Inspection and Maintenance Program Development for the City of 

Philadelphia’s Green Stormwater Infrastructure

Chris Bergerson, PWDBethany Boisvert, AKRF

$1.67 billion

$345 million

Green Stormwater Infrastructure

Adaptive Management

Traditional Infrastructure

GREEN CITY, CLEAN WATERS

$420 million              

The City of Philadelphia’s Program for Combined Sewer Overflow Control$2.4 Billion Investment over the next 25 years

Ramping UP for Implementation

• A 5‐year ramp‐up period is planned to increase PWD production of GSI

• Ramp‐up gradually increases GA target to a level that can be continued for remaining 20 years of program

• First 5 years used to ramp up to an average of 290 GA per year to meet 25 year goal of 6560 GA

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Annual Cummulative

Green Infrastructure Maintenance Manual

Delivery: June 1, 2014

Metric: Greened Acres

Defining maintenance activities, frequency and efficiencies for long‐term success of each type of 

green stormwater infrastructure

www.phillywatersheds.org

SMPs – 2010 Program

SMPs – 2011 Program

Program Components

•Inspection•Maintenance•Reporting•Site‐specific protocols

Inspection and Maintenance Program

Inspections–Condition Assessment

Inspections–Issue Identification

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3/23/2010 5/12/2010 7/1/2010 8/20/2010 10/9/2010 11/28/2010

Volume (cf)

Sinkhole Void Volume

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le filled 

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le filled 

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SITE 10: PALMERInspection

Date:_____________________________

Measurements

Feature Structure Type Measurement March April May June July August Sept October November

10_02 Street inlet 1 TOG_TOW (in) 40.8(NW inner) TOG_TOS (in) 67.9

10_03 Observation well 1 TOG_TOW (in) 57.5(NW) TOG_TOS (in) 62.4

10_11 Street inlet 2 TOG_TOW (in) 47.6(SE) TOG_TOS (in) 79.5

10_12 Observation well 2 TOG_TOW (in) 64.1(SE) TOG_TOS (in) 66.1

10_17 Steet inlet 3 TOG_TOW (in) 57.1(NW outer) TOG_TOS (in) 85.7

Inspections–Monitoring

•Sediment accumulation•Water levels•Settling / sinkhole

Inspections–Monitoring

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3/23/2010 5/12/2010 7/1/2010 8/20/2010 10/9/2010 11/28/2010

Distance from Top of Grate (inches)

Structure Bottom

Invert

Sediment Level

Inlet cleaned

Sediment Levels within Inlet

Inspections—Photo Documentation

2010

2011

April

March

August

May August

Number of Crew Members (including foreperson): Start Time:

Crew Organization: End Time:

PM FP LB1 LB2 LB3 MS Other Item Quantity Units Item Quantity Units

Site: ____________________

Date: ____________________

TaskLabor Effort Materials (Added or Removed) Materials (Added or Removed)

TRASH REMOVAL

SEDIMENT REMOVAL

ORGANIC MATERIAL (LEAVES/WOOD) REMOVAL

INVASIVE/NON‐TARGET PLANT REMOVAL ‐ HAND

INVASIVE/NON‐TARGET PLANT REMOVAL ‐ MECHANICAL

INVASIVE/NON‐TARGET PLANT REMOVAL ‐ HERBICIDE

PRUNING

Inspections–Maintenance Tracking

•Tasks performed•Labor effort•Labor skill•Materials

Maintenance

•Trash and sediment removal•Weeding, pruning, etc.•Structural repairs•Erosion control•Reseeding•Watering

Labor 77%

Materials 23%

Maintenance CostsLabor and Materials as Percent of Annual Maintenance Cost

Percent of Annual Maintenance Cost by Task

3% 3%4%

4%

7%

36%

43%

Erosion Control

Mulching/top dressing

Design/Installation Enhancement

Oversight

Minor structural repairs

Cleaning

Vegetation care

1. Planting2. Watering3. Weeding (invasive or non‐target)4. String trimming

1. Sediment/debris removal2. Trash removal3. Deteriorated porous pavement removal4. Organic material removal

Maintenance Costs

Percent of Annual Maintenance Cost by Site

Maintenance Costs

1% 2% 2% 2%6%

16%

16%19%

36%

Clark Park

Jefferson Square

Liberty Lands

Herron Playground

West Mill Creek

Waterview Recreation Center

Cliveden Park

47th and Grays Ferry

Columbus Square

•Trash•Pollution•Vandalism•Car accidents•Size constraints•Heat and exposure

Challenges in the Urban Environment

•Routine maintenance tasks•Maintenance standards•Required equipment•Crew size and skill•Frequency of visits•Frequency of tasks•Responsible party

Site‐Specific Protocols

•Maintenance friendly design•Enhanced pretreatment•Proven performers plant lists•Frequency of maintenance•Material reuse•Prevention of theft/vandalism•Product testing

Feedback for Design and Maintenance

•Improving logistics•Reducing labor effort•Green infrastructure crews•Reusing materials on site•Standardizing materials•Green infrastructure awareness•Improved construction oversight•Increasing maintenance independence

Scaling Up

Montgomery Ave. Tree TrenchHurricane Irene

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Date & Time

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Montgomery Ave. Tree TrenchTropical Storm Lee

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Date & Time

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Palmer St. Tree TrenchHurricane Irene

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Date & Time

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Water Depth SWT-B4 (upslope) Water Depth SWT-A4 (downslope)

Palmer St. Tree TrenchTropical Storm Lee

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Date & Time

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Water Depth SWT-B4 (upslope) Water Depth SWT-A4 (downslope)

Bethany BoisvertAKRF, Inc.Environmental, Planning, and Engineering Consultants

THANK YOUhttp://www.phillywatersheds.org

Chris BergersonPhiladelphia Water DepartmentOffice of Watersheds