department of public works · •mob & demob for stabilization (duration, phasing) •estimate...

Department of Public Works

Stormwater NPDES Compliance

Designer Training

September 3, 2020

Presenters

Gail Boydston

MS4 NPDES Coordinator

Gail.Boydston@indy.gov

Kathy Allen

DPW Contractor

Kathy.Allen@indy.gov

• Legal Requirements

• Importance

• Construction

• Post-Construction

• Lessons Learned

• Questions

Agenda

• MS4 NPDES Phase I Permit

• City Stormwater Manual

• Rule 5

Legal Requirements

Importance

Water Quality

• Recreation

• Animals & Plants

• Drinking Water

• Community Pride

• Economics

Construction

• INDOT RSP

• IDEM Rule 5

• Utility Coordination

• Inlet Protection

• Culverts

• Bridges

INDOT RSP 205-R-706

• Projects with 205 pay items

• Unit prices for E&SC

• Provide only 2 pay items

Construction

INDOT RSP 205-R-706Use unit prices in the RSP to build the

budget

Storm Water Management Budget items:

• Temporary silt fence (lft)

• Temporary inlet protection (each)

• #2 stone for construction entrance (ton)

• Riprap check dams (each)

Construction

INDOT RSP 205-R-706Storm Water Management Budget items:

• Manufactured surface protection product (erosion control blanket)

• Temporary seed & mulch• Mob & Demob for stabilization (duration,

phasing)• Estimate CYD sediment removal based on

duration of the project, # measures• Measurement for the installation - common

excavation (205.11)

Construction

INDOT RSP 205-R-706Storm Water Quality Control Plan (SWQCP)

Preparation and Implementation

• Prepared by contractor

• In tandem with the SWPPP or E&SC plan

• Contractors bid on this item

• For cost estimate:

– SWQCP preparation (preparer: PE & CPESC)

– Weekly and Post Rain event inspections

Construction

INDOT RSP 205-R-706Concrete Washout

• RSP includes washout for items such as mortar,

grout, saw cutting, dewatering contaminated

from concrete pours, hydrodemolition, and

similar operations.

• Note and/or detail on plans

Construction

IDEM Rule 5

• Construction General Permit

• 1+ Acre Disturbance

• IDEM SWPPP Guidance

– A: Project Information (23)

– B: Construction (15)

– C: Post-Construction (5)

• E&SC Plan for < Acre Disturbance

Construction

IDEM Rule 5

• SWCD reviews SWPPPs

– 30 days

– Time for comments

– marioncountyswcd@iaswcd.org

Construction

IDEM Rule 5

• NOI electronic submittal

– Required for DPW projects

– IDEM ePortal

– Must have DPW PM email

– DPW PM must be a city employee

– Automatic emails sent to DPW PM

• Public Notice

Construction

Utility Coordination Process

• Process & documents on website

• Project Stakeholder List

– Download new list EACH time

• NPDES review is EPA commitment

• Level 1 or Level 2 project

Construction

Inlet Protection

• Time for water to pool and sediment to drop

– Doesn’t impede active traffic

– Must have overflow

– Maintainable (Without dropping sediment into

the storm sewer)

• Downslope from project area

Construction

Culverts

• Direct Impact to Streams

• Pump arounds

– Coffer dams

• non-erodible

• entire project

• elevation

– Dewatering vs. pump around

Construction

Bridges

• Direct Impact to Streams

• Constructability & Sequencing

– Access drives

– Scour protection around piers

– Dewatering

– Demolition

Construction

• When are BMP’s Required

• Changes to Stormwater Manual

• O&M Considerations

• O&M Manuals

Post-Construction

When are BMP’s Required

• 1/2 acre+ disturbance

– Milling is not disturbance

– FDR is disturbance

• MS4 NPDES permit requirement

• When not practicable

– Consult with DPW PM

– Document decision

Post-Construction

Changes to Stormwater Manual

• Comprehensive update

• Incorporation of many INDOT standards

• Chapter 700

– no inlet filters

• Effective 2021 (anticipated)

– After DPW Board Adoption

– Q1 or Q2

Post-Construction

O&M Considerations• Operations on Project Stakeholder List

• Inlet filters and sumps high maintenance

• Cleanout ports 8+”

• Avoid travel lanes

• Biofiltration requires a contract

• Permeable pavers as last resort– Not approved BMP

– Consider loading (tree cover/type, erosion, mulched beds)

Post-Construction

O&M Manuals

• Quality and quantity features

• Locate on a plan

• Inspection and Maintenance frequency

• Include a Checklist (new Chapter 100)

• Submit with plans & at closeout with

record drawings

Post-Construction

• Utility Coordination

– Use new list

– Resend for ‘shelved’ projects

• SW Budget

• O&M Manuals Required

Lessons Learned

• Structure access size

– Size accordingly

– 22” much lighter than 27 7/8”

• ID on lids for Manufactured BMPs

• Specify topsoil for detention basin slopes

• Access drives for basins

Lessons Learned

Questions?

Gail Boydston

Gail.Boydston@indy.gov

Kathy Allen

Kathy.Allen@indy.gov