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Green Streets Implementationand Green Infrastructure Maintenance

ANDREW POTTS, P.E., LEED AP, CPESC

andrew.potts@ch2m.com

MAY 1, 2014

Overview

Green streets case studiesGreen infrastructure maintenanceGreen Infrastructure asset managementQuestions

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They typically represent 25-35% of the total impervious area

Runoff control opportunities often exist within the right-of-way, even in confined urban areas (with utilities, etc.)

Align well with urban greening efforts and goals; good for business, property values, etc., desired by the public

High visibility and educational opportunities

Can be cost effectively implemented by “piggybacking” with planned utility or other improvements

Permit compliance

WHY INVEST IN GREEN STREETS?

GREEN STREET COSTS/AREA MANAGED

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CITY OF LANCASTER GREEN INFRASTRUCTURE

PROGRAM

GREEN STREETS & ALLEYS

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Green Street Focus

Pavement Management Focus

PAVEMENT ASSESSMENT

Lowest Overall Green Street Cost

Lowest Overall Green Street Cost

PRIORITIZATION CRITERIA YIELDED MOST COST-EFFECTIVE GREEN STREETS OPPORTUNITIES

Pavement Condition

Street Slope &

Other Factors

Watershed / Basin Priority

ADA Priority

Road Type- Width- Traffic (“Functional Class”)- Ownership (City, State, private alleys)

Tree CanopyFlooding locationsOverhead WiresSidewalk ConditionInlet Condition

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ALLEY 148 GREENED FOR 10% ADDITIONAL COST, CAPTURES 200,000 GALLONS PER YEAR, IMPROVES NEIGHBORHOOD

Conventional reconstruction (8-inch reinforced concrete) ~$20.30/SF

Green alley retrofit (permeable pavers with infiltration trench) ~$22.40/SF

Before (July 2011) After (February 2012)

Lancaster Brewing Public Private Partnership

Rendering by McCormick Taylor

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USING TRAFFIC SAFETY AND TRANSPORTATION FUNDING TO REDUCE ACCIDENTS AND RUNOFF

5 MPH reduction in average traffic speed

Built with Transportation and GI Grant funds

Helps local business

INTEGRATING TRAFFIC IMPROVEMENTS IMPROVES SAFETY, LOCAL BUSINESS, AND BRINGS NEW FUNDING SOURCES

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NEW OUTDOOR SEATING WITH POROUS PAVERS

HARRISON STREET – ONONDAGA COUNTY (SYRACUSE), NY

BEFORE: Stormwater enters catch basins and is directly connected to sewer

AFTER: Stormwater is diverted to Green Streets and only overflows to sewer when necessary

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Design Considerations• Use of sand-based structural soil to enhance rooting volume• Bike boulevard• Traffic calming• Porous paver parking lanes• Work around and with utilities• Bioswales• New sidewalks (beyond project limits)

GI IMPLEMENTATION AT THE WATER STREET GATEWAY ACHIEVES MULTIPLE COMPLETE STREET BENEFITS

Limiting Site Conditions• Utilities! (adjacent to old Erie Canal)• Old canal remnants, SHPO issues, old rails, etc•Mid-street pedestrian crossing• Snow plow considerations• Turning radii for tractor trailers• High visibility

So… when should I start thinking about maintenance?

At the start of design!

(if not earlier)

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Effective Maintenance Starts At Design

Consider maintenance requirements when selecting GI types

Design for minimal maintenance where limited resources are available or when located on private property GI types that require greater or specialized maintenance might be better suited for

sites with rigorous ongoing maintenance, such as schools, commercial areas, urban plazas and public parks

Be aware of site constraints that make maintenance difficult and avoid locating GI in these areas (e.g., slopes)

Design pre-treatment that ensures long-term functionality

Design for ease of inspection and maintenance, provide access

Select appropriate plants for the application (e.g., salt & drought tolerant)

Include contingencies (e.g., backup drains, overflow structures, and underdrains)

Maintenance: From Gray to Green

Typically relies less on heavy equipment and confined entry and more on hand work, less “out of site”

Vegetation establishment and maintenance critical

Routine maintenance of porous materials

Routine maintenance of pretreatment devices (e.g., inlet filters)

Required inspections to meet regulatory requirements (MS4)

Highly visible systems and structures require routine maintenance for aesthetics and public perception

Often overlaps with maintenance that is already taking place!

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General GI O & M Practices and Cost

GI Type Required Routine Maintenance Annual Frequency 

Annual Cost ($)*

Porous Pavements VacuumingInspect & Clean Structures

2 0.15‐$0.25 per SF

Bioretention/Rain Gardens

Inspect & Clean StructuresEstablishment Watering (1st year)Weeding, Pruning, MulchingErosion Control

2 $0.30‐$1.50per SF

Vegetated Roof Inspect & Clean StructuresReplace VegetationWeeding, Pruning, Mulching (optional)

2 $0.10‐$0.30 per SF

Tree Trenches Inspect & Clean StructuresEstablishment Watering (1st year)Weeding, Pruning, Mulching

2 $15 Each Tree

Cisterns Inspect & Clean Structure & Filters 2 $100 per 1000 gal

*Total Estimated Cost Not Accounting for Overlap with Existing O&M

Barriers to Effective GI MaintenanceBudgeting for the Operations and Maintenance for

Green Infrastructure Need for Training and Certification in Green

Infrastructure Operations and MaintenanceDeveloping Enforcement and Inspection ProceduresPoor Public Awareness

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Paying for Green Infrastructure Maintenance

Stormwater Utilities to fund GI O & M Provide a stable, dedicated revenue source Equitable approach that bases fees on impact Incentivize private investment through credit/rebate programs

that reduce fees by reducing impact

Alternative Financing Beneficiary Opportunity Fund Public-Private Partnerships Infrastructure Improvement Districts Clean Water Funds (taxes, sewer fees, etc.)

Training and Certification in Green Infrastructure Operations and Maintenance

Develop Maintenance Standards & Guidelines

Establish Maintenance Training and Certification Programs E.g., NC State BMP Maintenance Certification Program

(required in 10 cities/counties in North Carolina)

Improve Collaboration with Community Groups

Workforce development = Green Jobs

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Linking Green Infrastructure Maintenance to Green Jobs

Highly visible vegetative GI practices make them more likely to be maintained

Requires workforce with new skills

Can create long term permanent jobs

Specially trained professionals for inspections

Opportunity to create entry level positions to disadvantaged youth

So I’ve just built 150 Green Infrastructure projects… how do I maintain them all?

Asset Management

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Example of Institutionalized Maintenance for a Large-Scale GI Program: Onondaga County (Syracuse), NY

Large‐scale GI Program (consent decree driven)

Onondaga Lake – once one of the most polluted lakes in the US

Goal is to significantly reduce lake bacteria and nutrients; specifically to: Green 470 acres 

Reduce 247 MG/year of CSO by 2018

150 projects implemented in only 4 years (green streets, parking lots, libraries, parks, schools, roofs, etc.) 

Created need for institutionalized approach to O & M

visit: SaveTheRain.us

Adapting an Asset Management Framework for GI Can Greatly Enhance Maintenance Effectiveness

Training Workshops

Development of Standard Maintenance Procedures (SMPs), Seasonal Considerations, Schedules

An existing Computerized Maintenance Management System (CMMS) for grey infrastructure was adapted for GI projects (MAXIMO)

Defining GI assets: type, location, quantity, etc.

Assets were linked to SMPs via CMMS and put into action by Work Orders (who/ what/when) for preventativemaintenance

Reporting & Documentation (i.e., tracking labor hours, costs, problems, etc.)

Can be tailored to specific needs of locality based on size of program, available resources and crews, and availability of a CMMS

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Partnership with Onondaga Earth Corp Entry level summer jobs for

disadvantaged youth

Public Education

4 sites maintained 2011-2012 under pilot effort

Green Streets Implementationand Green Infrastructure Maintenance

ANDREW POTTS, P.E., LEED AP, CPESC

andrew.potts@ch2m.com

MAY 1, 2014