SUBDIVISION IMPROVEMENT MANUAL

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Effective: January 7, 2008

David A. BrunkhorsL, P.E.. R.S . O ttawa Co unty Engineer TaUFree; (800) 788~8803

315 Mad L~ OH Street Phone: (419)73+ 6777 Port C!inwn, Ohio43452 FLlX: (4 /9 )734-6768

http:// www.co.ottawa.on.us

Table of Contents

County Engineer Message Page 1

Foreword Page 2

Acknowledgement. ' " , ,. Page 3

Section I - Survey Requirements

A. General Comments ' " Page 4 B. Rights-of-Way Page 4 C. Monumentation Page 4,5 D. Legal Descriptions Page 5,6

Section II - Pavement Design

A. General Comm ents Page 7 B. Determination of Required Improvements Page 7 C. Construction Procedures / Materials Page 7 D. Street Construction Standards Page 7,8 E. Turn-Around / Intersection Standards Page 8,9 F. Curb and Gutter Standards Page 9

Section III - Drainage Requi rements

A. Storm Water Management. Page 10-15 B. Storm Water Runoff Control Page 15-17 C. Erosion / Sedimentation Control Page 17,18

Section IV - Util ities

A. Non-Governmental Utilities and Easements Page 19

Section V - Fees

A. Plat and Improvement Plan Review Fees Page 20 B. Inspectio n Fees Page 20

Appendix

A. Ottawa County Storm Drainage Des ign Worksheet. ITEM A B. Precipitation Intensity Estimates ITEM B C. Maintenance District Summary ITEM C D. Right-of-W ay Detail (RW-40 ) RW-40 E. Right-of-Way Detai l (RW-50) RW-50 F. Right-of-Way Deta il (RW-60) RW-60 G. Monument Box Detail (MB-1) MB- 1 H. Monument Box Detail (MB-2) MB-2 I. Concrete Monument Detail (CM-1) CM-1 J . Benchmark Monument Detail (BM-1) BM-1 K. Pavement Design Standard Drawing (TPS-A) TPS-A L. Pavement Design Standard Drawing ( I PS-B) TPS-B M. Pavement Design Standard Drawing (TPS-C) TPS-C N. Cul-De-Sac DetaiL CDS-1

MESSAGE FROM THE OTTAWA COUNTY ENGINEER

The Manual of Subdivision Improvement Standards for Ottawa County, which follows, is the culmination of much work by the Tec hnical Staff of the Ottawa Coun ty Engineer's Office and in consultation with many other entities having a stake in the develo pment of new infrastructure for subdivisions in Ottawa County. Said Manual should be considered as a living document subject to upgrade , revision and addition as deemed necessary by situations as they occur, and changes in the app licable technology.

This document shoul d be construed to be the guidel ine expected by the Ottawa County Engineer's Off ice for desig n purposes for the rights-of-way, streets, sto rm drainage, storm water management and utility locations attendant thereto, whether the proposed rights-of-way or easements are to be publicly or privately maintained . Please note that those matters pertaining to the provision of potable water and sanitary sewer service in areas under the auspices of the Ottawa County Sanitary Engineer or a similar public entity would be covered by the ir respective design stand ards, and those requirements are to be incorporated into the final plans and framework of rights-of-way and easements set forth herein.

If questions arise regarding the standards set forth herein, the Technical Staff of the Ottawa County Engineer's Off ice and myse lf are available to provide answers and guidance as requested.

David A. Brunkhorst PE, RS Ottawa County Engineer

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SUBDIVISION IMPROVEMENT STANDARDS

FOREWORD

The Ottawa Regional Planning Comm ission admin isters the Ottawa County Subdivision Regulations, which establishes certain standards pertain ing to the basic parameters for the subdivis ion of land within the boundar ies of Ottawa County, Ohio. The Subdivision Improvement Standards, as promulgated herein under the auspices of the Ottawa County Engineer, are intended to provide guidance and the acceptable procedures pertinent to the des ign criteria for various street options, drainage requirements and utility place ments associated with the development of a parce l regardless of whether the improvements ultimately are taken over by a responsible public entity or remain under the private purview of the developer or a subsequent entity such as a Homeowners Association. The standards for each option are the same under either scenario as to the preparation, submittal , review and any associated construction that occurs in concert with the project as proposed . While certain improvement requirements may not need to be constructed if private maintenance of the streets and rights-of-way is pursued, the design and subsequently approved improvement plans will need to conform to these standards as if it would be under public maintenance and control.

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SU BDIVISION IMPROVEMENT STANDARDS

ACKNOWLEDGEMENT

The Ottawa County Engineer wishes to recogn ize the following individuals for their dedication of time and effort in 2006 - 2007 for the research and development of this document.

J. Dale Barnes, E.I., S.1. Michael C. Brough

JulieAnn Frias Ronald P. Lajti, P.E., S.1.

Jeffery L. Underwood, P.S. Michael J. Wittman , P.S.

This manual was created after many hours of resear ch and meetings to discuss the various items within. The original publication date of this manual is January 2008.

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SECTION I - SURVEY REQUIREMENTS

A. General Comments:

Only Professional Surveyors and Professional Engineers registered in the State of Ohio shall provide the required surveying and engineerin g services. All surveys, legal descriptions and survey plats, shall conform to Chapter 4733 of the Ohio Administrative Code and the Ottawa County Legal Description Review GUidelines .

B. Rights-of-Way:

Not every existing right-of-way in Ottawa County meets the sixty-foot (60') minimum as required in the Ottawa County Subdivision Regulations. For ease in design for transitions to new streets from a street that is less than a sixty-foot (60') right-of way, it is recommended that a right-of-way grant equaling one-half (1/2) of the deficiency be made in concert with the new subdivision to bring the existing right-of-way to sixty-feet (60'), thirty-feet (30') on each side of the existing centerline. Please refer to standard drawings RW-40, RW-50 and RW-60 for further information.

C. Monumentation:

1. Paved Streets: All street centerlines shall be monumented in accordan ce with Section 523 of the Ottawa County Subdivision regulations. Monumentation shall consist of a minimum :X" diameter by 30" long iron pin set in a monument box approved by the Ottawa County Engineer. Please refer to standard drawings MB-1 and MB-2 for approved monumentation for paved streets. Monumentation to be set after paving is completed and prior to final plat approval by the Ottawa County Engineer.

2. Unpaved Streets: All street centerlines shall be monumented in accordance with Section 523 of the Ottawa County Subdivision Regulations. Monumentation shall consist of a minimum :X" diameter by 30" long iron pin set in concrete. Please refer to standard drawing CM-1 for approved monumentation for unpaved streets. Monumentation to be set prior to final plat approval by the Ottawa County Engineer.

3. Benchmarks: All benchmarks shall be set in accordance with Section 523 of the Ottawa County Subdivision Regulations. Benchmarks shall consist of a 6" diameter concrete cylinder 36" in depth, cast in place, with a ferro-ma gnetic center and 3%" crowned brass or aluminum disk placed in the top. Please see standard drawing BM-1 for approved benchmark monumentation.

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a. All new subdivisions shall contain at least (2) permanent site benchmarks . At least one permanent site benchmark shall be established for each five hundred (500) feet of street length.

4. Alternate Benchmark Monumentation: Other durab le permanent benchmarks located within 500 feet from the site may be used. These benchmarks shall consist of an identifiable mark on a structure that is not subject to frost heave or accidental damage . These benchmarks must be approved by the Ottawa County Engineer's Office prior to their use. Railroad spikes in power poles are not permitted as permanent benchmarks.

5. At least one concrete benchmark conforming to standard draw ing BM-1 shall be set on site.

6. In an effort to keep benchmarks uniform throughout Ottawa County, the Ottawa County Engineer has decided to supply the disks for benchmark monumentation. Please contact the Ottawa County Engineer 's Office for the disks.

D. Legal Descriptions - Final Plat:

When preparing the final plat for submission to the Ottawa County Regional Planning Commission, the surveyor shall also prepare the following :

1. A copy of the Final Plat Checklist, completed by the surveying/engineering/design firm. This checklist is included in the Ottawa County Subdivision Regulations. This will reflect implied compliance with the Ottawa County Subdivision Regulations, and will also be an additional source for more timely reviews.

2. A digital, read only copy of the final subdivision layout in a .dwg or .dgn format. This digital copy will be used by the Ottawa County Engineer's Office for the purpose of checking closure and plat dimensions, and by the Ottawa County Auditor's Off ice / GIS Staff for more timely and efficient updates to the Ottawa County GIS system. Please avoid manually drafted plats. Manually drafted plats will require more review time and may incur addit ional review fees.

3. Legal descriptions prepared by the surveyor of record, for all non-lot parcels confined within the limits of the proposed subdivision boundary. Non-lot parcels include, but are not limited to: streets, waterfront areas, parks, easements, detention pond areas, etc.

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a. These descriptions must conform to Chapter 4733 of the Ohio Ad ministrative Code and also the Ottawa County Legal Description Review Guidelines.

b. Four (4) original copies of each description are to be prepared on either letter or legal size paper, preferably company letterhead, and sealed by the surveyor and signed and dated in ink other than black. One approved copy will be returned to the auth or for their records after the final plat is approved.

c. The approved non-lot parcel legal descriptions shall be retained and filed in the corresponding subdivision file in the Ott awa County Engineer's Office for future use . Future uses include , but are not limited to: public road dedications I vacat ions, property transfers of said non-lot parcels to a property owners association , etc.

i. Final plats will not be approved until all non-lot parcel legal descriptions have been approved .

4. A parce l clos ure report for the subdi vision perimeter, each individual sub-lot and inclusive non-lot parcel(s) confined with in the subdivision perimeter shall be completed and SUbmitted. Thi s will assi st the Ottawa County Engineer's Office in reducing the t ime to review the information. If a closure report cannot be gen erated, review time will increase and fees may be incurred .

The items cited in Section D Legal Descriptions - Final Plat, shall be submitted to the Ottawa County Engineer's Off ice in a legal size ma nila folder and lab eled with the subdivision name at the time of filing of the final plat.

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SECTIO N II: PAVEMENT DESIGN

A. General Comments:

This article has been prepared to control the manner in which the roadway system is arranged on the proposed land in order to promote the safe and efficient movement of traffic, to fulfill the needs of present as well as future population, and to integrate natural features and topography with the proposed streetscape as seamlessly as possible. Items in this section shall be implemented in accordance with the corresponding sections of the Ottawa County Subdivision Regulations . Any requirements of this document that are in conflict and are of greater constraints than the Ottawa County Subdivision Regulations shall be considered as the preferred method for design and construction. At this time , the Ottawa County Engineer can only suggest these more stringent requirements.. Reference Section 500 of the Ottawa County Subdivision Regulations for additional information.

B. Determination of Required Improvements:

Design standards shall be in accordance with the requirements and specifications of the Ottawa County Engineer and in accordance with the Ohio Department of Transportation Location and Design Criteria and the Pavement Design and Rehabilitation Manuals.

In cases where the Ohio Department of Transportation Manuals conflict with the Ottawa County standards, the Ottawa County Engineer shall determine the appropriate procedure. Reference Section 501 of the Ottawa County Subdivision Regulations for additional information.

C. Construction Procedures and Materials:

The minimum requirements for material and construction procedures shall be in conformance with the above-mentioned manua ls, the Ohio Department of Health, the Ohio Environmental Protection Agency, the Ottawa County Engineer, and the Ottawa County Sanitary Engineer. Reference Section 502 of the Ottawa County Subdivision Regulations for additional information.

D. Street Construction Standards and Specifications:

The following are the required minimum street construction standards. Please refer to typical sections A, 8, and C for standard typical section drawings . These typical section drawings can be found in the Appendix at the back of this document under TPS-A, TPS-B, and TPS-C respectively.

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The typical sections mentioned above contain what the Ottawa County Engineer considers to be minimum pavement cross sectional designs. All proposed pavement structures must be supported by an existing subsurface investigation and analysis. Said analysis will be based on the requirements of the Ohio Department of Transportation Specifications for Geotechnical Explorations. Pavement design shall be based on the Ohio Department of Transportation Pavement Design and Rehabilitation Manual. In the instance that a pavement design, created according to the Ohio Department of Transportation Pavement Design and Rehabilitation Manual, is of a lesser structural number than that of the Ottawa County Engineer's minimum pavement design section structu ral number, the Ottawa County Engineer's pavement design section shall be utilized for construction. All information, including testing results, pertinent to the proposed pavement design shall be submitted along with other necessary items for the improvements approval.

In the case of any questions as to street classification or type of street by use, the County Engineer shall make the final determination as to design and construction requirements. Reference Section 507 of the Ottawa County Subdivision Regulations for additional information.

E. Turn-Around and Intersection Standards and Specifications:

1. The cul-de-sac should be constructe d with a pavement radius of not less than forty- three (43) feet where open ditches are present, and up to a maximum of fifty-five (55) feet for curb and gutter streets as measured to the outside edge of the curb, except for industrial park roadways where the minimum radius shall be sixty (60) feet. The minimum radius to the right-of-way line should be sixty-three (63) feet except for industrial park roadways where it shall be eighty (80) feet.

2. Where minor residential streets have a change of direction of approxi mately ninety (90) degrees ("]," intersection) one of the following shall be provided:

a. A minimum radius of forty (40) feet measured from the intersection of the two street centerlines to the outer edge of the pavement (or edge of street surface) and satisfactory reverse at either end of same.

b. A curve with a street centerline radius of seventy-five (75) feet or greater; or

c. A satisfactory design combining the features of the above two provisions.

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3. All standard street intersections shall ordinarily be provided with radii of the back edge of the curb (or edge of street surface), which wi ll result in the space between said edge and the street right-of-way line along the straight part of the street being maintained on the corners.

See Section Detail CDS-1, which can be found under "Item N" in the Appendix at the back of this document, for cul-de-sac and intersection standard drawings. Reference Section 510 of the Ottawa County Subdivision Regulations for additional information.

F. Curb and Gutter Standards and Specifications:

Curbs shall be constructed according to standards established by ODOT "Standard Construction Drawings" or as modified in Section 507. Only ODOT "Type 3" curb and gutter will be accepted and approved by the Ottawa County Engineer. Reference Section 513 of the Ottawa County Subdivision Regulations for additional information.

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SECTIO N III: DRAINAGE REQUIREMENTS

A. Storm Water Management

Purpose: These design standards and specifications shall serve as minimum requirements for the care and treatment of surface water and drainage. These procedures and regulations shall govern the development of all new and/or modified drainage systems. The development of such drainage systems shall include the conveyance of surface water to an adequate outlet capable of carrying the flow. All proposed improvements shall be in accordance with the Ottawa County Subdivision Improvement Standards and the Ohio Department of Transportation Construction and Material Specifications. All proposed improvements are subject to approval and/or alterations by the Ottawa County Engineer prior to the construc tion of any portion of the drainage system.

1. FEMA (Federal Emergency Management Agency) regulations shall be strictly followed for all developments . Impacts on floodway and floodway fringes shall be analyzed and accounted for. Filling in a flood plain requires a permit from the Ottawa County Building Inspection Department. Flood boundaries shall be shown on plans along with 1DO-year storm elevations. All necessary CLOMRs (Conditional Letter of Map Revision), LOMRs (Letter of Map Revision), or LOMAs (Letter of Map Amendment) shall be secured from FEMA prior to construction of buildings can commence.

2. Included with submitted improvements shall be an overall site drainage map delineating each contributing area and subsequent collection points. Site drainage map shall establish final min/max grading elevations at all lot set back line intersections. A professional surveyo r shall verify elevations upon completion of lot development.

3. Drainage design will be adequate to support the entire contributing watershed for present as well as future development.

4. When proposed drainage improvements utilize an existing storm sewer or open ditch, cross sections and profiles shall be submitted detailing existing conditions at least 500 feet downstream from the point of impact. The outlet stream for the development may need improve ments prior to development. An approved plan and County inspection is required when cleaning any ditch required for plat approval.

5. If future plat extensions anticipate utilization of the same drainage system. the overall drainage plan shall be submitted with the initial plat proposal.

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6. All open ditches outside of the normal right-ot-way shall be protected with a minimum twenty (20) foot drainage easeme nt.

a. The easement(s) shall be shown on the final plat and the improvement plans and labeled as "Permanent Drainage Easement" , and shall detail who will assume maintenance respons ibilities.

b. A letter by said maintenance authority accepting maintenance responsibility shall be required for final plat acceptance.

c. All other drainage easements shall be deemed private, however, maintenance responsibility (individual homeowner, home owners assoc iation, etc.) must be described on the construction plans and final plat.

7. The following shall serve as minimum requirements for plans and engineering calculations for the on-site drainage:

a. The total tributary drainage areas entering the improved area shall be shown.

b. Times of concentration, intensity, and runoff coefficients used for determini ng runoff.

c. Discharge volume in cubic feet per second, velocity, and additional data needed to establish that the drainage system will direct the flow to the approved adequate outlet.

d. The plan and profile of all drainage conduits from initiation to where the system discharges into the adequate outlet.

e. Size and type of all drainage improvements including all drainage structures.

f . Sufficient contours and grading details to show that the proposed improvements will function adequately.

g. All required approved permits , including but not limited to, NPDES, Right of Way , and any needed legal easements.

8. Subsurface Drainage

a. For roadway structures and slope stabilization, pipe under-drains are to be used as required by the geotechnical report.

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b. In the design of the pipe under-drain system, consideration shall be given to the type of pipe used, the filter material , and the surrounding soils that are to be drained in order to avoid clogging and achieve adequate hydraulic capacity. (Refer to the Appendix Items K, L, and M at the end of this document for the street construction standards and specifications).

c. The design and construction of all subsurface drainag e systems shall be reviewed and approved by the Ottawa County Engineer.

9. Downspout Drains

a. Roof drains and sump pump pipes may be installed and connected to the storm drainage system. Drain lines shall empty into the nearest catch basin or manhole to prevent excessive pipe sizes for the downspout drain lines. Downspouts may not directly or indirectly outlet onto a public roadway. In lots where slopes are to the rear, drain pipes may be outletted to a drainage swale, storm sewer, or other method as available and if approved.

b. Any and all pipes connected to an existing drainage system shall be constructed under the inspection and approval of the Ottawa County Engineer while maintaining the appropriate permits.

c. The minimum size for any collector line shall be no less than six inches.

10. Open Ditches

a. The minimum slope of open ditches shall be one tenth of one percent (0.1 0%). All ditches , slopes and other areas disturbed by construction shall be seeded and mulched per NPDES Permit.

b. The minimum dimensional requirements for open ditches shall be a two (2) foot bottom width, two (2) foot depth (for drive pipe coverage), with side slopes graded to a two to one slope unless otherwise directed by the Ottawa County Engineer . (Note that slopes flatter than two to one are preferred for mowing purposes). Drainage swales that convey water specifically for and between lots may be exempt from this item.

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11 . Storm Sewer Design

a. Where a storm sewer system is to be constructed within a roadway where curbs are installed, catch basins with curb inlets shall be required in accordance with the design specifications and standard drawings of the State of Oho Department of Transportation . "Type 3" curbing is required for the option of locating driveway accesses.

b. Where a storm sewer system is to be constructed and there are no curbs being installed or the storm sewer system is being installed away from the roadway, there shall be a drainag e swale over the storm sewer system draining to an inlet basin. An inlet shall be placed at each lot corner and/or spaced according to these regulations and of the type specified by Oo D.OoT.

c. Storm sewer taps shall be provided for all lots unless basements and crawl spaces are prohibited by plat recitation. Taps shall have an outlet to the main storm sewer system for the development and may not be outletted directly to open ditches of rear yard drainage.

d. Storm sewer taps shall be a minimum of 6" diameter and shall be installed to the right of way line or on to the lot if installed prior to single lot development. Taps shall be placed at least 6 inches above main line sewers and into structures whenever possible.

e. Storm sewers shall be designed to flow just full for the 5-year intensity-duration-frequency curve. Open ditches, gutters, and/or catch basin inlets shall be at or above the hydraulic grade line for a 1O-year frequency storm.

f. The minimum velocity at full flow conditi on shall be no less than 2 feet per second.

g. No storm sewer shall be less than twelve inches in diameter, excluding metering devices.

h. Driveway pipes shall not be less than twelve (12) inches in diamete r and twenty-four (24) feet in length, shall be reinforced concrete pipe, shall be constructed as to maintain the flow line of the ditch, and such installation shall be approved by the Ottawa County Engineer .

i. All storm drainage systems under pavement shall be reinforced concrete installed with the appropriate bedding and backfill material.

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j. No major storm lines shall be placed in rear yards (for accessibility reasons).

k. Plan cross-sections shall show all crossovers catch basins manholes, and any additional structures - both existing and' proposed.

12. Appurtenances to Storm Drainage Design

a. Manholes or catch basins shall be installed at all changes of size, grade, and/or alignments. Location of manholes and catch basins is preferred to be every 350 feet on center measured horizontally along the centerline of pipe.

b. The minimum cover for drainage pipes under pavement shall be eighteen (18) inches from finish grade to the crown of the pipe.

c. Crossovers shall have a 0.5% minimum grade when possible, unless otherwise approved by the Ottawa County Engineer.

d. All drainage pipes laid under pavement or within a one to one down slope from of the edge of the pavement shall be bedded, backfilled with granular material, and mechanica lly tamped per O.D.O.T. specifications.

e. Corrugated High Density Polyethylene Pipe (HDPE), Item 707.33 (Type S), may be used in areas that have a minimum of two (2) feet of cover and must begin and end in an enclosed structure. HDPE may not be used under roadway pavement. Any usage of this product must be pre-approved by the Ottawa County Engineer.

f. Corrugated metal pipe will be permitted only when being used as a restriction in a detention facility.

g. Developer shall receive a permit from the Ottawa County Engineer's office for the installation of any necessary storm water pipe under any access to and from the development by way of county or township road. The permit shall list the proper size and grade of said pipe appropriate to the drainage system requirements.

h. Rock channel protection will be required at all sewer and culvert inlets/outlets.

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i. All drainage structures and appurtenances shall comply w ith applicable County specifications and/or the most current edition of O.O.O.T.'s Construction and Materials Specifications and Standard Construction Drawings. The Ottawa County Engineer shall arbitrate any discrepancies between said standards.

B. Storm Water Runoff Control

1. The design of storm sewer systems will be based upon the "Rational Method" using the equation Q =CiA and the "Manning Formula" (where A is less than 200 acres). Areas greater than 200 acres shall be designed using the State of Ohio Bulletin Number 43 and compare with Bulletin Number 45 Floods in Ohio or Soil Conservation Service Technical Release Number 55, 2nd edition.

a. The rainfall intensity, "I", will be taken from the appropriate curve for the Catawba Island, Ohio area as published in the "Precipitation-Frequency Atlas of the United States" NOAA ATLAS 14, Volume 2, Version 3 - 2004. A copy of those values and necessary interpolated values is supplied in the Appendix of this manual under Item B.

b. Time of Concentration (Tc) shall be determined by the use of the USDA Urban Hydrology for Small Wate rsheds TR55 method. (Assumed Tc values are not acceptable).

c. Runoff coefficients for the rational method shall be listed on the Ottawa County Storm Drainage Design Worksheet , found under Item A of the Appendix, and will be subject to approval by the County Engineer.

d. Catch basin type and spacing shall be designed using the 2-year intensity-duration-frequency curve found under Item B of the Appendix.

e. Complete drainage calculations shall be submitted for pipe size determinations, 10-year hydraulic gradient checks, and catch basin type and spacing designs. All culverts will be designed for a 10­year frequency storm with a hydraulic gradient check for a 25-year storm. Check with County for availability of hydraulic data on receiving streams.

f. Storm sewers and culverts shall be designed to conform to the requirements of Item 603 of the current State of Ohio, Department of Transportation Construct ion and Material Specifications.

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2. Detention/Retention Basin Design

a. The County shall require detention/retention facilities and the allowable flow out will be limited to the existing 5 year intensity storm for existing conditions of the proposed site.

b. The detention faci lity shall store the proposed flow from a 25-year intensity storm.

c. Basins in proposed residential areas should be aesthetically pleasing.

d. Dry basins with bottom widths greater than forty (40) feet shall have subsurface drainage at no more than twenty (20) foot spacing to dry the basin after storm water discharge. If elevations do not permit the use of subsurface drainage, the engineer shall show such in the design calculations. If a lift/pump station is necessary due to grade constraints, pump sizing and station location shall be subject to approval by the Ottawa County Engineer.

e. Design shall show impact of water surface on storm events up to and including the 1DO-year storm.

f. The number of basins shall not exceed two (2) unless otherwise approved by the maintaining authority and shall be on lands owned (owned or have right of access by easements) by the maintaining authority.

g. When utilizing a parking area for detention facilities , the depth of water retained shall not exceed 6", unless otherwise approved by the County Engineer.

h. Meter line size shall be based off of "Q flow" and not "Q avg".

i. See storm water drainage design worksheet located under "Item A" in the Appendix at the end of this document. Submit a copy of completed work sheet with subdivision improvement plans in order to decrease review time .

j . Wet basins shall have a 6 feet minimum wide safety ledge around the perimeter two (2) feet below the normal water surface elevation .

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k. All new subdivisions shall be placed into a permanent drainage maintenance program as specified under Section 6131.63 of the Ohio Revised Code. Refer to "Item C" in the Appendix located at the end of this document for references to Sectio ns 6131.63 and 6137 of the Ohio Revised Code.

I. The drainage maintenance fund shall be created according to Section 6137 of the Ohio Revised Code. The said fund shall be responsible for the entire drainage system as des igned and approved by the County Engineer, and shall be the responsibility of an authority as assigned . All lot owners within the said subdivision shall be termed the benefiting parcels of the said storm sewer system within the maintenance district.

m. Maintenance funds shall originate by contai ning a minimum of 5% of the initial required construction costs of all items as listed above. The Ottawa County Engineer reserves the right to modify the minimum fund amount on a case-by-case basis . Said fund reserves shall be in place prior to final plat acceptance.

n. Ownership and/or easements for the purpose of maintenance shall be granted to the maintaining authority for access to all storm water control structures and facilities for which the maintaining authority is assuming permanent maintenance responsibility. Such easements shall be noted on the final plat.

C. Erosion and Sedimentation Control

1. The following procedures are hereby specified to help minimize erosion and sedimentation problems encountered during the development process, and comply with EPA NPDES requirements. Meeting the following standards and criteria does not relieve any person or f irm from liability for erosion or sediment damage to another person's property.

2. Review Procedures

a. All subdivisions shall be reviewed by the appro priate agency to see if control measures are needed to minim ize water, erosion and/or sediment problems.

b. An erosion and sedimentation control plan shall be submitted for all subdivis ions containing more than ten lots, the construction of a street , or as required by NPDES regulations. Approved NPDES permit and a copy of the submission to OEPA shall be submitted with plat during the review process.

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c. Subdivisions that are a portion or phase of a larger proposed allotment, shall submit a tentative erosion and sediment control plan for the entire allotment.

3. General Guidelines

a. W hen originating upgrade of proposed construction site, runoff shall be intercepted and/or diverted away from the construction site so as to minimize the amount of potential flow over the area of disturbed soil.

b. Sediment basins, debris or desilt ing basins, silt fences, and/or silt traps shall be inspected by the NPDES author ity and certified to the Ottawa County Engineer as installed per NPDES permit.

c. Terraces, diversions and/or grassed waterways should be installed and mainta ined as part of the water disposal system to further cont rol water and sediment damage .

d. Permanent vegetation, including the use of sod, and structures should be installed and maintained as soon as possible to help control water and sediment damage.

e. Erosion contro l is to be installed prior to comple tion of const ruction. When work is being done during slow growing or dorman t seasons, alternate and/or temporary solutio ns shall be utilized.

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SECTION IV: UTILITIES

A. Non-Governmental Utilit ies and Easements

1. Location of non-governmental utility easements shall be outside the road right-of-way and shall be subject to the approval by the Ottawa County Engineer and/or the Ottawa County Sanitary Engineer. Utility easements may also be located along the front lot line or on the rear or side lot lines as necessary for utility facilities (electric, telephone, gas, television cable, street lighting wires, conduits and cables). Easements shall give access to every lot, park or public grounds , including pump or lift stations. Such easements shall be a minimum of ten (10') feet wide.

2. Electric and telephone service shall be provided within each subdivision. Gas service may be required where reasonably access ible. Utility facilities shall be constructed underground, according to the standards of the appropriate utility company.

3. The developer shall comply with Section 3781.27 of the Ohio Revised Code. Recommendations on the proposed location of all underground utility facilities should be sought where practical from the utility companies serving the area by the developer prior to submitting the Preliminary Drawing. The developer shall be responsib le for contacting the utility companies to determine what size and type conduit would be needed.

4. Preliminary Drawings shall include a separate page showing location of proposed utilities, including size and type of conduits for road crossings. The Ottawa County Engineer shall approve all conduits for road crossings.

5. All underground utility facilities shall be instal led throughout the subdivision, including all right-of-way crossings and serv ice to every lot in the subdivision, prior to acceptance of the Final Plat. The intent is to have all utility service taps and road crossings, including conduits, in place prior to paving the roadway surface .

6. The Final Plat shall include specific easement recitations regarding the utility faci lities.

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SECTION V: FEES

A. Plat and Improveme nt Plan Review Fees

The cost of reviewing and checking the construction drawings submitted to the Engineer for approval shall be paid by the developer at the rate of $50.00 per hour to cover such items as employee benefits, engineering service , office expense, etc. The County Engineer will mail an itemized statement to the developer/owner and to the consultin g engineer/surveyor with timely payment expected from one or the other. The minimum charge will be $100 .00 per review and all fees must be paid prior to the Ottawa County Engineer signing the final construction drawings.

B. Inspection Fees

The cost of field inspection by the Engineer shall be paid by the developer at the following rates:

Single Field Inspector - $75.00 per hour Two-Person Inspection Crew - $125.00 per hour

The Single Field Inspector will be utilized to observe and verify basic construction and installation processes associated with a subdivision development.

The Two-Perso n Field Inspection Crew may be utilized to insure compliance of installed infrastructure in conformity with the approved specific Subdivision Improvement Plans and the requirements of these Standards.

The County Engineer will mail an itemized statement to the deve loper/owner and to the consu lting engineer/surveyor. The payment is required prior to signing the record plan.

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APPENDIX

OTTAWA COUNTY STORM DRAINAGE DESIGN WORKSHEET

All prec ipitation intensity values are supplied for you on the following sheet

1 GROSS AREA (At)

2 PAVEMENT AREA ::::

3 BUILDING AREA ::::

4 TOTA L IMPERVIOUS AREA (Ai) ::::

5 NET PERVIOUS AREA (Ap) ::::

6 WEIGH TED C =c, =((( C · ~ )+ ( C* Ap ))/ At) ::::

7 ALLOWABLE Q INTO EXISTING SYSTEM

Sheet Flow

Mannings Roughness Coefficie nt

Flow Length (total L <= 100 ft), tt

Two-yr 24-hr Rainfall, inches

n=

L =

P2 :::: 2.22

Land Slope, ftfft s=

0.007 (nL)08

T,

P20\ 04

Shallow Concentrated Flow

Surface Descript ion (paved or unpaved)

Flow Length , ft L =

Watercourse Slope S=

Average Velocity (appendix F of TR 55) V =

T, = U3600V

Total T , =

note: i 5 is based on time of concentration (T cJ using TR55 method lis ted above. Use i 5 values from attached

intensity sheet. Assumed T c values are not acceptable.

Hrs

Min

Hrs

Min

S.F.

S.F.

SF

SF x 0.95 :::: S.F.

SF. x 0.15 = S.F.

Table 3-1 Roughness coefficients (M anning' s n)

for sheet flow

Surface descri ption n \I

Smooth surfaces (concrete, aspha lt,gravel ,

or bare soil) 0.011

Fallow (no res idue ) 0.05

C ult ivated soils : Residue cover :520% 0.06

Residue cove r >20 % 0.17

Grass:

Short grass prairie 0.15

De nse grasses 2/ 0.24

Bermudagrass . 0.41

Range (natural ) .. 0.13

Wood s:)/

Light underbrush ... ..... 0.40

Dense underbrush . 0.80

I The n values arc a compos ite of information compiled by Engma n

(19 86)

1 Includes specie s such as weep ing lovegras s, bluegras s, buffalo

grass, blue grama grass . and nauve grass mixtures.

l Wh en se lec ting 11 • consider cover to a height of about 0.1 ft. This

I> the onlv part o f the plant co ver that will obst ruc t sheet flow.

::::

= cfs0.15 X is x (Atl43560) Q allow =CisA - - - - - - ­

ITEM A

--------

8

9

DETENTION VOLUME REQUIRED

te

(min)

i25

(in/hr) C."A

(acres)

Qin

(Q25)

Qout

(Qallow) Qin - Qout

= R

Detenti on Vo lume R x te x 60 (cubic feet )

10 5.49 15 4.52 I 20 4.08 25 I 3.63 30 3.19 40 2.82 50 2.44 60 2.07 80 1.8

100 1.54 120 1.27 140 I 1.15 160 1.02 180 0.9 210 0.84 240 0.78 270 0.72 300 0.65 330 I 0.59 I 360 I 0.53 I

If peak storage volume is not reached within the 6 hr. time period in the above table, continue this procedure until peak storage volume is reached. Rainfall Intensity Chart - see attached sheet - information gathe red from NOAA for Catawba Island 1 SW, Ohio http /lhdsc.nws.noaa.govlhdsclpfdslindex .html

Water Quality Volume 0NQ v) fl3

Water Quality Volume, if applicable, shall be designed in accordance with the Ohio EPA Permit Number OHC000002 Part 1/I,G.2,e, All calculations shall be submitted with design for review.

DETERMINATION OF DESIGN DETENTION VOLUME

AREA (S) END AR EA OF SECTION (W) LENGTH (fl) VOLUME (fl") 1 2 3 4 '00 I

Design Detention Volume (inc lUding WQv if applicable)

Required Detent ion Vo lume (inclUding WQ v if applicable)

10 DETENTION DESIGN METER LINE CHECK (CULVERT ANALYS IS)

::Length of mete r line fl

:: %Slope of meter line

fl

fl2

Size of mete r line = in ,

Area =

ITEM A

------

Pipe n value PVC = 0.010 CMP = 0.024 Others = 0.013

=

Ke value (usually 0.5) =

Assumed max head (H) = ______ft

Hydrualic Radius (R) ______ft _____ ft

V2/2g 3H = (1 + Ke + 29n2L / (R4/ ) ) , solve for velocity

Assumed Head (H) (ft) H x 20

1 + Ke +

(29n2L / (R4i3) ) V2 V

Area of Pipe (A)

Flow (0)

Oavg = Sum 0 / number

0.5 32.2 1.0 64.4 1.5 96.6 2.0 128.8 2.5 16 1 3.0 193.2 3.5 225 .4 4.0 257.6

Design Flow (0) = VA cfs

Allowable Flow (OaIlDw) cfs

ITEM A

PRECIPITATION INTENS ITY ESTIMATES (IN/HR ARI MINIUTES

(YEARS) 5 10 15 20 25 30 40 50 60 80 100 120 140 160 180 210 240 270 300 330 360

1 3.84 2.98 2.44 1.61 0.98 0.58 0.41 0.24

2 4.57 3.56 2.91 1.94 1.19 0.71 0.50 0.29

5 5.50 4.27 3.49 3.12 2.76 2.39 2.09 1.80 1.50 1.30 1.10 0.90 0.81 0.72 0.63 0.59 0.54 0.50 0.46 0.41 0.37

10 6.23 4.81 3.95 274 1.74 1.05 0.75 0.43

25 7.19 5.49 4.52 4.08 3.63 3.19 2.82 2.44 2.07 1.80 1.54 1.27 1.15 1.02 0.90 0.84 0.78 0.72 0.65 0.59 0.53

50 7.91 5.99 494 3.53 2.33 1.45 1.03 0.61

100 8.64 6.50 5.38 4.88 4.39 3.89 3.46 3.03 2.60 2.28 1.96 1.64 1.48 1.33 1.17 1.09 1.01 0.94 0.86 0.78 0.70

200 9.38 7.00 5.8 4.24 2.87 1.84 1.32 0.80

500 10.38 7.63 6.34 4.70 3.25 2.12 1.53 0.95

1000 11.12 8.09 6.75 5.06 3.55 2.35 1.71 1.07

INFORMATION GATHERED FROM NOAA ATLAS 14 - http://hdsc.nws .noaa·90v/hdsc/pfdslindex.html FOR CATAWBA ISLA ND 1 SW , OHIO (33-1353) 41.55 N 82 .85 W 590 FEET

BOLD Duration intensities are interpolated from data provided by NOAA ATLAS 14

~ m ~

1Il

CREATING MAINTENANCE DISTRICTS FOR NEW SUBDIVISIONS OHIO REVISED CODE REFERENCES

A. 6131 .63 - Public Watercourses Established by Agreement 1. All steps listed below are to be completed prior to the record ing of the

subd ivis ion plat wh ile the developer owns all lots . 2. Landowner/Developer agree to pay for and construct a drainage

improvement (subdivision) 3. Plans are deve loped and signed by a Professional Engineer. (Plans

and Subdivision Plat must show all easements necessary to perform main tenance).

4. Sign "Contract" with Cou nty Commissioners i. Plans for storm sewers , retention pon ds, outfall sewers

approved by County Engineer. ii. Mainte nance through 6137 will include all storm sewers and

appurtenances to the storm water plan as shown on the plans (laterals to individual homes not covered).

iii. Developers (so le owners of all parcels) , agree to waive the ma inten ance hearing.

iv. Develope rs (owners) release al l easements to the Com missioners.

v. Agreement can require a deposit to begin maintenance f und (optional one-year bond).

5. Boa rd of County Commissioners pass resolution accepting improvement , creating a maintenance district and filing a assessment schedule "Schedule of Landowners" with County Aud itor to establish a ma inten ance base for each benefiting parcel (can be a base determined by calculating actual storm water costs incurred by the developer).

B. 6137 - Ditch Maintenance Fund 1. 6137.02 - Creates Fund 2. 61 37.03 - annual maintenance assessment (% of original base

assessment - 20% limit) i. % of original assessment - listed as "special assessment" on

duplicates . ii. Max imu m limit in fund is 20% of original cost iii. Minimum assessment of two dollars. iv. Commissioners' annual resolution "if' fun ds are needed.

3. 61 37.05 - Use of Fund (Maintain the improvement to provide designed capacity)

i. County Engineer determines what work is necessary ii. Commiss ioners decide if County, contract , SWCD, etc. actually

performs work. 4 . 6137.10 - Additional assessment to landowner for repa ir of damages

due to negligent acts and admissions by landowner.

ITEM C

5. 6137 .1 2 - Maintenance Easements: Make sure subdivision plat allows for any easements necessary to maintain collection system, detent ion facilities, surface/subsurface outfall

6. Language is needed within plat's "Covenant of Restriction" informing lot owners of maintenance assessments.

ITEMC

---- --

PROPOSED STREET / INTER SECTION DETAIL

3D' FROM i

I, 0.-[0.­""- ,""­wrw

,

I 20' I, I~ '0 I~ , r:::1

I~ ' 0.­

I~

R/'W

'0.­

I ,

I, I =E /~

--E/P IR/'W

PROPOSED

R/'W

ADDITIONAL R/'W

-LEXiS~G-RDAD--_EE- //PP= -

R/'W r

ADDITI ONAL RIGHT-OF-WAY DETAIL (EXISTING 40' RIW)

DRAWN BY : J.D. BARNES, E.!., S.I APPROVED BY: DA BRUNKHORST, P.E., R.S.

REVISIONSonAWA COUNTY ENGINEER'S OFFICE f.--,..----I

315 MADISON STREET, ROOM 106 PORT CLINTON, OH 43452

(419) 734-6777

SCA LE" 1,. = 50' RW-40

PROPO SED STREET / INTERSECTION DETAIL

I 6 0 I ' II I

1 3 0..- 0..- 3I<, <, <, <, C1': W

I W C1':

I I

I 20' - -I I

I~ 0 C1':

H W (/)

o 0..­o

3 0' FROM ct1 C1': PROPOSED 0..- ADDITIONAL

' \ I r' \ R/YJ 5r l5

~~ >-L , 5{ ~ R/ YJ" " '\. '\. '\. '\. '\. ''\. '\... / / / / / / / '/ / / R/YJ-:z:::J

=~~ __~ ~__~~ __t ~~= EXISTING ROAD E/P-E/P ­

r R/ YJ R/YJ

1

ADDITIONAL RIGH T-OF-WAY DETAIL (EXISTING 50' RIW)

DRAWN BY: J.D. BARNES, E.!., S.I APPROVED BY: DA BRUNKHORST, P.E., R,S.

REVIS IONS onAWA COUNTY ENGINEER'S OFFICE \-------,----- -1

315 MADIS ON STREET, ROOM 106 PORT CLINTON, OH 43452

(419) 734-6777

SCALE 1" =50' RW-50

-- -----

PROPO SED STREET / INTERSECTION DETAIL

l I 1 6 01

I I

[

:3 (L I (L :3 <, <, I <, <, ~ w w ~

I , I

20 '

RIGHT-OF-WAY DETAIL (EXISTI NG 60' RIW)

DRAWN BY: J.D. BARNES , E.I., S.I APPROVED BY: DA BRUNKH ORST, P.E., R.S.

REVISIONS o n AWA COUNTY ENGINEE R'S OFFICE ~_~_-I

315 MAD ISON STREET, ROOM 106 PORT CLINTON, OH 43452

(419) 734-6777

SCALE: 1" = 50' RW-60

- - -

3/4"

41/4"1 1

II ~

V1

D 0 "':::1

1/2" H~~-L~-F~H--' f--61/8"-1

LID

1 7/8" l

121 /4"

/

f---­ ' 2 ' 14" -

1/2"J I I , I

: I I

\I \ I I

I \ I \ I , J \ I ,

3/8" I Ir I \

T >--- 8 1/2"-- --1 MONUMENT BOX

-

(EAST JOR DAN STD . BOX NO. 8340)

tl==71/4"~

11~61/2"~l i

STD LID FOR EAST JORDAN MONUMENT BOX NO. 8340

L. -. -.1

i '----- -j-­-­ --'i I I I I

I 4\" \J I I 1 I I

I I I I I I I I

3/4" (2) MIN. IRON ROD WITH CENTER PUNCH (MIN.)

NOTE : THE EAST JORDAN MONUMENT BOX FACILITATES TH E FASTENING OF THE LID BY A THR EADED BOLT THE FASTENIN G OF THE LID WITH A BOLT IS NEITHE R REQUIRED NOR DESIRED.

91 /4" DRAWN BY: M.J. W IDMAN, P.S.

APP ROVED BY: DA BRUNKHORST, P.E., R.S.

MONUMENT BOX DETAIL (EAST JORDAN 8340)

MB-1

REVI SIONS

SCALE: 2" =l '

o n AWA COUNTY ENG INEE R'S OFFICE !--­ ---,r---I 315 MADI SON STR EET , ROOM 106

PORT CLINTON , OH 43452 (419) 734-6777

STD. LID FOR NEENAH 31/8" X 3 1/8" MONUMENT BOX NO. R-1978-A3 r------------.,

LETTER r---------,IRECESSED 1/8" I II II II "1I

I I I I I I

I I I II

I

I L,

,-_..J

I I I I

r-i I I I I I I I I ~J L_..J

8'_'r".~~r---7 7/----r- f----- 6" - I ----r ­

1 1/2" J L 2 3/8"

LID

(2) PIC KHOL ES IN FRAME SIDEWA LL \

3/8 " l \ --L~

I

30

111 1 1 111 11 1 111 11 1

:111 =COMPACTED - -III-III

1 11 1 1I1 11111111 1

I '" , " , ,

1I 1 11111 1 1 111 11 1 1111

EARTHEN SUBGRADE =1 11 11-1 1 1-1 1 1­

1I 1 1 11I 11 1 1111 1 1 1111 , , , , , , , , ,

"61 /2 3/4" 0 MIN. IRON ROD WITH CENTER PUNCH (MIN.)

I

-----j

I

r- 1"

-------161/2"------­

T 11" -----4

MONUMENT BOX (NEENAH R-1978-A3)

NOTE: THE NEENAH MONUMEN T BOX FACILITATES THE FASTENING OF THE LID BY A THREADED BOLT. THE FASTENI NG OF THE LID WITH A BOLT IS NEITHER REQUIRED NOR DESIRED.

MONUMENT BOX DETAIL (I\IEENAH R-1978-A3)

DRAWN BY: M.J. WIDMAN, P.S. APPROVED BY: D.A. BRUNKHORST, P.E., R.S.

REVIS IONS o nAWA COUNTY ENGINEER'S OFFICE f----.,.---t

315 MADISON STRE ET, ROO M 106 PORT CLINTON, OH 43452

(419) 734-6777

SCALE 2" = l' MB-2

SURFACE 5/8" '" MIN. IRON PINWI

SURVEYORREFERENCE CAP 1/4" ±r =111 III . 1- ­

~II I III III IIII ~ · ~ ~1 11 1 1 1 1 1 1 1 1 1 - Il l- III ' ". ..1 1111111111 1111:I

=111 III I~II I IIIIII IIII . . .. 1I1I1111111 111

~ 1 1 1 1 1 1 1 1 1 1 1 1 1 LI . . . 11 111111111111

I III III . <1

TIII IIIIIIIII I

~~~ . TII IIIIIIIIIII <1

=11 1 II I I ·' ~ 1 1 1 1 1 1 1 1 1 1 1 1 1 JIIIIIIIIIIII " . . I- Ill- III

=111 III I '

I III 111.1l=Iillillilllil ~ - - - ' =111 1111 1111111 . -----1 . .1

II111 II1111I11

-a 11 111 " 1111 "1

I 11 1111 1111111 .1

4 1I11 1111111111

"I ~ II I~ ~ ~ III ~ ~ ~ 5/8" '" MIN.

II I1IIRO~ II ..1 111I 11I 1III111

II I III II ill ill

d <1

' 11 1==111== f-- 6"-1

UNDISTURBED GROUND

6"

SURVEYOR REFERENCE

CAP

.~

CONCRETE MONUMENT (PERIMETER CORNERS)

3/4" '" MIN. IRON PINWI SQ. CUT TOP SET FLUSH

WI TOP OF CONCRETE

.<1 0

CONCRETE MONUMENT (UNPA VED STREETS)

CONCRETE MONUM ENT DETAIL

DRAWN BY: M.J. WIDMAN, P.S. APPROVED BY: DA BRUNKHORST, P.E., R.S.

REVISIONSOTTAWA COUNTY ENGINEER' S OFFICE I-------r-------t

315 MADISON STREET , ROOM 106 PORT CLINT ON, OH 43452

(419) 734-6777

CM-1SCALE' 2" = "

3-1/4" 0 DOMED BRASS OR AL UM INUM REFERENCE DISK

(FLARED OR PINNED)

NOTES:

1. BENCHMARK MONUMENTS ARE TO BE CAST IN PLACE TO ASSIST IN MINIMIZING ANY SETTLEMENT

2. REFERENCE DISKS CAN EITHER HAVE A FLARED STEM, OR A HORIZONTAL ANCHO R PIN PLACED THROUGHT T HE STEM.

3-114"0 DOMED BRASS OR ALUMINUM REFERENCE DISK

5/8"

6"

BENCHMARK MO UMENT DETAIL

DRAWN BY: M.J. WID MAN, P.S. APPROVED BY: D.A. BRUNKHORST, P.E., R.S.

REV ISIONS onAWA COU NTY ENGIN EER'S OFFICE 315 MAD ISON STRE ET, ROOM 106

PORT CLINTO N, OH 43452 (419) 734-6777 BENCHMARK MONUMENT

SCALE : 2" = l' BM-1

A

I

I I

I I

I I

A

I I

I I

I I

I 20 ' I

60'

PLAN

R/ 'vi

1----- --- - - 63 ' R/ 'vi ( Min)----- - ------1-1

E/ P

1--------43 ' ( M i n)---------+--------I~ 20 '

PROF ILE

SECTION A- A DIMENSIO NS ARE FOR RESIDENTIAL CUL -DE - SACS NOT USI NG CURB AND GUTTER

NOTE HA H

RESIDENTIAL CUL - DE- SAC MINIMUM E/ P RADIUS IS 43 ' E/ P COMMERCIAL /INDUSTRIAL CUL-DE-SAC MINIM UM E/ P RADIUS I S 60' E/P

NOTE HE" RESI DENTIAL CUL -DE - SAC MI NIMUM R/'vi RADIUS I S 63 ' COMMERCI AL / IN DUSTRIAL CUL-D E-SAC MINIMUM R/ 'vi RADI US IS 8 0'

CUL-DE-SAC DETAIL

DRAWN BY: J.D. BARNES, E.!., S.I APPROVED BY: DA BRUNKHORST, P.E., R.S.

REVISIONS o nAWA COUNTY ENGINEER'S OFFICE f--- ...,-- --I

315 MADISON STREET, ROOM 106 PORT CLINTON , OH 43452

(419) 734-6777

SCALE: NTS CDS- 1