the 2014 survey are presented below:

MonitoringLocation (SM-X)

LeveeStation

Levee CrestElevation

MonumentElevation

Top of SplashWall Elevation

1 64+10 13.6 12.45 15.252 62+11 12 10.57 15.323 60+11 11.7 9.32 14.74 58+11 11.8 9.67 15.135 56+16 12 10.2 14.976 54+16 11.8 10.21 14.997 52+13 12.1 10.57 14.738 50+13 11.8 9.78 14.559 48+13 11.7 9.86 14.63

10 46+13 11.93 9.89 14.5911 44+20 11.57 10.4 15.1712 42+20 11.6 9.72 14.4813 40+20 11.6 9.69 14.46

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MonitoringLocation (SM-X)

LeveeStation

Levee CrestElevation

MonumentElevation

Top of SplashWall Elevation

14 38+20 11.7 10.21 14.9715 36+21 11.8 10.21 15.0116 34+20 12 10.27 15.0417 32+20 12.2 10.24 15.0218 30+21 12.5 10.5 14.6319 28+20 11.5 11.18 14.6620 26+19 11.9 10.02 14.8121 24+19 11.7 10.05 14.8322 22+19 12 10.36 15.1123 20+23 11.7 10.09 14.8824 18+23 11.7 10.19 14.9725 16+24 11.6 9.79 14.5826 14+51 11.5 9.45 14.8627 12+53 11.5 9.8 14.5928 10+53 11.9 10.86 14.9929 8+56 12.1 11.69 15.1430 6+56 11.9 10.26 15.0631 4+58 11.7 10.34 15.0832 2+78 11.3 10.95 15.7133 2+00 Not surveyed

- 65+00 13.55- 66+00 14.00- 67+00 13.48- 68+00 13.41- 69+00 13.70- 70+00 13.38- 71+00 12.72

Averages 12.14 10.27 14.90Table Note: Elevations shown are in NAVD88. Survey performed in July 2014 by Prescott & White withsupplemental data obtained by the Public Works Department.

The elevation survey form shall be used to document the survey elevations. A copy of the formis provided in Appendix I.

4.4.1 Seal Level RiseSea Level Rise (SLR) may ultimately have an impact on the levee system and its ability toprovide flood protection. Based on the 2014 elevation survey data, the levee embankmentprovides approximately 2 feet of freeboard above the proposed 2015 100-year flood elevation;and the splash wall provides approximately 5 feet of freeboard (based on average elevations for

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the levee crest and splash wall, respectively). California’s Sea-Level Rise Guidance Documentrecommends using a range of 2 to 12-inches of sea level rise increase by 2030 and 5 to 24-inchincrease by 2050. These recommendations are based on the scientific findings of the NationalResearch Council (NRC) Sea-Level Rise for the Coasts of California, Oregon, and Washington(2012).

Compounding the effects of SLR is the future potential of levee settlement. Using settlementtrends development under previous studies (URS/ARUP 2006), the range of future settlementby 2057 is 3 to 8 inches (Geosyntec 2014). It is likely that regardless of the predictions, SLR willeffect FEMA’s future determinations of base flood elevations, effectively raising them overtime. The function and designation of the splash wall will likely evolve into a true flood wallover the next 50 years.

4.5 Special InspectionsSpecial inspections are warranted when unordinary or unusual events require visualobservations or inspections of the levee system. Example events include large storm events;extreme high tides (known as king tides) coupled with storm events; when evidence of seepageis observed or reported; or the occurrence of a local or regional earthquake or similar disaster.See Section 7 for more information related to storm events and natural disasters.

4.5.1 Localized SeepageLocalized seepage is defined as evidence of isolated seepage effecting individual residences orproperties along the levee embankment. This type of seepage is difficult to observe andmonitor during routine levee inspections and therefore may require input or notification by theimpacted residents. Typically this type of seepage manifests itself at the properties locatedalong the inboard toe of the levee. The Public Works Department will respond to homeownernotification or complaints and perform the following level of investigations:

Interview the property owner or person familiar with the recent history of the property Visual inspect the property, including adjoining properties if accessible Take photographs of the area in question Inspect and ensure the function of toe drains/collection system in the area Request that the property owner(s) inspect area drains and irrigation systems to ensure

proper function (this may require outside forces) Review as-built data for the development If warranted, video the nearby storm drainage to determine condition of the system Perform follow-up visual inspections within 1 – 3 weeks

Localized seepage investigations should involve representatives from the Engineering andMaintenance Divisions. Depending on the results of the actions described above, further

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investigations may be required such as installation of monitoring wells/piezometers. Regardlessof the results of the initial investigation, provide follow up reporting to the EngineeringManager and Public Works Director, and possibly the Public Communication Coordinator.

4.5.2 Pre and Post Storm EventsPrior to a predicted or forecasted significant storm event with either associated high winds orlarge amounts of precipitation, the levee system should be inspected. If extreme high tides(greater than 7.5 feet) are predicted concurrent with a large storm event, the wall closure gateshould be closed. When safe to do so, an inspection should be performed after a storm eventhas passed.

The “Hamilton Field Levee System Periodic or Special Inspections” inspection form should beused for both the pre and post storm event inspections.

4.5.3 Post Disaster EventsThe City of Novato is located near two active earthquake faults: The North San Andreas Fault tothe west, and the Rodger’s Creek Fault to the east. Other active faults, such as the HaywardFault are located to the east of the city. In addition, an inactive historic fault, the BurdellMountain Fault, is partially mapped within the city limits. The probability of a major earthquake(a magnitude 6.7 or greater) before 2032 has been calculated for the two active faults asfollows:

N. San Andreas Fault – 21% Rodger’s Creek Fault – 27%

The levee embankment has been evaluated for seismic stability (Geosyntec 2014) in accordancewith FEMA standards. Displacement analysis was done for the levee embankment forearthquakes occurring on the San Andreas Fault (magnitude 8.0) and the Hayward Fault(magnitude 7.0). Based on that analysis it is estimated that the levee embankment coulddisplace as much as 13 inches in the horizontal direction. This is well below the criteriaestablished by the state (DWR, 2012) of 3 feet. However, ground shaking from an earthquakeevent may cause unwanted distress or damage to the levee system. Therefore, a leveeinspection should be performed following an earthquake or in the less likely event of a tsunami.

The “Hamilton Field Levee System Periodic or Special Inspections” inspection form should beused for post disaster event inspections.

For detailed information regarding pre and post storm and post disaster event procedures seeSection 7.

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5.0 INTERIOR DRAINAGE PLAN

5.1 OverviewThe Hamilton Field Levee interior drainage system consists of a storm drainage collection andconveyance network and two storm water pump stations. The storm drainage collection systemconsists primarily of roadway inlets and associated manholes and piping. Other drainagecollection consists of concrete v-ditches within the surrounding hillslopes and at portions of theinboard (land side) toe of the levee. The majority of the single family homes within the variousHamilton subdivisions have yard drains (typically 4-inch diameter or smaller) that collect runofffrom roof downspouts as well as area drains that are connected to the storm drainage system.Similarly, the commercial development within the area have similar drainage systems. Aconcrete v-ditch is present along the majority of the levee embankment. The v-ditch is designedto collect surface run-off from the embankment. The v-ditch is connected to the city’s stormdrainage network by a series of catch basins and associated pipes at various points along theditch alignment.

In general the northern portion of the Hamilton development, north of the intersection of PalmDrive and Hangar Avenue, is served by the Bayside Pump Station #2; and the central, western,and southern portions of the site are served by Pump Station #1 as shown in the followingfigures.

Interior drainage areas are presented on the following pages

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Interior Drainage Area Generally Served by Pump Station #2

BAYSIDE PUMP STATION #2

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Interior Drainage Area Generally Served by Pump Station #1

5.2 Pump StationsThe pump stations are designated as the Hamilton Pump Station No. 1 (or simply Pump Station#1, P.S. #1); and Bayside Pump Station No. 2 (or simply Pump Station #2, P.S. #2). As-builtrecord drawings for each pump station is provided in Appendix B. More detailed informationfor each station is provided in the next subsections.

Each pump station has detailed O&M Manuals that describe equipment operation,maintenance and repair, specifications, and other information. Complete sets of the manualsare stored at each pump station and copies are kept at the city’s Corporation Yard. The O&MManual for Pump Station #1 is an eight volume set of binders; the manuals for Pump Station #2is also a multiple volume set.

SEPARATE DRAINAGE

PUMP STATION #1

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5.2.1 Hamilton Pump Station #1The Hamilton Pump Station (P.S. #1) was constructed in 1997 as part of the first phase of theHamilton Field redevelopment. The pump station is located at the southern terminus of HangarAvenue and the southern extent of the levee (Sta. 0+00). The pump station consists of a motorcontrol center shed, a service shed, below ground wet well/pump area, above ground dieselpumps, and discharge/outfall and trash track. Pumping capability consists of the following:

Two 120hp electric submersible pumps Three 355hp right-angle drive diesel engine pumps One 3hp electric sump pump

There are a total of five discharge pipes that terminate at the outfall/trash rack structure southof the levee embankment. There are three 48-inch and two 24-inch welded steel pipesdischarge lines Each discharge line has a flap gate that is normally closed when no flow ispresent to prevent backflow of tidal water (at high tides). The pump station, excluding theoutfall structure is enclosed by a screened chain-link fence topped with barbed wire. Accessthrough the fence is provide by a double vehicle swing gate. The gate is normally locked at alltimes except when an operator is present.

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View from inside P.S. #1 fencing showing top of wet well

5.2.2 Bayside Pump Station #2The Bayside Pump Station (P.S. #2) was constructed in 1999 as part of the second phase of theHamilton Field redevelopment. The pump station is located at 134 Pizzaro Avenue near thenorthern limit of the levee. Unlike P.S. #1, the pumps at P.S. #2 are vertical shaft pumps and arehoused inside a small building. A second small building houses a standby emergency generatorfor the station. The site is bordered by residential parcels developed with single family homes.The design and finishes for the two building match the overall architectural style of thesurrounding homes. A wooden fence is present around the entire perimeter of the pumpstation parcel. Access is via a wooden entrance gate and driveway entrance off Pizzaro Avenue.The pump station parcel borders the levee embankment and access to the levee is availablethrough another wooden gate behind the pump building.

Pumping capability at P.S. #2 consists of the following:

Three 60hp electric vertical shaft pumps One 3hp electric sump pump One 1/2hp electric cooling water pump (for generator)

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There are a total of three 20-inch welded steel pipe (WSP) discharge lines, one for each 60hppump; and one 4-inch WSP discharge line for the sump pump. The 20-inch discharge lines haveflap gates and the sump discharge has a check valve to prevent backflow of tide waters.

View of P.S. #2 at entrance gate showing pump building (left) and generator building (right)

5.2.3 Supervisory Control and Data Acquisition (SCADA)The two pump stations are linked via radio telemetry to a limited SCADA system at the City’sCorporation Yard at 550 Davidson Street. The radio communication system is setup as a “Point-to-Multi-Point” via a “Bridge” network using line of sight radio antennas. The radio access pointis the main radio unit and associated SCADA PC workstation in the Maintenance Building at theCorporation Yard (Corp Yard). The line of sight antenna at the Corp Yard communicates with theantenna at the Bayside Pump Station which “bridges” the communication to the HamiltonPump Station. The SCADA interface software (Wonderware InTouch) allows for pump operationat each station as well as operational status and condition information at each wet well bycommunication with each station’s respective PLC (Programmable Logic Controller). The SCADAsystem also provide alarm notification including dial out to multiple phone numbers.

As part of the daily pump station operations, a duty phone is assigned to the primary PublicWorks staff member. The dedicated “pump station operation” cellular phone is (415) 858-9300.

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Radio Communication Line-of-Sight Overview

Radio antenna at Pump Station #2.

Corp Yard

P.S. #2

P.S. #1

Radio Link

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The SCADA system allows for remote operation of pump operation including level controlsetpoints. Several graphical screen displays have been developed to provide a user-friendlyimage of the actual pump station layout. Daily operation procedures should include physicalobservation at each pump station as well as the SCADA interface.

The SCADA system is capable of displaying alarm status including the following:

Wet well water level Power failure Ultrasonic water level detector failure Pump failure Fuel tank level/leak

The SCADA system can dial out the alarms to the duty phone and key members on the dutyroster.

5.3 Storm Drainage NetworkAs described in the beginning of this Section, storm water runoff is collected via roadway curbinlets and catch basins, area drains, and concrete v-ditches. In general, there no open ponds,

Screen shot of SCADA – showing Pump Station #1 diesel pump status

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catchments, flood channels within the Hamilton area. However, a short segment of earthenditch is present along the north side of Palm Drive, east of Main Gate Road. Storm drain pipeswithin Hamilton range in size from 12 inches to 84 inches. Smaller area drains and collectorpipes range in size from 4-inch to 10-inch. Pipe materials include poly vinyl chloride (PVC)plastic; high density polyethylene (HDPE) plastic; and reinforced concrete pipe (RCP).

Storm drain structures such as catch basins, drop inlets, and v-ditches generally conform to theMarin County Uniform Construction Standards (UCS). Area drains are commercially availablepre-molded plastic inlet/catch basins with grated inlet covers. Special pipe trench backfillingdetails were used throughout the area to address settlement and shallow groundwaterconditions.

The majority of the subdivision development in the central and southern portions have yardarea drains that collect surface runoff from individual properties. In most cases the individualdrains connect 8 to 10-inch diameter PVC collector pipes along the back of sidewalk. Thecollector pipes then connect to the storm drain system within the adjoining street.

Pump Station #1 has an 84-inch RCP storm drain inlet at the wet well. This main inlet pipeconnects to other trunk lines along Hangar Avenue and the other surface streets. The stormdrain trunk lines range from 15-inch to 72-inch diameter pipe. Pump Station #2 has a 60-inchRCP inlet at the wet well.

5.4 Interior Drainage AnalysisAs required by FEMA’s levee accreditation process, an analysis of the interior drainage isrequired that identifies the source(s) of interior flooding inboard of the levee, including theextent of the flooded area, and, if the average depth is greater than 1 foot, the water-surfaceelevation(s) of the base flood. This analysis must be based on the joint probability of interiorand exterior flooding and the capacity of the existing storm drainage system facilities forevacuating interior floodwaters.

The pump stations were designed for 100-year storm runoff flows form their respectivecontributory sub-watersheds within the Hamilton area (CSW/Stuber-Stroeh 1993 and 1997).This original design used the rational method of hydraulic analysis and rainfall data fromCaltrans Rainfall Intensity-Duration-Frequency (IDF) curves. In 2015, as part of the City’s StormDrainage Master Plan updates, a hydrologic and hydraulic model was created for the City’sstorm drainage system, including the Hamilton Area protected by the levee. Several stormevent scenarios were evaluated using the model to determine the extent, if any, of interiorflooding.

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5.5 Pump Station InspectionsSeveral different types of inspections and inspection frequencies are required for the pumpstations. Daily, weekly, monthly, and annual inspection requirements are presented below.

5.5.1 Daily ChecksDaily checks or visual inspections are performed to evaluate general conditions and operationof the pump stations. Daily checks are basic and intuitive to the operator and consist of thefollowing items:

Lighting Signs of vandalism Fuel or oil leaks Locking devices Wet wells Outfall/trash racks

Daily checks don’t require documentation unless a deficiency or problem is detected and afollow up action is required.

5.5.2 Monthly InspectionsMonthly inspections are more involved than daily checks and cover all components of thepump stations. The monthly inspections cover the following areas:

Structure:Clean all debris from structure and trash racks.Check mounting of trash rack and catwalk, and adjust as necessary.Check all ladders for structural defects and mounting, and repair as required.General overall inspection of structure for signs of damage and/or replacement.Check grating and handrails for structural defects and mounting and repair as necessary.Check site/driveway for any drainage problems and clear or repair as necessary.Check all yard and structure lights.

Motor Control Center(s)Check anchors for control building and tighten as necessaryCheck/clean ventilation screensClean inside of buildingResistance testing for power cables/motorsCheck all connectionsCheck batteries for UPS and DialerCheck calibration of ultrasonic level controllerCheck float switch operation

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Engine (P.S. 1):Take oil sampleChange oil and oil filtersChange oil fuel filtersAdjust valvesAdjust injectorsCheck timing and setClean crankcase breather

Fuel System:Inspect all fuel system components for evidence of sludge or rust.Check fuel quality and perform fuel polishing and/or replacement.

Intake System:Check all intake system hoses and connections (tighten).Clean and refill air cleaners.

Governor (P.S. 1):Check all linkage and ball jointsCheck any unusual oil, fuel leakageCheck electronic governor settings (adjust if necessary)

Cooling System:Check coolant level and inhibitor content.Change water filter.Check filler neck.Check exterior of radiator.Check engine water pump and lube as necessary.Check fan drive assemblies and lube as necessary.Check duct work for looseness (tighten).Clean air discharge if required.Check jacket water heater for correct operation.Check hoses and connections (tighten if loose).Change coolant.

Exhaust System:Visually check condition of muffler, exhaust lines, supports, and connections (tighten if loose).Open condensation drains.

Engine Electrical Starting System:Check battery electrolyte specific gravity.Check battery cap vents.Check battery charger.Clean and check battery and connections.

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Check for proper RPM.Check for correct operation of starter disconnect.

Engine Controls:General cleaning.Check appearance of air components.Check instruments for normal function.Check operation of all engine operating alarms and safety shutdown devices.

Engines/General:Visually check engine mounts (tighten if loose).Visually check complete unit.

Right Angle Gear Drive (P.S. 1):Change oilCheck all connections and tighten as necessaryCheck water supply

Emergency Generator, General (P.S. 2):General Condition of EnclosureAnchor Bolts properly securedInspect for leaks (engine)Check belts & hosesCheck wiring for loose connectionsCheck for loose clampsCheck oil levelOil Drain Line & ValveCheck Fuel LineFuel Tank Fill NozzleFuel Filter AccessBattery InstallationCheck cooling fan connectionsInspect for leaks (cooling water)Exhaust Silencer connectionExhaust Silencer properly mountedExhaust piping vent outlet screen

48" Diesel Pumps (3):Change oil (lubrication system).Check solenoid valve operation.Check impeller, adjust as necessary.

120 HP Electrical Submersibles (2):Remove pump and inspect casing, impeller, cables, bolts and nuts.

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Perform "leak check" on mechanical seal (upper).Change oil in mechanical seal (lower).Check rail system.

60HP Electrical Vertical Pumps (3):Remove pump and inspect casing, impeller, cables, bolts and nuts.Perform "leak check" on mechanical seal (upper).Change oil in mechanical seal (lower).

3 HP Electric Sump (one at each P.S.):Remove and replace motor and seal insulating oil.Inspect cables.Inspect impeller, casing.Check bolts/nuts.Check cage.Check rail system.

Outlet/Outfall Works (one at each P.S.):Check bolts for tightness.Check operation of flap gates and check valve.Check for trapped debris on trash racks

Photo of Outlet/Outfall Works at P.S. 1

Pump Station inspection forms have been developed and are provided in Appendix J.

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5.5.3 Annual InspectionsFor annual inspections of the levee system, the City utilizes the USACE Levee InspectionChecklist tailored specifically to the Hamilton Field Levee System, including the two pumpstations. The checklist is used monitor the overall pump station condition, including thefollowing areas:

Overall Operations and Maintenance Safety Compliance Communications Buildings Perimeter fencing and gates Pumps Motors, engines, fans Wet wells Fuel Systems Power Sources Electrical Systems Intake and Discharge Pipelines Outfall Structures Platforms, ladders, metallic components

In addition to completing the Levee Inspection Checklist, the following special annualmaintenance activities and tests shall be performed:

Wet well cleaning and inspection Megohmmeter testing (megger testing) of pump motors and critical cables

Annual inspections provide an ideal time to review O&M data and make revisions/updates asnecessary.

5.6 Pump Station MaintenanceThe daily, monthly and annual inspections can identify the need for maintenance or repair ofthe pump station components. As described in Section 5.2, each pump station has detailedO&M Manuals that describe equipment operation, maintenance and repair, specifications, andother information. Complete sets of the manuals are stored at each pump station and copiesare kept at the Corporation Yard. Specific maintenance procedures for the equipment iscontained in the manuals.

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5.7 Storm Drainage InspectionThe Hamilton storm drainage system is inspected and maintained in accordance with the City’sDrainage System Maintenance Standard Operating Procedures (July 2014 update). Each year, adedicated crew from the Streets Division performs inspections and cleaning of the storm drainnetwork. As described in Section 5.5.3, annual cleaning inspection of the pump station wetwells as well as the inlet piping is performed.

5.8 Flood Warning SystemThe City has developed a Hazard Detection and Warning Program that addresses variousthreats and events that impact the community as a whole or specific neighborhoods or localareas. The Program includes procedures and tools available to City personnel to detect a threatas well as to warn the public of threat events. Because of the unique infrastructure within andadjacent to the City, the cause of flooding within the Hamilton Area can be from the followingsources: 1) Storm drain system capacity exceedance (storm events); 2) Levee failure andinundation (caused earthquake); or 3) Levee overtopping (storm events combined with extremehigh tide).

The Traffic Section of the Public Works Maintenance Division is responsible for day-to-dayoperations and maintenance, as well emergency operations of the Hamilton Field LeveeSystem. Since tidal conditions are an integral part of the impacts of winter storms on the leveearea, monitoring of predicted tidal levels as well as the observed tide stage is an importantcomponent of the levee system emergency response. In general, local tides in the Novato areaoccur approximately an hour later than tides at the San Francisco Bay inlet (Golden Gate Bridge)and can be +/- 0.1 feet difference in height. Note that tide water levels are typically publishedrelative to the Mean Lower Low Water (MLLW) datum. The conversion to North AmericanVertical Datum 1988 (NAVD88) is as follows:

0 feet NAVD88 = -0.187 feet MLLW.

Several resources are available to monitor weather and tidal conditions including a weatherstation recently acquired (2014) by the Novato Fire District. Weather data from this station isavailable at:

http://raws.wrh.noaa.gov/cgi-bin/roman/meso_base.cgi?stn=NBRC1&time=GMT

The City staff also monitors weather forecast information from the NWS directly via theirwebsite:

http://forecast.weather.gov/MapClick.php?CityName=Novato&state=CA&site=MTR&textField1=38.1075&textField2=-122.569&e=0#.VEAohWd0zDA

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An Automated Local Evaluation in Real-Time (ALERT), is available to City staff via the MarinCounty Flood Control and Water Conservation District (MCFCWCD). The system serves has alocal flood warning system the Novato Creek watershed as well as other areas in Marin County.Real time data is available via the County’s website:

https://marin.onerain.com/site.php?site_id=1552&view_id=3

Tide predictions are available here (Point Pinole – southeast of the Novato shoreline):

http://tidesandcurrents.noaa.gov/noaatidepredictions/NOAATidesFacade.jsp?Stationid=9415056

Current tide water levels are available here (Point Pinole Station):

http://tidesandcurrents.noaa.gov/stationhome.html?id=9415056

Tide water levels are alternatively available here (Point Richmond):

http://tidesandcurrents.noaa.gov/stationhome.html?id=9414863

Tide water levels adjusted for the mouth of Novato Creek at San Pablo Bay are available here:

http://tides.willyweather.com/ca/marin-county/san-pablo-bay--novato-creek-entrance.html

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6.0 LEVEE SYSTEM MAINTENANCE PLAN

6.1 Vegetation ManagementConsistent grass cover is one of the most effective and economical means of protecting thelevee embankment against erosion caused by rain runoff and trespassers. The grass coverrequires periodic mowing and possible spot repairs/re-seeding as needed. In addition, everyeffort must be made to prevent unauthorized encroachments, dumping of yard waste, themisuse of chemicals, or pedestrian/pet traffic. Failure to properly maintain the grass cover canresult in unnecessary erosion and possible embankment failure.

Vegetation management areas include the side slopes of the levee embankment and thenarrow transition zone landward of the levee toe. Periodic mowing should be performed tomaintain a good ground cover of grasses and in order to control weeds and to prevent thegrowth of brush and saplings. Long grasses (greater than 12 inches in length) can make a visualinspection nearly impossible and can hide serious concerns such as rodent activity, levee slides,and cracking; all of which can lead to the failure of the levee.

The grass on the levee embankment should be mowed to a minimum height of 3 inches. Thelast mowing of the season should be accomplished under conditions that will allow the grass togrow to approximately 6 to 8 inches by the winter season. It’s important to ensure that theentire levee profile has been mowed, including zones extending to private property lines(fences in most cases).

In accordance with previous agreements, the city is not responsible for maintenance of the SFBay Trail including the trail itself, wetland boundary fencing, and the vegetated area along thetrail (at the base of the CMU wall). The State Coastal Conservancy is currently responsible forthe trail maintenance (through support from other agencies, currently Marin County Parks andOpen Space) until the management of the trail and the adjoining wetlands becomes theresponsibility of another agency (likely the US Fish & Wildlife Service). However, vegetationmanagement of the water side of the northern portion of the levee (Station 65+00 to Station72+16) is performed by the city.

6.2 Animal ControlBurrows created by gophers, ground squirrels, and other animals can lead to levee failuresduring floods. For this reason, an active animal abatement program needs to be implementedto remove these animals. Rodent control techniques may involve fumigation, bait stations, baitbroadcasting, or trapping. Rodent control must comply with the City’s Integrated PestManagement (IPM) program. The city primarily relies on trapping as an abatement control.

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Periodic inspections should detect the presence of burrowing animal activity and are generallymost effective immediately after the levee has been mowed. Significant animal burrows thatare identified should be thoroughly excavated and inspected, backfilled with compacted soilthat is similar to material of the levee, and reseeded. This will avoid the possibility of waterpiping through unfilled portions of the burrows during a flood.

6.3 Levee Drainage DitchesThe levee toe concrete v-ditches should be maintained to ensure that the capacity of the ditchis not decreased by the accumulation of leaves, debris or sediments. The ditches should be

cleared at scheduledintervals and checked forcracks or separation at theconcrete joints. Leave anddebris material removedfrom drainage ditchesshould be removed fromthe area, and not left inarea near the levee slope.Because the majority of thev-ditches border theadjacent private property asshown in the photo, it iscritical to educate propertyowners about the dumping

of yard waste and other debris behind their property. See Section 10.1 for private propertyowner responsibilities.

6.4 Levee Toe DrainsToe drains were not installed as part of the original levee construction. However, as descried inSection 2.1.2, seepage collection structures and toe drains were installed from 2009 to 2011.The toe drains cleanouts should be checked on an annual basis to ensure no blockage. Thedrain lines should be videotaped periodically to ensure proper function. Where toe drainsconnect to inlet structures (such as at 190 Emerson Ave), the connection point and inlet interiorshould checked and flow conditions noted.

6.5 Levee Crown MaintenanceThe design of the levee crown and access road consisted of a 6-inch layer of aggregate basewith a 1% cross slope (sloping away from the splash wall). Ruts and other depressions oftendevelop along the access road as a result of pedestrian or vehicular traffic, settlement, or

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because of an inadequate crown slope. Ruts and depressions are a problem because they allowwater to pond on the levee crown/access road. If left uncorrected, the ponded water will seepinto the levee’s interior or into roadway embankment, saturating the foundation material, andmaking the levee more susceptible to failure during a flood. As part of the levee inspectionprocedures, the levee crown/access road is inspected for ruts, pot holes, and areas of standingwater after it rains.

To correct ruts or depressions, the existing levee surface should be roughened, and looseaggregate base material should be added evenly. Add water or dry the backfill materials asnecessary to attain optimal moisture content during compaction. Compact in place by hand ormechanical methods in order to bring the levee crown back to its original shape.

6.6 Splash Wall Maintenance and RepairMaintenance and repair of the splash wall includes the following components: wall panel joints;wall caps; wall panels; survey monitoring monuments and placards; and graffiti removal. Visiblecracking, scaling, or spalling of the CMU blocks or separation at the panel joints are signs ofmovement and stresses within the wall. The wall panel joints need to be water tight and ofgood integrity.

The water side of the wall has more wall height exposed than the land side and is retaining aportion of the embankment fill due to the levee raising project (See Section 2.1.1). Over time,the exposed concrete masonry surface of the wall will weather, and the lower portions of thewall on the water side may develop efflorescence as moisture passes through and onto thesurface. Efflorescence is caused by salts transported to the surface of the CMU from thepassage of excess moisture. As the water evaporates, it leaves the salt behind, which forms awhite, fluffy deposit. When this occurs applying a protective coating to the wall surface willprolong its life expectancy. Prior to the application of a masonry sealer the structure should becleaned, existing cracks should be sealed with a flexible sealant, and any spalling repaired. Anysealer chosen for the concrete floodwall should be a water or solvent-based acrylic protectivecoating, which may be either clear or colored, and may be textured.

The splash wall may show signs of differential settlement or displacement due to overall leveesettlement, unusual isolated soil conditions, or construction practices (both originalconstruction and subsequent raising). Settlement or displacement will likely occur on anindividual wall panel since each panel was designed and constructed as independent units. As awall panel settles it may begin tilting in the lateral or transverse directions, or settle vertically,resulting in an opening of the wall joint. Historically, this has not been a problem for the splashwall. However, there is one wall panel (near Station 47+00) currently exhibiting lateraldisplacement landward. Monitoring and recording of the joint gap should be performed on amonthly basis (see the inspection checklist).

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6.7 Levee Banks and RevetmentIn general, the levee embankment has not historically shown signs of distress or problems sincethe original construction and subsequent raising. It’s important to closely monitor and evaluateall visible areas for signs of cracking, sloughing or excessive erosion on the levee slopes.Shrinkage cracks are generally narrow and shallow, not extending more than more than a fewinches into the levee embankment, but during long periods of dry weather (or drought) theymay extend as much as several feet into the levee. These cracks can run longitudinally ortransverse to the levee, or may appear as blocks. If the cracking becomes excessive, it needs tobe corrected even if the levee appears to be stable. Crack repair methods should becoordinated with the Engineering Division.

6.7.1 SeepageSeepage problems may or may not be identified during routine inspections and the severity ofthe problems can changed based high tide water conditions. However, if continuously saturatedsoils (not caused by ponded water or poor drainage) are observed on the landward side of thelevee under any condition, they will likely become serious problems under high tide water orstorm conditions. Seepage identification and mitigation should be coordinated with theEngineering Division.

6.7.2 Embankment ProtectionThe northern portion of the levee embankment, from approximately Station 65+75 to Station72+00 has exposed rip rap revetment protecting the levee from wave action. The SF Bay Trailcovers the existing rip rap for the remaining majority of the levee.

For riprap protection to beeffective, it’s important toensure that it is properlymaintained. During projectinspections, look for settledareas that may indicate theriprap is being underminedby wave action, or debris.When undermining or rockdisplacement occurs,additional rock will need tobe added to restore theeven slope. When the rockprotection is uneven thewater flow turbulence will

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increase, resulting in additional erosion of the project or of areas upstream or downstream ofthe project. The protected area needs to be kept free of unwanted brush, saplings, and trees.Unwanted vegetation should be sprayed with an appropriate herbicide to kill the plant, and theroot system should be removed.

6.8 Levee Wall ClosureAs described in 2.1.3.1, there is a single swing gate that was installed in the splash wall to allowADA access to the new SF Bay Trail on the waterside of the levee embankment. The gate

closure is located atapproximately Station 45+60and is designed to provide fullclosure and protection fromflooding. The gate is normallylocked in the open position. Ingeneral the gate requires verylittle maintenance. The springlatch (shown in figure) shouldbe checked periodically andlubricated as necessary.

The rubber gaskets that sealthree edges of the gate shouldbe inspected periodically forsigns of deterioration, crackingor loss of flexibility.

Appendix K contains shop drawings and manufacturer information for the closure gate.

6.9 Storm Drainage MaintenanceThe Hamilton storm drainage system is inspected and maintained in accordance with the City’sDrainage System Maintenance Standard Operating Procedures (July 2014 update). Each year, adedicated crew from the Streets Division performs inspections and cleaning of the storm drainnetwork. Removal of debris, leaves, and sediment from catch basins and inlets is performedprior to the wet seasons. Videotaping of critical lines or lines suspected to have issues shouldalso be performed as necessary. The condition of drainage structures, including the catchmentarea, grates and inlets should be visually inspected and deficiencies noted.

LATCH

GASKET

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7.0 EMERGENCY PROCEDURES

7.1 Purpose and OrganizationThe response activities described in this section have been broken up into two phases: Phase Iare Preliminary Response Activities; and Phase II are Post Event Activities. Phase I activitiesshould be completed before a major storm event. For other emergencies such as anearthquake, Phase I activities can’t take place because the lack of advanced warning. Phase IIactivities include the items that should take place once the storm or disaster event has passed.

This Section is not intended to replace the procedures and requirements in the city’sEmergency Operations Plan (EOP). The EOP is available at the city’s website:

http://www.novato.org/Index.aspx?page=383

7.2 Preliminary Response ActivitiesBy the time a storm event is eminent, everything should be ready, and all necessary personnelshould be prepared to respond to the event. The “Hamilton Field Levee System Periodic orSpecial Inspections” inspection form should be used to inspect the levee system prior to amajor storm event to ensure the levee system is properly prepared for such an event. Inaddition, depending on the nature of the predicted event and the occurrence and timing ofprior to events, the following items should be considered:

General items

Note tide levels and predictions (see Section 5.8) Inspect fences on the waterside of the levee frequently to make sure they are free from

debris. If debris does collect along the fence, it must be cleared immediately or thefence must be cut to free the debris and decrease the possibility of damage to the levee.

Verify that all necessary access roads and ramps along the levee are usable or will besatisfactorily conditioned.

Take photographs of all significant issues. (Use date/time stamp on your camera whenpossible)

Levee Embankment

Look for seeps or unusual wet areas landward of the landside toe. Look for slides or soughs in levee side slopes. Look for wave wash or scouring of the riverside levee slope. Look for low areas in levee crown.

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Text Box

lmcdowall

Text Box


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Monitor toe drains (flowing/non-flowing). Check flap gates for proper closure.

Splash wall

Look for saturated areas or seeps landward of the floodwall. Look for settlement (movement) of the floodwall. Look for bank caving which may affect the structural stability of the floodwall. Inspect the landside of floodwall for any leakage, especially around the joints. Inspect for wet areas, soft areas, seeps, and sink holes landward of the toe of the

floodwall. Check gaps in wall closure.

Pump Stations

Verify proper ventilation (fans on, vents open, etc.) of the pumping building/wet well, toprevent overheating of pump motors.

Look for sink holes or wet areas around the perimeter of the site, and/or settlement ofthe pump house, all of which could potentially be the result of separation in theconduits. If this condition is suspected, the pumps and motors should be shut downuntil an engineering review can be conducted to analyze the condition.

Verify that assigned operators are on duty 24 hours daily.

7.3 Post Event RecoveryPost event activities should begin with another visual inspection of the levee system onceemergency operations have ceased and post recovery is in effect. Again the “Hamilton FieldLevee System Periodic or Special Inspections” inspection form should be used to inspect thelevee system. The additional items described in Section 7.2 should be considered as well.Depending on the nature of the event, post event activities may involve members of theEngineering Division or the Police or Fire Departments.

7.5 Emergency Preparedness and TrainingThe U.S. Department of Homeland Security (DHS) considers levees to be part of the Nation’scritical infrastructure and collaborates with corresponding public and private partners toidentify levees that present the greatest risk to the Nation. DHS also coordinates correspondingprotective programs that utilize an all-hazards approach to risks (considering manmade andnatural incidents). This collaboration highlights the importance of protecting and ensuring thesafety of the Nation’s levees with contribution from all levels of government and the privatesector. As demonstrated during Hurricane Katrina in 2005, however, breaching of levees and

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subsequent flooding is still a possibility regardless of elaborate protection and safety programs.It is, therefore, incumbent upon the city as the levee owner and operator to maintain aneffective emergency preparedness plan.

The city’s Emergency Operations Plan (EOP) addresses the planned response to extraordinaryemergency situations associated with disasters affecting Novato including the Hamilton Fieldlevee system. The plan also addresses integration and coordination with other governmentalagencies when required. The plan accomplishes the following:

Establishes the emergency management organization required to mitigate anysignificant emergency or disaster affecting Novato

Establishes the overall operational concepts associated with Novato’s EmergencyOperations Center (EOC) activities and the recovery process

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8.0 SITE SECURITYIn addition to natural hazards, criminal or terrorist acts may also pose a potential threat tolevees. Historically, terrorist groups have conducted surveillance of potential infrastructuretargets. These efforts can be conducted over many months or even years. Additionalsurveillance may be conducted immediately prior to the attack to assess any securityenhancements that have been implemented and to adjust the attack plan if necessary.Although there is no credible information indicating that terrorists have identified levees aspotential targets, levee owners and operators should be aware of the possibility of a terroristattack targeting levees and other flood risk reduction structures.

Awareness and continuous vigilance are vital to enhancing the security of levees and supportingfacilities. As such, suspicious activities should be immediately reported to the Novato PoliceDepartment. Levee personnel should be alert to the following signs of possible surveillanceattempts, particularly during periods of potential flooding or heightened national threatadvisories:

Presence of strangers or unknown vehicles in areas near or adjacent to the levee,particularly if observed over the course of multiple days.

Individuals in accessible areas open to the public who do not fit the normal profile orbehavior of walkers, joggers, boaters, or cyclists.

Persons using cameras, video devices, or optical equipment to photograph or diagramlevee structures or their support systems such as pumps, gates, electrical components,or communications facilities.

Unusual aircraft flyovers or boating activities such as uncommon low-altitude flights, orunusual recovering or tossing of items.

Cuts in fencing or gates, particularly to key areas of the levee structure with no resultingtheft, vandalism, or other petty criminal activity.

Unusual requests for information from persons approaching levee employees, friends,or family members; or calling, visiting, or sending e-mails with questions regarding theoperation of the levee.

Theft of marked vehicles, work clothes, or identification cards from levee personnel,contractors, or other authorized personnel.

The above list should not be considered all-inclusive, and personnel should use good judgmentand experience to identify activities that are deemed to be suspicious. Some of these activitiesare difficult to pinpoint, especially in recreational areas, since many of the items used insurveillance efforts are also commonly used by campers, hikers, and nature photographers.

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8.1 Specific Security MeasuresThe Hamilton Levee System is relatively unsecured because of the nature of the overalldevelopment of the area and the presence of the SF Bay Trail on the water side of the levee.However, as of 2014, pedestrian access along the levee access road has been discouragedbecause of the presence of the SF Bay Trail. Vehicle access has been prohibited since theoriginal construction and a vehicle gate is present at the south end of the levee. Signage hasbeen posted to notify the public of the restricted use of the levee access road. This signageshould be properly maintained. In addition, the city takes the following security measures tominimize unwanted use of the levee system:

General

Weekly/periodic patrols of the levee by maintenance personnel.

Pump Stations

Secure locks on entry gates when an operator is not present at the site.

Levee Embankment and Splash Wall

Secure and lock the levee access gate near P.S. #1 at all times. Secure and lock the closure gate – normally in the open position.

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9.0 TRAININGThe Public Works Department is responsible for training personnel to operate, maintain, andinspect the levee system. At a minimum, training or flood control exercises should be held atleast once a year. Emergency exercises are coordinated by the Novato Police Department andthe Novato Fire District. Emergency training exercises are important because they show newpersonnel how to do things like operate the closure gate, respond to levee changes, andinspect/patrol the levee during a flood. Training exercises also let you know how much timeand manpower is necessary to complete certain tasks. Important practical considerations andphysical limitations that could be easily overlooked in a plan become clearly exposed during anactual exercise.

9.1 Levee System Training RequirementsAt a minimum, periodic training should be performed for key Public Works personnel at leastyearly. Training subjects may include the following:

Physical operation of levee system features such as pumping stations, and closurestructures

Maintenance or repair of levee system features Emergency procedures/response Testing communications/SCADA system Levee system inspection procedures Safety procedures Dissemination of information to the public/general public outreach

A training log to record training sessions is provided in Appendix L

9.2 Emergency TrainingThe Novato Office of Emergency Services is responsible developing training opportunitiesassociated with emergency management. Those with responsibilities under the city’s EOP mustensure their personnel are properly trained to carry out these responsibilities. The best methodof training emergency responders is through exercises. Exercises expose responders topotential situations and events allowing them to become more familiar with the procedures,facilities and systems that they will actually use in emergency situations.

Exercises will be conducted by the EOS on a regular basis to maintain readiness. Exercisesshould include as many members of the City staff, Special Districts serving Novato and, aspossible, other public / private partners. Novato OES will document exercises by conducting acritique, and using the information obtained from the critique to complete an After ActionReport (AAR). This information will be used to develop a Corrective Action Plan (CAP) plan,revising standard operating procedures as necessary.

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10.0 COMMUNITY OUTREACHIt is important for property owners located on the land side of the levee system to understandtheir role and the City’s responsibilities related to the levee system. Homeowners locatedadjacent to the perimeter of the levee have a unique obligation to do the following:

Be aware of signs of localized seepage Properly handle and dispose of yard waste and other debris Properly inspect and maintain yard area drains Use only designated access points to the SF Bay Trail

The pamphlet So You Live Behind a Levee! What you should know to protect your home andloved ones from floods (2010, ASCE) provides helpful information to residents or perspectivebuyers of property in the Hamilton area. The pamphlet is available from the American Societyof Civil Engineers and can be downloaded from their website:http://content.asce.org/ASCELeveeGuide.html

10.1 Property Owner ResponsibilitiesSpecific property owner responsibilities are detailed in the next sub-sections.

10.1.1 Area Drain MaintenanceThe majority of the subdivisions built on the immediate land side of the levee embankmenthave internal yard drainage networks. Typically the network consists of buried 4-inch diameterdrain pipe and inlets at the surface. The lines typically run along each side of the house andeither connect directly to the storm drain system in the street or via a collector pipe that runsparallel with the sidewalk. Three or more surface inlets are usually provided for each drain line.

As part of regular home and yard maintenance, the inlets and grates should be checked andcleared of debris. Checking for signs that may indicate the drain lines are not functioningproperly. These signs include: excessive moisture of standing water near the inlets; or standingwater in the drain pipe (as observed from the inlets). If a drain line is suspected to be pluggedor otherwise not draining, a plumbing service can “snake” the line to clear any clogs orblockage.

10.1.2 Vegetation ManagementProperty owners adjacent to the levee should maintain vegetation including trees along thefence line. Vegetation shouldn’t extend beyond the fence line. This critically important as thereis very limited access at the levee toe. Cleared or trimmed vegetation waste must not bedumped over the fence onto the levee toe.

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10.1.3 Social Trails on Levee EmbankmentProperty owners and the public in general should avoid construction and the use ofunimproved trails or paths up the slope of the levee embankment. There are severalestablished access points along the levee alignment for public to access the SF Bay Trail.

10.2 City’s ResponsibilityThe City is responsible for overall maintenance and operation of the levee system as describedin previous sections. The City will also provide residents and the general public generalinformation regarding the levee system. The city maintains a page on its website dedicated tothe levee.

Screenshot of city website:

Other public outreach activities include public hearings or forums on levee topics; letters toresidents; pamphlets or handouts available at city offices. The Public Works Department worksclosely with the Central Administration and City Manager’s office regarding public informationand levee system status.

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10.3 Seepage Observations and NotificationsAs described in Section 2.1.2, evidence of seepage at select locations was discovered byresidents and city staff in early 2008. The initial seepage observations were coincident with theprimary construction phase of the Hamilton Wetlands Restoration Project (HWRP) whichincluded the hydraulic placement of several million tons of dredged material. More recentseepage observations have been made since April 2014 when the former San Pablo Bay outerlevee was breached as part of the HWRP.

Seepage problems may or may not be identified during routine inspections and typically isidentified with input or notification by the impacted residents or property owners. Localizedseepage typically manifests itself at the properties located along the inboard toe of the levee.The Public Works Department shall respond to homeowner notification or complaints andperform the activities described in Section 4.5.1. As part of the seepage investigation anddetermination, the property owners will be requested to do the following:

Inspect area drains and ensure proper function. Inspect and check irrigation systems for leaks and to ensure proper function and

watering frequency. Inspect and check the water service line and the sewer lateral for leaks (assistance from

the water district and sanitary district may be available). Maintain a log or diary for a period of time noted any changes to moisture conditions,

health of plants or ground covers.

Localized seepage investigations should involve representatives from the both Engineering andMaintenance Divisions. Depending on the results of the actions described above, furtherinvestigations may be required such as installation of monitoring wells/piezometers. Regardlessof the results of the initial investigation, provide follow up reporting to the EngineeringManager and Public Works Director, and possibly the Public Communication Coordinator.

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Appendices follow

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APPENDIX A

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APPENDIX B

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Levee As-builts

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Pump Station As-builts

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Seepage Collection As-builts

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APPENDIX C

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APPENDIX D

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APPENDIX E

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APPENDIX F

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APPENDIX G

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APPENDIX H

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APPENDIX I

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96


APPENDIX J

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APPENDIX K

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APPENDIX L

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res4875

CITY COUNCIL OF THE CITY OF NOVATO

RESOLUTION NO. ________

RESOLUTION OF THE CITY COUNCIL OF THE

CITY OF NOVATO ADOPTING THE HAMILTON

FIELD LEVEE OPERATIONS AND MAINTENANCE

MANUAL AND AUTHORIZING THE CITY

MANAGER TO IMPLEMENT THE MANUAL

WHEREAS, the Federal Emergency Management Agency (FEMA) for purposes

of the National Flood Insurance Program (NFIP), will only recognize in its flood hazard

and risk mapping effort those levee systems that meet, and continue to meet, minimum

design, operation, and maintenance standards that are consistent with the level of protection

sought through the comprehensive floodplain management criteria established by Section

60.3 of the NFIP regulations; and

WHEREAS, Section 65.10 of the NFIP regulations describes the types of

information FEMA needs to recognize, on NFIP maps, that a levee system provides

protection from the flood that has a 1-percent chance of being equaled or exceeded in any

given year (base flood). This information, which must include among other documents an

officially adopted maintenance plan and operations criteria, must be supplied to FEMA by

the community or other party seeking recognition of a levee system at the time a study or

restudy is conducted, when a map revision under the provisions of Part 65 of the NFIP

regulations is sought based on a levee system; and

WHEREAS, FEMA issued a preliminary Flood Insurance Rate Map (FIRM) and

Flood Insurance Study (FIS) on March 24, 2014 showing a revised base flood elevation

(higher than previous) adjacent to the Hamilton Field Levee. The preliminary FIRM

indicates that the Hamilton Field Levee provides 1-percent level of protection. FEMA has

indicated that the revised maps will become effective in September 2015 before which time

all information required by the NFIP regulations must have been submitted to FEMA; and

WHEREAS, the previously prepared maintenance plan was originally developed

in 1997 and no longer meets the FEMA requirements nor accurately reflects the current

operations of the Hamilton Field Levee; and

WHEREAS, the Hamilton Field Levee System Operations and Maintenance

(O&M) Manual satisfies all of the requirements of FEMA and the NFIP regulations.

NOW, THEREFORE, BE IT RESOLVED that the City Council of the City of

Novato hereby:

1. The Hamilton Levee System Operations and Maintenance Manual (O&M Manual)

as submitted to the City Council is approved and adopted.

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2. The City Manager or his designee is authorized to submit the O&M Manual and all

necessary documents to FEMA and any other appropriate agency. In the event any

changes or modifications are requested by any agency, the City Manager, or his

designee, is authorized to make such changes and resubmit the document if

required.

3. The City Manager or his designee is authorized to implement the O&M Manual

once accepted by FEMA and to evaluate the O&M Manual periodically and make

updates as necessary.

* * * * * *

I HEREBY CERTIFY that the foregoing resolution was duly and regularly adopted by the

City Council of the City of Novato, Marin County, California, at a meeting thereof, held

on the 5th day of May, 2015, by the following vote, to wit:

AYES: Councilmembers

NOES: Councilmembers

ABSTAIN: Councilmembers

ABSENT: Councilmembers

Sheri Hartz, City Clerk

Approved as to form:

City Attorney of the City of Novato

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res4876

NOVATO PUBLIC FINANCE AUTHORITY BOARD

RESOLUTION NO. ________

RESOLUTION OF THE NOVATO PUBLIC FINANCE

AUTHORITY BOARD ADOPTING THE HAMILTON

FIELD LEVEE OPERATIONS AND MAINTENANCE

MANUAL AND AUTHORIZING THE CITY

MANAGER TO IMPLEMENT THE MANUAL

WHEREAS, the Federal Emergency Management Agency (FEMA) for purposes

of the National Flood Insurance Program (NFIP), will only recognize in its flood hazard

and risk mapping effort those levee systems that meet, and continue to meet, minimum

design, operation, and maintenance standards that are consistent with the level of protection

sought through the comprehensive floodplain management criteria established by Section

60.3 of the NFIP regulations; and

WHEREAS, Section 65.10 of the NFIP regulations describes the types of

information FEMA needs to recognize, on NFIP maps, that a levee system provides

protection from the flood that has a 1-percent chance of being equaled or exceeded in any

given year (base flood). This information, which must include among other documents an

officially adopted maintenance plan and operations criteria, must be supplied to FEMA by

the community or other party seeking recognition of a levee system at the time a study or

restudy is conducted, when a map revision under the provisions of Part 65 of the NFIP

regulations is sought based on a levee system; and

WHEREAS, FEMA issued a preliminary Flood Insurance Rate Map (FIRM) and

Flood Insurance Study (FIS) on March 24, 2014 showing a revised base flood elevation

(higher than previous) adjacent to the Hamilton Field Levee. The preliminary FIRM

indicates that the Hamilton Field Levee provides 1-percent level of protection. FEMA has

indicated that the revised maps will become effective in September 2015 before which time

all information required by the NFIP regulations must have been submitted to FEMA; and

WHEREAS, the previously prepared maintenance plan was originally developed

in 1997 and no longer meets the FEMA requirements nor accurately reflects the current

operations of the Hamilton Field Levee; and

WHEREAS, the Hamilton Field Levee System Operations and Maintenance

(O&M) Manual satisfies all of the requirements of FEMA and the NFIP regulations.

NOW, THEREFORE, BE IT RESOLVED that the Novato Public Finance

Authority Board hereby:

1. The Hamilton Levee System Operations and Maintenance Manual (O&M Manual)

as submitted to the Board is approved and adopted.

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F-5 3.

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Typewritten Text

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2. The City Manager or his designee is authorized to submit the O&M Manual and all

necessary documents to FEMA and any other appropriate agency. In the event any

changes or modifications are requested by any agency, the City Manager, or his

designee, is authorized to make such changes and resubmit the document if

required.

3. The City Manager or his designee is authorized to implement the O&M Manual

once accepted by FEMA and to evaluate the O&M Manual periodically and make

updates as necessary.

* * * * * *

I HEREBY CERTIFY that the foregoing resolution was duly and regularly adopted by the

Novato Public Finance Authority Board, Marin County, California, at a meeting thereof,

held on the 5th day of May, 2015, by the following vote, to wit:

AYES: Boardmembers,

NOES: Boardmembers.

ABSTAIN: Boardmembers,

ABSENT: Boardmembers,

Sheri Hartz, City Clerk

Approved as to form:

City Attorney of the City of Novato

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