green city, clean waters · 1/24/2017 · • 485 stormwater tree trenches • 73 stormwater...

Green City, Clean Waters


Accepted and endorsed by our partners:

• Regulators: PA DEP and EPA

• Non-Profits: NRDC, Sierra Club, Clean Water Action, The Nature Conservancy, Trust for Public Lands

Memorialized by:

• 2011 Consent Order and Agreement (COA) with the PA Department of Environmental Protection

• 2012 Landmark Partnership Agreement and Administrative Order for Compliance on Consent with the US Environmental Protection Agency

Signing of Green City, Clean Waters Agreement

Consent Order & Agreement

• COA requires that the City construct and place into operation the controls necessary to achieve the elimination of the mass of pollutants that would otherwise be removed by the capture of 85% by volume of the combined sewage collected in the Combined Sewer System during precipitation events on a system-wide annual average basis.

Water Quality Based Effluent Limit (WQBEL)

Metric UnitsBaseline

value

Cumulative amount as of Year 5 (2016)

Cumulative amount as of

Year 10 (2021)


Year 15 (2026)


Year 20 (2031)


Year 25 (2036)

NE / SW / SE WPCP upgrade: Design

percent complete

0 TBD June 2013 TBD June 2013 TBD June 2013 100% 100%

NE / SW / SE WPCP upgrade: Construction

percent complete

0 TBD June 2013 TBD June 2013 TBD June 2013 100% 100%

Miles of interceptor lined

Miles 0 2 6 14.5 14.5 14.5

Overflow Reduction Volume

million gallons per

year0 600 2,044 3,619 5,985 7,960

Equivalent Mass Capture (TSS)

Percent 62% Report value Report value Report value Report value 85%

Equivalent Mass Capture (BOD)

Percent 62% Report value Report value Report value Report value 85%

Equivalent Mass Capture (Fecal

Coliform)Percent 62% Report value Report value Report value Report value 85%

Total Greened AcresGreened

Acres0 744 2,148 3,812 6,424 9,564

COA DeliverablesDeliverable Name Deliverable Date

Implementation and Adaptive Management Plan December 1, 2011

Green Infrastructure Maintenance Manual Development Process Plan

June 1, 2012

Comprehensive Monitoring Plan December 1, 2012

Facility Concept Plan for NE WPCP June 1, 2013

Facility Concept Plan for SE WPCP June 1, 2013

Facility Concept Plan for SW WPCP June 1, 2013

Updated Nine Minimum Controls Report June 1, 2013

Tributary Water Quality Model – Bacteria June 1, 2013

Tributary Water Quality Model - Dissolved Oxygen June 1, 2014

Green Infrastructure Maintenance Manual - First Edition June 1, 2014

Tidal Waters Water Quality Model - Bacteria June 1, 2015

Tidal Waters Water Quality Model - Dissolved Oxygen June 1, 2015

Metric Units

Cumulative amount

as of Year 25

(2036)

NE / SW / SE WPCP

upgrade: Design &

Construction

Percent complete 100%

Miles of interceptor lined Miles 14.5

Overflow Reduction

Volume

Million Gallons per

year7,960

Equivalent Mass Capture

TSS / BOD / Fecal

Coliform

Percent 85%

Total Greened Acres Greened Acres 9,564

Water Quality Based Effluent Limit

Green Infrastructure

Bureau of Laboratory Science planters Columbus Square planters

George W. Nebinger School rain garden Kemble Park rain garden

Greened Acre = IC * Wd Impervious

CoverRunoff Depth

Opportunities & Barriers

Year Greened Acres Square Miles% Impervious

cover managed

5 750 1 3%

10 2,100 3 8%

15 3,800 6 14%

20 6,400 10 23%

25 9,600 15 34%

25-Year Implementation of Green City, Clean Waters

Green Stormwater Infrastructure Requirements

Assumes GSI storage equivalent to 1.0 inch of runoff

Southeast Philadelphia (10th & Moyamensing), photo by Andrew Dobshinsky

Pathway to Green

Approach: Public Opportunities

Approach: Projects Initiated

Stormwater Tree Trench

Stormwater Bump-out

Stormwater Planter

Permeable Pavement

Rain Garden

• GSI Planning Guidelines• GSI Design Process Workflow Packet• GSI Design Requirements & Guidelines• GSI Drawing Requirements Packet

– GSI CAD Standards• GSI Standard Details• GSI Project Implementation Workflows• Landscape Guidebook

www.phillywatersheds.org/gsi_design_resources

Planning and Design | Key Resources

http://www.phillywatersheds.org/gsi_design_resources

Streets

• Traffic calming

• Pedestrian crossing

• Neighborhood re-investment and revitalization

• Increase in property value

Streets

• green infrastructure on health and safety outcomes from 2000 to 2011 in Philadelphia found…..

• Consistent and statistically significant reductions in narcotics-possession (18-27% less)

• Narcotics manufacture was also significantly reduced

Streets

• Urban tree cover influence on crime

• 10% increase in tree canopy was associated with a roughly 12% decrease in crime

Streets

• Areas that have the most trees along the streets also had fewer prescriptions for antidepressants


• Leveraged capital investment in neighborhood anchors

• Public spaces with high pedestrian traffic

• Engagement with local communities and venues

Parks

Hawthorne Park

Parks

• …people reported less mental distress and higher life satisfaction when they were living in greener areas

Parks

Womrath Park

• Life satisfaction increased by 2% and psychological distress decreased by 4%

Parks

Kemble Park

• As green space increased within a 2.5-mile radius of where they lived, overall well-being increased proportionally.

Campuses

• Large land type with single ownership

• Opportunities for students and professors to perform research that will inform later phases of GCCW

• Highly trafficked pedestrian areas are ideal for program tours and marketing

• Coordination for projects in adjacent communities

Schools• …richer and poorer areas saw similar increases in scores with increasing vegetation (NVDI).

• …“that surrounding greenness has approximately equal effects on student academic performance regardless of financial status or gender.”

Schools

Photo : Jenna Stamm , courtesy of The Trust for Public Land

Schools

• …consistent and systematically positive relationships between nature exposure and student performance

Schools

• Views with greater quantities of trees and shrubs from cafeteria as well as classroom windows are positively associated with :

• standardized test scores, graduation rates, and percentages of students planning to attend a four-year college

Schools

• …linked views of nature with restoration from mental fatigue and stress reduction

GSI on Streets, Schools, Parks, and other Public Property

PWD has completed or is in the process of designing:• 485 Stormwater Tree Trenches• 73 Stormwater Planters• 49 Stormwater Bump-outs• 96 Rain Gardens• 12 Stormwater Basins• 141 Infiltration/Storage

Trenches• 31 Porous Paving Projects• 28 Swales• 2 Stormwater Wetlands• 33 Downspout Planters• 15 Other Projects

137 sites, 179.7 acres

Private Investment: Development Regulations

New Development & Redevelopment with earth disturbance exceeding 15,000 square feet:

• Water Quality; Channel Protection; Flood Control • Meets the definition of a greened acre and manages the first inch

of runoff• Opportunity to leverage private development

Sites: Philadelphia Zoo, Shoemaker Green (Penn Campus), Paseo Verde (APM), Pashall Village (affordable housing), Radian (40th and Walnut)Photo Credits: WRT and Paul Rider

Local Business:PWD Storm water pioneer

Development:Granary Green Roof

Private Investment: Development Regulations

Stormwater Regulation Enhancements

• 2015 stormwater regulation and manual updates

• Better align to collection system response and system performance goals

• Maximize management using vegetated practices

• Website improvements

• More flexibility to the development community

Parcel Based Billing for Stormwater

Gross Area Charge = $ 0.69 / 500 sq ft /month

Impervious Cover = $ 4.75 / 500 sq ft / month

www.phillystormwater.org

Incentivized Retrofits• Up to 80% credit for the management of 1” of stormwater

• 1 acre parcel pays $500/mo, $5600/yr for stormwater / Managing 1” over property lowers bill to $100/mo, $1100/yr

Rain Garden

Porous Pavement

Sub-surface Detention PondGreen Roof

Surface Detention Pond

Stormwater Wetland

68.7 Greened Acres$3.4 million SMIP GrantCost to PWD per GA: $49,000SW Fee reduced:

$250k/yr to $50k/yr

Cardone

Greene Street Friends School

Incentivized Retrofits

LaSalle Campus

MINK/Popi’s Diner


Dependable DistributionWharton Street Lofts

GSI on Private Development and Redevelopment Projects

+GSI Through Incentivized Retrofits

266 projects, 423.4 acres


Philadelphia has many small spaces and tight yards.

This space belongs to two different properties!

If we can manage stormwater here…Separate

Properties

You can do it

anywhere!

GSI on Streets, Schools, Parks, and other Public Property

+

GSI on Private Development and Redevelopment Projects

+

GSI Through Incentivized Retrofits


266 projects, 423.4 acres


SUCCESS!

Metric UnitsBase

Line Value

First 5-Year

WQBEL Target

Cumulative as of

Year 5

(2016)

Miles of Interceptor

LinedMiles 0 2 7.5

Overflow Reduction

Volume

Million Gallons Per Year 0 600 1,710

Equivalent Mass

Capture (TSS)Percent 62% Report value 70.5%

Equivalent Mass

Capture (BOD)Percent 62% Report value 88.9%

Equivalent Mass

Capture (Fecal

Coliform)

Percent 62% Report value 72.0%

Total Greened Acres Greened Acres 0 744 837.7

We have not only achieved out year 5 targets, we have exceeded them!

Public Retrofits

60 Work Numbers

• Average Project Size…………..............2.9 GAs• Average Depth Managed.................1.4 inches• Average Drainage Area....................1.9 acres

DESIGNDesign Started to Design Complete

CONSTRUCTIONDesign Complete to Construction Complete

15.0 months 7.2% GA Increase 16.3 months 2.7% GA Decrease

TOTAL TIMING 2.6 years

171.4 GAs

Renew/Replace

10 Work Numbers


DESIGNDesign Started to Design Complete

CONSTRUCTIONDesign Complete to Construction Complete

48.8 months 19% GA Increase 26.2 months


8.3 GAs

(Re)Development Regulations

266 Projects


CONCEPTProject Initiation - Technical Submittal

5.1 months 3.4 months


DESIGNTechnical Submittal - Construction Started

CONSTRUCTIONConstruction Started - Verified

18.0 months

423.4 GAs


38 Projects


CONCEPTAwarded - Technical Submittal

8.5 months 9.4 months

TOTAL TIMINGSMIP 24.6 monthsGARP 16.4 months

DESIGNTechnical Submittal - Construction Started

CONSTRUCTIONConstruction Started - Verified

6.7 monthsSMIP

GARP 1.0 month 4.0 months 11.4 months

234.6 GAs

5 Year GSI Costs – Design, Construction, Construction Mgmt (as of June 2016)

(Re)Development Regulations Greened Acres: $10M

• Spend approximately $2M/year in Operating costs to manage all aspects of the Stormwater Regulations program (Plan Review Staff, Inspections and Enforcement, Website and Data Management )

Public Retrofit Greened Acres: approx. $40M / $225k per GA

• $30.2M for Compensated Construction

• $5.5M for Professional Service Costs (Design and Construction Mgmt)

• $4M PWD Labor Costs (Design and Construction Mgmt)

Incentivized Retrofit Greened Acres: $16.5+M

• $10.5 SMIP-related Design, Construction and Construction Mgmt

• $5M GARP-related Design, Construction and Construction Management

• $1+M to date for PWD Labor (Design Reviews and Construction Inspections)

5 Year Costs – Maintenance

Public Retrofit Greened Acres:

• Maintenance costs calculated as a percentage of total capital costs

• For projects with Complete Capital Costs – closed projects where we had full accounting of costs

3.9% - Sample Size 41 projects

• Projected costs when adding projects still in Construction or Design


• Projected costs for projects with anticipated Maintenance dates in FY18


• PWD Labor force to Manage all aspects of Maintenance program - $1M/yr

The greater the challenge, the greater the opportunity, the greater the outcome.

Years 6-10 Look Ahead

Metric Units WQBEL Target

Miles of interceptor lined miles 6

Overflow Reduction Volume million gallons per year 2,044


(TSS)percent Report value


(BOD)percent Report value


(Fecal Coliform)percent Report value

Total Greened Acres Greened Acres 2,148

Greened Acre Projections• (Re)Development Regulations Greened Acres:

– There are 172 projects in the (Re)Development queue, ranging from technically approved (pending construction) to constructed but pending verification.

– PWD will attempt to identify opportunities to work with the property owners and engineers to maximize stormwater management potential.

• Public Retrofit Greened Acres:– PWD already has 276 projects in progress ranging from “in design” to “in

construction”. – PWD has observed that public retrofit projects take on average 2.6 years

from the point that they initiate design through construction completion. This has set the minimum pace for PWD to move projects through the implementation pipeline

• Incentivized Retrofit Greened Acres:– As of June 2016 there were 79 GAs worth of awarded projects currently in

progress; more awarded since then.– PWD plans on budgeting a combined $15 million per year to support both

SMIP and GARP grants through 2021

Planning

Planning | Large Area Disconnection

Analysis for Large Area Disconnection (LAD) is performed when there are open space areas that appear to provide the opportunity to manage runoff from areas beyond those immediately adjacent to the site.

Design

Topic Current Design Requirement/Guideline

Target depth of runoff managed 1.5”, maximum of 2”Design drainage areas Directly connected impervious areas (DCIA)

Sizing methodology Static storageInfiltration Rate > 0.25”/hr

Drain Down Time 72 hoursSlow-Release Rate 0.05 cfs/acre DCIA

Minimum Orifice Size 0.5”Underdrains Always included, (safe guard for future clogging)

Loading Ratio Target 10:1, higher rates permitted on case by case basisBuilding Setback 10 feet

Inlet Capacity Rational method, using 1 yr storm intensityInlet Selection PWD Standard Inlets preferredLandscaping Species selection from a recommended plant list

Reporting Design Report (as per GreenIT specifications)

MonitoringMinimum one observation well per system (not applicable

to rain gardens/planters without stone)Drawing Requirements OOW GSI CAD StandardsReview Requirements Based on PWD & City Standards

Submission Requirements Based on PWD Standards

Design: Requirements and/or Constraints

Construction

Construction

• Soil Compaction

• Erosion and Sediment Controls

• Prime/Sub Supervision and Communication

• Warranties

• Material availability and integrity

• Landscaping

• Grading

• Small tolerances

• Punchlist items

Maintenance

Inspection:•Visual/photographic•Record condition of vegetative and structural features•Measure sediment and water levels

Maintenance:•Trash and sediment removal•Weeding, pruning, etc.•New product testing•Structural repairs•Erosion control•Reseeding / Watering

Reporting:•Labor effort and materials required to maintain each site

Creating Standards and Protocols:•Required tools and Crew Size•Frequency of visits•Responsible party

Maintenance


Diversity: Resources and Workforce

Professional Services Contracts

City Workforce

Adoption Programs

Requirements ContractsSpecial Service Districts

PowerCorpsPHL

Equipment, Materials, Supplies Contracts

Business Improvement Districts

PowerCorpsPHL

Surface Maintenance

Relational Asset Management

SMP

Component

Attribute

Relational Asset

Management &Maintenance Maps

CityWorks: GSI Entity Group

Damaged Infiltration Trench @ 12th St & Tasker

Monitoring

• GSI project sites being actively monitored

• Pressure transducers in monitoring wells

• Water level logging stations (Tree Trench, Porous Pavement, Infiltration Trench

• Barometric Pressure Stations

• Groundwater Wells

• Smart Sensor Technologies

• Arduino microcontrollers

• Wireless data transmission

• “Hackathons” – civic minded programmers

Monitoring• Goals:

• Evaluation of GSI performance

• Inform future designs

• Inform Maintenance

GSI Monitoring Philosophy

• Focus on water quantity

• Focus on individual system performance

• Focus on regulatory metric (“Greened Acre”)

– 1” of runoff from 1 acre impervious cover

Major Monitoring Methods

• Continuous water level monitoring

– Measure the effects of many rain events

– “How does this system perform in general?”

– “How has this system’s performance changed?”

• Simulated runoff testing

– Simulate a rain event by manually applying flow

– “How does this system respond to this storm?”

Monitored SMPs, by type

Typical Tree Trench: cross section

1. Drainage Area

2. Stage-storage Curve

3. Orifice Size &

Height

4. Pre-construction Infiltration Rate

| DATA COLLECTION

PHILADELPHIA WATER | ANALYSIS METHODS

Water Budget Method

| ANALYSIS METHODS

Pilot Program

“Information from pilot projects will be collected to develop a cost effective GSI program by testing a variety of projects and evaluating them for a number of factors, including:

• Ability to meet performance requirements

• Ease of implementation for on-street and off-street settings

• Cost-effectiveness of various physical conditions

• Efficiency of various systems

• Effectiveness of various materials

• Ease of maintenance GSI ”

Pilot Program Final Report

DATA

SYSTEM

VARIABLES

STATISTICAL

ANALYSIS

PilotDB

| ANALYSIS TOOLS

Pre- and Post-Construction Relationship: Infiltration Rate

| RESULTS

CDF: Inches of rainfall for every system-event

Event Designed Overflow Actual Overflow

Rai

nfal

l (in

ches

)

| RESULTS

About 5,000 events, 500 of which are designed to overflow, and about 20 that actually overflow

Water Budget Analysis

• Runoff Volume

• Managed Volume

• Unmanaged Volume

Water Balance Columbus Square Planter Trench*

*12/11/2012- 12/14/2015 1,099 days

107 inches of rainfall

| RESULTS

Volu

me

(cf)

Runoff Designed Performance

Measured Performance

Program Performance/Pilot Results Summary

• The performance monitoring of GSI (results of infiltration rate, storage use, and drain down duration analyses together) makes a strong case that PWD’s GSI systems are performing better than predicted using current engineering design assumptions• The systems overflow less often than predicted• The systems experience higher infiltration rates and faster drain

down times than predicted• The systems have more excess storage capacity available than

predicted over a range of events• Over a range of wet weather event sizes, the fraction of storage capacity

utilized is consistently less than predicted by design assumptions, providing further evidence of over-performance.

– For 15 systems where this data was analyzed, the average maximum portion of available storage used is less than 53% during storms less than 3.0 inches of rainfall depth, and approximately 60% for storms greater than 3.0 inches of rainfall depth

• Approximately 95% of storms from 2012 to 2015 (and PWD’s “typical year” used in wet weather planning) were 2.0 inches depth or less, with 12 storms in the monitoring period above 2.0 inches depth.

– results indicate that systems are regularly managing storms in excess of 3.0 inches with significant storage capacity remaining unused

Piloting, Research, and Innovation

• Academic Research Partnerships

– EPA STAR Grants

– Villanova University

– Drexel University

• Pilot Projects – New Materials, Technologies, Approaches

– Bioretention soil mix

– Drainage wells

• Data Management, Visualization and Analysis Tools

Where we’re going next…

• Innovation!– Cost reduction and efficiencies particularly within Design, Construction,

Maintenance and Monitoring elements

– Standardizing best practices

– Expanding programs and incentives for private green infrastructure activities – Alternative Project Delivery Methods

– National GSI Practitioners Information Exchange

• Continue to generate Green Jobs

• Monitoring performance at scale

• Grow community partnerships to engage in planning and to address local needs (ReBuild)

• Integrate CSO controls with flooding and climate change


www.phillywatersheds.orgwww.phila.gov/water

http://www.phillywatersheds.org/

http://www.phila.gov/water

green city, clean waters · 1/24/2017 · • 485 stormwater tree trenches • 73 stormwater...

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