Learn the best
resources
for managing
stormwater
in your community.
Learn the best
resources
for managing
stormwater
in your community.
Your guide to saving water and money by implementing Best Management Practices.
This Managing Rainfall: TTF Stormwater Project Tour has been funded by the League of Women Voters of Pennsylvania Citizen Education Fund through a Growing Greener grant from the Pennsylvania Department of Environmental Protection. Please visit the WREN website at www.wren.palwv.org
Table of Contents
I.
TTF Watershed and Contact Information………………………………………………...1
II.
Waterview Recreation Center (Porous Concrete, Tree Trenches)……………………….4
III.
Vernon Park (Rain Garden)………………………………………………………………….18
IV.
Womrath Park (Rain Garden)………………………………………………………………21
V.
Eadom Street Project (Depaving)…………………………………………………………26
VI.
High School Park (Rain Garden, Meadow)……………………………………………..29
VII.
Abington Junior High School (Riparian Buffer).……………………………………….33
VIII. Glenside Elementary School (Riparian Buffer)…………………….…………………..36 IX.
Arcadia University (Retention Basins)..………………………………………………….39
TTF and our Partners Contact: Tookany/Tacony-Frankford Watershed Partnership 4500 Worth Street (Globe Dye Works) Philadelphia, PA 19124 O: (215)s 744s 1853 info@ttfwatershed.org Julie Slavet, Executive Director : julie@ttfwatershed.org Brynn Monaghan, Director of Communications: brynn@ttfwatershed.org Alex Cooper, Community Engagment Coordinator:
cooper@ttfwatershed.org
This Managing Rainfall: TTF Stormwater Project Tour has been funded by the League of Women Voters of Pennsylvania Citizen Education Fund through a Growing Greener grant from the Pennsylvania Department of Education. Please visit the WREN website at wren.palwv.org
The Sustainable Lands Program is a program of the Pennsylvania Department of Conservation and Natural Resources. The program’s mission is to work with local non-profits, municipal officials, businesses and other interested parties to make sure both public and private lands are designed and maintained in an environmentally friendly and cost-effective manner. To learn more, visit www.pasustainablelands.org.
Tookany/Tacony-‐Frankford Watershed Partnership Our Watershed The Tookany/Tacony-Frankford Creek and watershed experience a host of environmental ills including impaired water quality from stormwater runoff and combined sewer overflows. Other issues are dumping and illegal uses, bank erosion, channelization, and habitat degradation in our streams and parks. The watershed includes neighborhoods in North, Northeast, and Northwest Philadelphia as well as Abington, Cheltenham, Jenkintown, Rockledge, and Springfield in Montgomery County. Home to approximately 360,000 people with a range of income levels and ethnicities in diverse communities, the creek has the potential to serve as a place for relaxation, recreation, and community connection. However, in many places the creek is compromised, attracts negative behavior, and is not recognized as a green asset.
TTF Mission and History TTF's mission is to improve the health and vitality of our watershed by engaging our communities in education, stewardship, restoration, and advocacy. TTF serves as the crucial link connecting residents, businesses and government as neighbors and watershed stewards. One of several partnerships initiated by the Philadelphia Water Department (PWD) to address water quality issues around watershed rather than municipal boundaries, TTF was created in 2000 to support existing watershed efforts. PWD, Cheltenham Township and the Pennsylvania Environmental Council joined forces to create a strong coalition of watershed stakeholders, including non-profit organizations, corporations, local governments, and residents. In 2005, TTF became the first (and only) Philadelphia-area watershed partnership to incorporate as a nonprofit organization. TTF hired its first full-time Executive Director in 2007. As a partner in the Philadelphia Water Department’s groundbreaking Green City, Clean Waters initiative, TTF initiates and supports efforts to restore the health of the watershed and mobilize its communities as watershed stewards through outreach, education, and projects. We increase public understanding, appreciation, and stewardship of our watershed and improve watershed streams, parks, and communities. Our strength is our ability to partner with public and non-profit organizations to connect environmental programs to watershed communities and residents. Through these programs, we improve our watershed while engaging watershed stewards. These hands-on activities are critical to recruiting and educating groups of concerned individuals to improve and advocate for our watershed. We have implemented a number of successful restoration projects in Philadelphia and Montgomery County watershed communities. Our commitment to these projects does not end when the project is completed. We work with local stakeholders to ensure that the project is maintained. In addition, we ensure that these projects serve as ongoing watershed classrooms by providing both signage and ongoing outreach and education. These projects include: installation of two rain gardens and facilitation of community engagement efforts at Vernon Park, a formerly underused and abused neighborhood park in Philadelphia’s Germantown and at the Olney Recreation Center Creation; and creation of three riparian buffers/outdoor classrooms at Glenside Elementary and Cedarbrook Middle Schools in Cheltenham and at Abington Junior High School. The U.S. Environmental Protection Agency recognized our efforts in 2011 by awarding us a Mid-Atlantic Region Environmental Achievement Award. Our restoration projects have been recognized with Community Greening Awards by the Pennsylvania Horticultural Society, as well as by the National Wildlife Federation as Certified Wildlife Habitat and by Audubon Pennsylvania as Bird Habitat. 1
Tookany/Tacony Frankford Watershed Partnership Stormwater Project Sites
Abington Junior HS
Glenside Elementary Arcadia University
High School Park
Waterview Recreation Center Vernon Park Rain Garden
Womrath Park Rain Garden Eadom Street Project
2
Stormwater Tour Sites and Contacts
Philadelphia:
Montgomery County:
1. Waterview Recreation Center 5826 McMahon Street Philadelphia, Pa 19144 Contact: Altje Hoekstra, Meliora Design altjeh@melioradesign.com
1. High School Park 7910 Montgomery Rd. Elkins Park, 19027 Contact: Kevin Reis, Friends of High School Park fhsprestorationmanager@gmail.com
2. Vernon Park 5800 Germantown Ave. Philadelphia, Pa 19144 Contact: Rod Ritchie, AKRF rritchie@akrf.com
2. Abington Junior High School 2056 Susquehanna Rd. Abington, PA 19001 Contact: Nancy Minich, NAM Planning and Design nancyminich6575@gmail.com
3. Womrath Park Kensington and Frankford Ave. Philadelphia, Pa 19124 Contact: Rod Ritchie, AKRF rritchie@akrf.com
3. Glenside Elementary School 400 Harrison Ave. Glenside, PA 19038 Contact: Nancy Minich nancyminich6575@gmail.com
4. Eadom Street Project Eadom and Bridge St. Philadelphia, PA 19124 Contact: Rachel Ahern, PWD Rachel.Ahern@phila.gov
4. Arcadia University 450 S Easton Road Glenside, PA 19038 Contact: Tom Macchi macchit@arcadia.edu
3
Stormwater Management Practices Downspout Planter Tree Trench Porous Concrete
Waterview Recreation Center 5826 McMahon Street Street Philadelphia, PA 19144
4
Waterview Recreation Center Project Description Waterview Recreation Center utilizes four different Green Stormwater Infrastructure Practices: Underground Infiltration, Porous Concrete, Planter Boxes and a Tree Trench System. The project was a completed by the Philadelphia Water Department, Meloria Associates and the PA Horticultural Society. The site is designed to capture, store and infiltrate the first inch of runoff from the street, sidewalk and front portion of the roof. The combination of BMP’s used serves to improve water quality, reduce stormwater runoff and act as a demonstration project for the Philadelphia Water Department. It also provides urban green space and helps reduce the urban heat island affects in the area. The project challenges include limited space, sediment laden street runoff, conflicting utilities, disturbed soils, underground structures and limited construction funds. QUICK FACTS: • • • • • • •
Cost $128,240 (according to Temple-Villanova Sustainable Stormwater Initiative) Removal of 300 linear feet of impervious sidewalk Installation of 6 foot wide porous concrete Deep (minimum 2 ft.) and shallow (6-inch) aggregate infiltration beds Four modified open-faced stormwater inlets Tree-trench system capable of capturing first Planter Boxes designed to capture first 1” of runoff 1.5” of runoff
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Waterview Recreation Center
Green infrastructure design elements: 1. Underground Infiltration Beds Stormwater inlets (similar to storm drains) are installed in the street to capture rainwater. These inlets, unlike storm
Waterview Recreation Center is located in the Tacony Creek portion of the Tookany/Tacony-
drains however, are connected to perforated pipes that distribute stormwater throughout gravel infiltration beds (layers
Frankford Watershed. It is situated at Haines Street and McMahon Street in the East Mount
of gravel designed to slow and cleanse stormwater as it passes through) and located beneath the sidewalks. Once water
Airy neighborhood of Philadelphia.
A Porous Concrete Demonstration Project The Waterview Recreation Center project is a
has been captured in the pipes, it seeps into the underground gravel beds and then into the surrounding soil. Captured water remains in the system until it has soaked completely into the Earth. In heavy rain, when the underground infiltration beds become completely filled, excess water continues to run along the curbs, bypassing the infiltration beds to enter the combined sewer system as it did before the project was implemented.
model stormwater management demonstration project, presenting the City's first porous concrete
2. Porous Concrete Sidewalks
sidewalk which also enhances the entrance of a
Porous concrete sidewalks were installed over the infiltration beds to
popular community amenity.
aid in capturing stormwater runoff from the walkways and surrounding
This green infrastructure project at Waterview
sidewalk, except for the water that flows right through it. Porous
Recreation Center demonstrates a number of
concrete allows the stormwater runoff to seep into the ground,
methods to capture stormwater runoff in an urbanized area, with the goal to filter pollutants from the stormwater runoff and to allow the stormwater to seep slowly into the ground, thereby recharging the groundwater and helping to reduce Combined Sewer Overflows (CSOs) during heavy rain events. The Waterview Recreation Center also boasts the first porous concrete sidewalk in Philadelphia!
land. The porous concrete sidewalk surface looks like a regular
recharging groundwater and reducing stormwater runoff. It shares some of the same characteristics of typical impervious concrete, but it contains tiny voids that allow stormwater and air to pass through into an underlying bed of gravel.
3. Tree Trenches A perforated pipe sends stormwater to the tree trench prior to
Porous concrete is a unique and effective means of capturing stormwater and allowing it to seep
directing the runoff to the underground infiltration beds. The trees
into the ground, recharging groundwater and reducing stormwater runoff. It has some of the same
planted in trenches (ditches) along the edge of the sidewalk help absorb
structure as typical impervious concrete, but it contains gaps that allow stormwater and air to pass
a significant amount of stormwater runoff that gets filtered by tree
through into an underlying bed of gravel.
roots, grass and soil, returning the runoff to the atmosphere through evapotranspiration.
Waterview Recreation Center was selected as a site for a stormwater retrofit demonstration project because it is in a priority sewershed (Tacony Creek Watershed) and the site allowed for the capture of off-site stormwater runoff.
Project Benefits • Reduces Combined Sewer Overflows (CSOs)
4. Flow-through Planters Connected to Downspouts Planters connected to roof downspouts allow stormwater to flow through the planters on both sides of the main entrance of the Recreation Center.. The below-grade planters fill with rainwater to a pre-determined level, and the excess overflows into pipes connected to the original storm lateral pipe. Stormwater that has been captured is absorbed by the plantings, or slowly drains through the soil into the perforated pipes lining the planter bottom that are connected back to the original storm lateral.
• Recharges groundwater • Improves water quality in creeks and rivers • Enables water and air to reach roots of street trees • Reduces stormwater runoff
Partners The design team, comprised of staff from Philadelphia Water Department (PWD), our design consultant Meliora Associates, and the Pennsylvania Horticultural Society (PHS), worked closely with the staff of Waterview Recreation Center. In addition to design funds from PWD, implementation funds were provided by the U.S. Environmental Protection Agency and the PA Department of Environmental Protection. 6
FACT SHEET: Pervious Pavement with Infiltration DESCRIPTION Pervious pavement is a Green Infrastructure (GI) technique that combines stormwater infiltration, storage, and structural pavement consisting of a permeable surface underlain by a storage/infiltration bed. Pervious pavement is well suited for parking lots, walking paths, sidewalks, playgrounds, plazas, tennis courts, and other similar uses.
Porous pavers on the right, standard asphalt on the left, in San Diego, CA
A pervious pavement system consists of a pervious surface course underlain by a storage bed placed on uncompacted subgrade to facilitate stormwater infiltration. The storage reservoir may consist of a stone bed of uniformly graded, clean and washed course aggregate with a void space of approximately 40% or other pre-manufactured structural storage units. The pervious pavement may consist of asphalt, concrete, permeable paver blocks, reinforced turf/gravel, or other emerging types of pavement.
MAINTENANCE
Porous concrete sidewalk at State College, PA
BENEFITS
Volume control & GW recharge, moderate peak rate control Versatile with broad applicability Dual use for pavement structure and stormwater management
COST
POTENTIAL APPLICATIONS Residential
Yes
Commercial
Yes
Ultra Urban
Yes
Industrial
Yes
Retrofit Highway Recreational Public
Yes Limited Yes Yes
Clean inlets Vacuum annually Maintain adjacent landscaping/planting beds Periodic replacement of paver blocks Maintenance cost: approximately $400-500 per year for vacuum sweeping of a half acre parking lot
Varies by porous pavement type Local quarry needed for stone filled infiltration bed $7-$15 per square foot, including underground infiltration bed Generally more than standard pavement, but saves on cost of other BMPs and traditional drainage infrastructure
POTENTIAL LIMITATIONS
Careful design & construction required Pervious pavement not suitable for all uses Higher maintenance needs than standard pavement Steep slopes
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KEY DESIGN FEATURES
Infiltration testing required Do not infiltrate on compacted soil Level storage bed bottoms Provide positive storm water overflow from bed Surface permeability >20”/hr Secondary inflow mechanism recommended Pretreatment for sediment-laden runoff
SITE FACTORS
Conceptual diagram showing how porous pavement functions
Porous asphalt path at Gray Towers Natl. Historic Site, PA
STORMWATER QUANTITY FUNCTIONS Volume High Groundwater High Recharge
Water Table/Bedrock Separation: 2-foot minimum Soils: HSG A&B preferred; HSG C&D may require underdrains Feasibility on steeper slopes: Low Potential Hotspots: Not without design of pretreatment system/impervious liner
Porous asphalt parking lot in Wilm., DE
STORMWATER QUALITY FUNCTIONS TSS High
ADDITIONAL CONSIDERATIONS Capital Cost
Medium
TP
Medium
Maintenance
Medium
Peak Rate
Medium/High
TN
High
Winter Performance
Medium/High
Erosion Reduction
Medium/High
Temperature
High
Fast Track Potential
Low/Medium
Flood Protection
Medium/High
Aesthetics
Low/Medium
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FACT SHEET: Infiltration Practices DESCRIPTION Infiltration practices are natural or constructed areas located in permeable soils that capture, store, and infiltrate the volume of stormwater runoff through a stone-filled bed (typically) and then into surrounding soil. Dry wells, also referred to as seepage pits, French drains or Dutch drains, are a subsurface storage facility (structural chambers or excavated pits, backfilled with a coarse stone aggregate or alternative storage media) that temporarily store and infiltrate stormwater runoff from rooftop structures. Due to their size, dry wells are typically designed to handle stormwater runoff from smaller drainage areas, less than one acre in size.
BENEFITS
Reduces volume of stormwater runoff Reduces peak rate runoff Increases groundwater recharge Provides thermal benefits Increased aesthetics Multiple use/Dual use
MAINTENANCE There are a few general maintenance practices that should be followed for infiltration BMPs. These include:
All catch basins and inlets should be inspected and cleaned at least twice per year The overlying vegetation of subsurface infiltration feature should be maintained in good condition and any bare spots revegetated as soon as possible. Vehicular access on subsurface infiltration areas should be prohibited (unless designed to allow vehicles) and care should be taken to avoid excessive compaction by mowers.
POTENTIAL LIMITATIONS
Pretreatment requirement to prevent clogging Not recommended for areas with steep slopes
Infiltration basins are shallow surface impoundments that temporarily store, capture, and infiltrate runoff over a period of several days on a level and uncompacted surface. Infiltration basins are typically used for drainage areas of 5 to 50 acres with land slopes that are less than 20 percent. Infiltration berms use a site’s topography to manage stormwater and prevent erosion. Berms may function independently in grassy areas or may be incorporated into the design of other stormwater control facilities such as Bioretention and Constructed Wetlands. Berms may also serve various stormwater drainage functions including: creating a barrier to flow, retaining flow for volume control, and directing flows. Infiltration trenches are linear subsurface infiltration structures typically composed of a stone trench wrapped with geotextile which is designed for both stormwater infiltration and conveyance in drainage areas less than five acres in size. Subsurface infiltration beds generally consist of a rock storage (or alternative) bed below surfaces such as parking lots, lawns, and playfields for temporary storage and infiltration of stormwater runoff with a maximum drainage area of 10 acres. Bioretention can be an infiltration practice and is discussed in the Bioretention fact sheet.
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COST Dry Well: Construction costs – $4-9/ft3, Maintenance Costs – 5-10% of capital costs Infiltration basin: Construction costs – varies depending on excavation, plantings, and pipe configuration Infiltration Trench: Construction costs – $20-30/ft3, Maintenance Costs – 510% of capital costs Subsurface Infiltration Bed: Construction costs – 13/ft3
VARIATIONS Rain barrels Cistems, both underground and above ground Tanks Storage beneath a surface using manufactured products Various sizes, materials, shapes, etc. KEY DESIGN FEATURES Depth to water table or bedrock Pretreatment is often needed to prevent clogging Often required level infiltration surface Proximity to buildings, drinking water supplies, karst features, and other sensitive areas Soil types (permeability, limiting layer, etc.) Provide positive overflow in most uses
Subsurface Infiltration Bed using Rainstore ™ blocks for storage media, Washington National Cathedral, DC
SITE FACTORS Maximum Site Slope: 20 percent Minimum depth to bedrock: 2 feet Minimum depth to seasonally high water table: 2 feet Potential Hotspots: yes with pretreatment and/or impervious liner HSG Soil type: A and B preferred, C & D may require an underdrain Maximum drainage area – N/A
Potential Applications
Dry Well Infiltration Basin Infiltration Berm Infiltration Trench Subsurface Infiltration Bed
Residential
Commercial
Ultra Urban
Industrial
Retrofit
Highway/ Road
Recreational
Private
Yes
Yes
Yes
Limited
Yes
No
Yes
Yes
Yes
Yes
Limited
Yes
Yes
Limited
Yes
Yes
Yes
Yes
Limited
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Limited
Yes
Yes
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Stormwater Quantity Functions
Dry Well Infiltration Basin Infiltration Berm Infiltration Trench Subsurface Infiltration Bed
Volume
Groundwater Recharge
Peak Rate
Erosion Reduction
Flood Protection
Medium High Low/Medium Medium
High High Low/Medium High
Medium High Medium Low/Medium
Medium Medium Medium/High Medium/High
Low High Medium Low/Medium
High
High
High
Medium/High
Medium/High
Stormwater Quality Functions Dry Well Infiltration Basin Infiltration Berm Infiltration Trench Subsurface Infiltration Bed
TSS
TP
TN
Temperature
Medium (85%) High (85%) Medium/High (60%) Medium (85%) High (85%)
High/Medium (85%) Medium/High (85%) Medium (50%) High/Medium (85%) Medium/High (85%)
Medium/Low (30%) Medium (30%) Medium (40%) Medium/Low (30%) Low (30%)
High High Medium High High
The Vegetated Infiltration Basin beneath this playfield manages rooftop runoff from the adjacent school building, Philadelphia, PA
Infiltration trench Chester County, PA
Level Spreader for Even Distribution Gently Sloping Sides
Additional Considerations Capital Cost
Medium
Life Cycle Costs
Medium
Maintenance
Medium
Winter Performance
High
Resistance to Heat
High
Fast Track Potential
Medium
Aesthetics
Medium
Vegetated Infiltration Basin outside of Allentown, PA
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FACT SHEET: Stormwater Planter Box DESCRIPTION A Planter Box is a container or enclosed feature located either above ground or below ground, planted with vegetation that captures stormwater within the structure itself. Planter Boxes can play an important role in urban areas by minimizing stormwater runoff, reducing water pollution, and creating a greener and healthier appearance by retaining stormwater rather than allowing it to directly drain into nearby sewers. Planter Boxes receive runoff usually from rooftop areas and must be located reasonably close to downspouts or structures generating runoff. Stormwater runoff is used to irrigate the plants, and the vegetation in the planter box reduces stormwater through evapotranspiration.
Planter box in Lansing, Michigan
BENEFITS Enhance site aesthetics and habitat Potential air quality and climate benefits Potential runoff and combined sewer overflow reductions Wide applicability including ultra-urban areas POTENTIAL APPLICATIONS Residential
Yes
Commercial
Yes
Ultra Urban
Yes
Industrial
Limited
Retrofit
Yes
Highway/Road
Limited
Recreational
Limited
Private
Yes
Boxes can take any number of different configurations and be made out of a variety of different materials, although many are constructed from wood or concrete. Underground Planter Boxes designed to infiltrate can be constructed alongside buildings provided that proper waterproofing measures are used to protect foundations. MAINTENANCE See Rain Garden maintenance Bypass valve during winter Maintenance cost: $400-$500 per year for a 500 square foot planter; varies based on type, size, plant selection, etc. COST Varies based on type, size, plant selection, etc., but is approx. $8-15 per square foot POTENTIAL LIMITATIONS Limited stormwater quantity/quality benefits Relatively high cost due to structural components for some variations
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VARIATIONS Contained (above ground) Infiltration (below ground) Flow-through KEY DESIGN FEATURES Native vegetation May be designed as pretreatment May be designed to infiltrate Captured runoff to drain out in 3 to 4 hours after storm even unless used for irrigation Receive less than 15, 000 square feet of impervious area runoff (typ.) The structural elements of the planters should be stone, concrete, brick, or pressure-treated wood Flow bypass during winter
Conceptual diagram showing infiltration
Infiltration planter box at Woodlawn Library, Wilmington, DE
STORMWATER QUANTITY FUNCTIONS
SITE FACTORS Water Table and Bedrock Depth – N/A for contained and flow-through, 2 feet minimum for Infiltration Planter Box Soils – N/A for contained and flowthrough, HSG A&B preferred for Infiltration Potential Hotspots – yes for contained and flow-through; no for infiltration
STORMWATER QUALITY FUNCTIONS
ADDITIONAL CONSIDERATIONS
Volume Groundwater Recharge
Low/Medium
TSS
Medium
Capital Cost
Low/Medium
Low
TP
Medium
Maintenance
Medium
Peak Rate
Low
TN
Medium
Erosion Reduction
Low
Temperature
Medium
Flood Protection
Low
Winter Performance Fast Track Potential Aesthetics
Medium Low High
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FACT SHEET: Tree Trench DESCRIPTION Tree trenches perform the same functions that other infiltration practices perform (infiltration, storage, evapotranspiration etc.) but in addition provide an increased tree canopy. MAINTENANCE Tree trench in urban setting (Viridian Landscape Studio)
Water, mulch, treat diseased trees, and remove litter as needed Annual inspection for erosion, sediment buildup, vegetative conditions Biannual inspection of cleanouts, inlets, outlets, etc. Maintenance cost for prefabricated tree pit: $100-$500 per year
BENEFITS
COST
Increased canopy cover Enhanced site aesthetics Air quality and climate benefits Runoff reductions Water quality benefits High fast track potential Enhanced tree health/longevity
POTENTIAL APPLICATIONS Residential
Yes
Commercial
Yes
Ultra Urban
Limited
Industrial
Yes
Retrofit
Yes
Highway/Road
Yes
Recreational
Yes
Public/Private
Yes
$850 per tree $ 10-$15 per square foot $8000-$10,000 to purchase one prefabricated tree pit system including filter material, plants, and some maintenance; $1500-$6000 for installation
POTENTIAL LIMITATIONS
Required careful selection of tree species Required appropriate root zone area Utility conflicts, including overhead electric wires, posts, signs, etc. Conflicts with other structures (basements, foundations, etc.)
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VARIATIONS
Structural soil or alternative (eg. Silva Cell) Porous pavers Open vegetated tree trench strip (planted with ground cover or grass) Tree grates Alternate storage media (modular storage units) Prefabricated tree pit
KEY DESIGN FEATURES
Flexible in size and infiltration Native Plants Quick drawdown Linear infiltration/storage trench Adequate tree species selection and spacing New inlets, curb cuts, or other means to introduce runoff into the trench
SITE FACTORS
Overhead clearance; minimize utility conflict Root zone Water table Soil permeability/Limiting zones
TOP LEFT: Tree trench with porous pavers and subsurface infiltration bed, located in City Lot No. 21, Syracuse, NY LEFT: Tree trench located at Upper Darby Park outside of Philadelphia, PA
STORMWATER QUANTITY FUNCTIONS
STORMWATER QUALITY FUNCTIONS
ADDITIONAL CONSIDERATIONS
Volume Groundwater Recharge
Medium
TSS
High (70-90%)
Capital Cost
Medium
Medium
TP
Medium (60%)
Maintenance
Medium
Peak Rate
Medium
TN
Erosion Reduction
Medium
Temperature
Medium (4050%) High
Winter Performance Fast Track Potential
Flood Protection
Low/Medium
Aesthetics
High High High
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Example of Tree Trench adjacent to a Subsurface Infiltration Bed
Example of Street Tree Trench with Structural Soil and Adjacent Infiltration Trench – Cross-Section A
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Example of Street Tree Trench with Structural Soil and Adjacent Infiltration Trench – Cross-Section B
Example of Street Tree Trench with Structural Soil and Adjacent Infiltration Trench – Cross-Section C
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Stormwater Management Practice Rain Garden
Vernon Park 5818 Germantown Avenue Philadelphia, PA 19144
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Vernon Park Rain Garden At intersection of Germantown Ave. and Greene St. Philadelphia, PA 19144
Project Description The rain garden project at Vernon Park was led by TTF and funded by the Philadelphia Water Department in partnership with many key stakeholders including Philadelphia Parks & Recreation, the Pennsylvania Horticultural Society, the Fairmount Park Conservancy, and the Friends of Vernon Park. An area that was previously covered with turf was re-graded and used for the construction of an approximately 757 squarem foot rain garden. This stormwater infrastructure was designed to manage the first inch of stormwater runoff generated from approximately 4,361 square feet of a portion of the building’s roof and adjacent sidewalk area. The first inch of rain is captured and diverted from the City’s stormwater sewer by six (6) downspout diversion pipes, which convey the runoff to the rain garden through a series of swales and PVC pipes under the sidewalk. Some of the sidewalk areas sheet-‐flow into the rain garden. The rain garden is designed to capture and infiltrate a volume of approximately 395 cubic feet of stormwater and divert any overflow, produced by larger rain events, through a spillway into an existing inlet structure immediately adjacent to the facility. • • • •
QUICKFACTS 757 Square-‐foot Garden Six downspout diversion pipes 4,361 square feet of impervious cover captured 395 cubic feet of stormwater capture (nearly 3,000 gallons)
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Stormwater Management Practice Rain Garden
Womrath Park Intersection of Frankford Ave. & Kensington Ave. Philadelphia, PA 19124 Â
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FACT SHEET: Bioretention (Rain Gardens) DESCRIPTION
Residential rain garden at the Village at Springbrook Farm in Lebanon, PA
Bioretention Areas (often called Rain Gardens) are shallow surface depressions planted with specially selected native vegetation to treat and capture runoff and are sometimes underlain by sand or gravel storage/infiltration bed. Bioretention is a method of managing stormwater by pooling water within a planting area and then allowing the water to infiltrate the garden. In addition to managing runoff volume and mitigating peak discharge rates, this process filters suspended solids and related pollutants from stormwater runoff. Bioretention can be designed into a landscape as a garden feature that helps to improve water quality while reducing runoff quantity. Rain Gardens can be integrated into a site with a high degree of flexibility and can balance nicely with other structural management systems including porous pavement parking lots, infiltration trenches, and other non-structural stormwater BMPs. Bioretention areas typically require little maintenance once established and often replace areas that were intensively landscaped and require high maintenance.
MAINTENANCE Rain garden at Woodlawn Library in Wilmington, DE
BENEFITS
Volume control & GW recharge, moderate peak rate control Versatile w/ broad applicability Enhance site aesthetics and habitat Potential air quality & climate benefits
POTENTIAL APPLICATIONS Residential
Yes
Commercial
Yes
Ultra Urban
Limited Yes Yes Yes Yes Yes
Industrial Retrofit Recreational Public/Private Residential
Watering: 1 time / 2-3 days for first 1-2 months, then as needed Spot weeding, pruning, erosion repair, trash removal, and mulch raking: twice during growing season As needed, add reinforcement planting to maintain desired density (remove dead plants), remove invasive plants, and stabilize contributing drainage area Annual: spring inspection and cleanup, supplement mulch to maintain a 3 inch layer, and prune trees and shrubs At least once every 3 years: remove sediment in pretreatment cells/inflow points and replace the mulch layer Maintenance cost is similar to traditional landscaping
COST
Cost will vary depending on the garden size and the types of vegetation used; typical costs are $10-17 per sq. foot
POTENTIAL LIMITATIONS
Higher maintenance until vegetation is established Limited impervious drainage area to each BMP Requires careful selection & establishment of plants
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VARIATIONS
Subsurface storage/infiltration bed Use of underdrain Use of impervious liner
KEY DESIGN FEATURES
Conceptual diagram showing process of bioretention
Flexible in size and configuration Ponding depths 6 to 18 inches for drawdown within 48 hours Plant selection (native vegetation that is tolerant of hydrologic variability, salts, and environmental stress) Amend soil as needed Provide positive overflow for extreme storm events Stable inflow/outflow conditions
SITE FACTORS
Water Table/ Bedrock Separation: 2-foot minimum, 4-foot recommended Soils: HSG A and B preferred; C & D may require an underdrain Feasibility on steeper slopes: medium Potential Hotspots: yes with pretreatment and/or impervious liner Maximum drainage area: 5:1; not more than 1 acre to one rain garden
Linear bioretention area along roadway Source: Low Impact Development Center, Inc. Sou
STORMWATER QUANTITY FUNCTIONS
STORMWATER QUALITY FUNCTIONS
ADDITIONAL CONSIDERATIONS
Volume
Medium/High
TSS
High (70-90%)
Capital Cost
Medium
Groundwater Recharge
Medium/High
TP
Medium (60%)
Maintenance
Medium
Peak Rate
Medium
TN
Medium (40-50%)
Winter Performance
Medium
Erosion Reduction
Medium
Temperature
High
Fast Track Potential
Medium
Flood Protection
Low/Medium
Aesthetics
High
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Stormwater Management Practice Depaving
Eadom Street Project Intersection of Frankford Ave. & Kensington Ave. Philadelphia, PA 19124 Â
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Eadom Street Depaving Project
Project Description Depaving clears space for lush and attractive yard spaces that filter pollutants from our water and air and provide numerous ecological benefits. By removing an impervious surface such as concrete or asphalt, water can be absorbed into the ground, recharging groundwater aquifers. The Philadelphia Water Department’s Waterways Restoration Team undertook the Eadom Street Depaving Project. The project was initiated in the Winter of 2011 and final planting was completed on April 30th, 2013. The parking lot was surveyed for placement of a depaved area that could capture the first 1” of runoff. The Office of Watersheds came up with several concept designs before deciding on a bioretention feature in the place of the asphalt. The Water Department Waterways Restoration team were responsible for the coordination of construction, installation or stone, topsoil and plants. The planting utilized volunteers and outreach to the community.
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Eadom Street Green Lot Celebration June 29, 2012 12PM 5312-50 Eadom Street, Frankford
Join us for: a tour of the site environmental activites a ribbon cutting refreshments a ceremony for the NET volunteers
Please join us as we celebrate the completion of the Eadom Street green parking lot and the NorthEast Treatment patients who have adopted the model site! Thanks to community volunteers, NorthEast Treatment Center (NET) patients and the Philadelphia Water Department, Philadelphia can boast its first green parking lot! Ten thousand square feet of pavement has been replaced with rain gardens that will manage stormwater runoff on-site, protecting Philadelphia’s waterways. The rain gardens will also add much needed greenery to the landscape while also serving as a model for green parking lots across the City. Come celebrate the success of the project and the new Eadom Street Rain Garden Adoptees! The NET Center patients have pledged to help keep the rain gardens clean and beautiful for the enjoyment of the whole community.
Completed rain gardens, Eadom Street, Frankford, Philadelphia
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Stormwater Management Practices Rain Garden Meadow Restoration
Friends of High School Park 7910 Montgomery Ave. Elkins Park 19027
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High School Park Meadow and Edge Restoration Project Elkins Park, PA A partnership project between: DCNR, Cheltenham Township, Friends of High School Park, and Sikora-Wells Appel
As part of the first phase of a grant from DCNR, the meadow restoration project tries to reclaim a former property where the Cheltenham High School used to be. In Phase I, the meadow was designed to provide an aesthetic quality to the park and surrounding community while providing suitable habitat to birds and insects. The meadow also helps control storm water which, in the past, would erode away the hillside on its way to the creek. In Phase II, a rain garden will be constructed at the top of the grand staircase between the meadow and the woodland. The rain garden will be designed to accept approximately 10% of a typical rain event. Additional hardscaping and park entranceway improvements will also be done as a part of the grant. The Friends of High School Park will be performing in-kind service hours which will focus on invasive plant removal along the woodland edge. These areas will then be planted with native shrubs and grasses.
Figure 1. A drawing, by Sikora-Wells Appel, of High School Park showing invasive plants along the meadow edge.
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Figure 2. A cross section, by Sikora-Wels Appel, of the proposed rain garden.
Figure 3. A grading plan, by Sikora-Wells Appel, of the proposed rain garden
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What is a Rain Garden? • A rain garden is a shallow, planted depression that is designed to collect runoff from impervious surfaces such as rooftops, sidewalks and parking lots • By collecting runoff water from rain and snowstorms, rain gardens can filter out pollution and prevent it from contaminating our local rivers and streams • The collected runoff waters on-site plants, creating much needed urban green space
Rain garden site before construction, Eadom Street, Philadelphia
Rain garden construction in progress, Eadom Street, Philadelphia
Rain Garden To learn more about rain gardens and other types of green infrastructure, please visit www.phillywatersheds.org
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Stormwater Management Practice Riparian Buffer
Abington Junior High School 2056 Susquehanna Rd. Abington, PA 19001
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Abington Junior High School Riparian Buffer This riparian buffer project was led by TTF and funded by a TreeVitalize Watershed grant from the Pennsylvania Department of Environmental Protection & Aqua Pennsylvania, as well as a grant from an anonymous source, in partnership with the Abington School District, Abington Environmental Advisory Council, and Briar Bush Nature Center. The Abington Junior High School has become a model for using Best Management Practices to limit water pollution from non-point sources. The School District campus forms the headwaters of East Baeder Creek, a firstu order stream that contributes to the Tookany Creek. The vast Abington School District Campus has numerous opportunities to improve the health of the Tookany Creek. The school was so pleased with their first buffer planting in 2012 that they planted a second phase in 2013. The school is currently working on a Phase III to capture stormwater runoff from their parking lot and treat it with bioswales. Abington Junior High School Facts: • Phase I Buffer was 8,000 square feet (200 ft. X 40 ft.) • Phase II Buffer an additional 8,000 square feet (200 ft. X 40 ft.) • Before restoration, the vegetation cover was 60% invasive • 25 different types of native plants were re-‐introduced • Once established, the successional forest buffer will provide shade for aquatic life • Plantings were done with all volunteer labor
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Stormwater Management Practice Riparian Buffer
Glenside Elementary School 400 Harrison Ave. Glenside, PA 19038
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In 2008, Glenside Elementary School students and community partners created a riparian buffer along Tookany Creek, replacing invasive plants with native trees, shrubs, wildflowers and grasses. These plants provide a much-needed buffer between the school's lawn and the creek.
Glenside Elementary
e Limekiln Pik
Glenside Elementary School
Riparian Buffer Planting
About the TTF Watershed Partnership
Harrison Avenue
Initiated by a Glenside Elementary School teacher and implemented by the Tookany/Tacony-Frankford Watershed Partnership, Glenside Elementary School, Glenside Elementary Parent Teacher Organization, Cheltenham Township Environmental Advisory Council and NAM Planning & Design, LLC, the project was made possible by a TreeVitalize grant.
Riparian Buffer (250í x 25í)
Tookany Creek
The mission of the Tookany/Tacony-Frankford Watershed Partnership (TTF) is to enhance the health and vitality of the Tookany/Tacony-Frankord Creek and its watershed, serving as the crucial link connecting residents, businesses and government as neighbors and stewards of this impaired, but critically important 29 square mile watershed in the Philadelphia region. TTF initiates and supports efforts to restore the health of the watershed and mobilize its communities as watershed stewards through community outreach, networking, educational programs, and project coordination. We increase public understanding, appreciation, and stewardship of our watershed and improve watershed streams, parks, and communities.
What You Can Do To Protect The Tookany Creek Plant a vegetable, rain or rooftop garden. Grow potted plants on paved areas. Let lawns grow taller and minimize use of fertilizer and chemicals. Install a rain barrel at your home to catch rainwater for your use. Learn about invasive plants and remove them from your property. Replace lawn grass with a native wildflower meadow. Convert your roof into a green roof. Avoid high water-usage activities like washing dishes, showering and laundry when it’s raining. Put trash in trash receptacles, not in storm drains or on the ground. Dispose of dog waste in the trash or toilet so it does not carry bacteria into the creek Fix cars that leak oil or antifreeze onto the pavement. Use less salt on driveways and sidewalks in winter. Mix it with sand to help with traction. Recycle your electronics ethically— don’t send them to a landfill where they leak toxic chemicals into our land and waterways. Volunteer with a local environmental or park group.
Riparian Buffer Benefits The benefits of this riparian buffer include: improved stormwater infiltration, enhanced wildlife habitat, decreased non-point source pollution, and increased opportunity for watershed education and stewardship. Native plants do most of the work to protect Tookany Creek by preventing erosion of the stream banks, helping to absorb and filter stormwater, and keeping fertilizers, salt and other pollutants out of the creek. Glenside Elementary School
This buffer also provides students with hands-on learning about watershed ecology while protecting the health of the creek. In this natural outdoor classroom, students will study soil, insects and plants as an integral part of the science curriculum for years to come.
Location in Cheltenham Township and along the Tookany Creek Location in the Tookany/Tacony-Frankford Watershed
August 2008 Lawn before riparian buffer was planted
April 2009 Holes dug and plants ready for installation
April 2009 Students learn to plant native trees, shrubs, wildflowers and grasses
April 2009 Students take the lead in planting the buffer
April 2009 Students have fun planting
April 2009 Students, teachers and volunteers work together
August 2009 Flourishing riparian buffer complete with wildflowers and healthy dense plants
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N a t i v e P l a n t s i n t h i s R i p a r i a n B u ff e r Black Oak
Willow O a k
I r o n wo o d
S we e t b ay Mag n o l i a
R e d Map l e
Sweet Birch
S w a m p Wh ite Oak
Elde rbe rry
Redbud
S y c amo r e
Silver Maple
Ye l l o w B i r c h
S c a rl e t O ak
Flowe ring D ogwood
S h ad b l o w
Wi t c h H az e l
S u g ar M a p l e
Grey Birch
B u t t o n b u sh
Silky D ogwood
Gr e y D o g wo o d
R e d - t wi g g e d D o g wo o d
Bay b e r r y
B l a c k - e y e d S u san
N e w York A st e r
N e w En g l an d A s t e r
Mo n k e y F l o we r
Sedges
Rushe s
R i v e r b an k R y e
{ Q u e r c u s v e l u t in a}
{ Q u e r c u s b i c o l o r}
{ Q u e r c u s c o c c i nea}
{ C e p h a l e n t h i s occi d en tal i s}
{ R u d b e c k i a h i r ta}
{Carex species}
NAM Planning & Design, LLC L ands cape-Archi t ect ure | P l anni ng | R est o r a t io n | Ma n a g e me n t | Ho r t ic u lt u r e - Th e r a p y
{Quercus phellos}
{Sambucus canadensis}
{Cornus florida}
{Cornus amomium}
{Aster novi-belgi}
{Juncus species}
{ C a r pi nus c a r o l i a na }
{ C e r c i s c a na de ns i s }
{ A me l a nc hi e r c a na de ns i s }
{ C o r nus r a c e mo s a }
{ A s te r no v a e -a ng l i a e }
{ E l y mus r i pa r i c us }
{ M a g no l i a v i r g i ni a na }
{ P l a ta no us o c c i de nta l i s }
{ Ha ma me l i s v i r g i ni a na }
{ C o r nus s e r i c e a }
{ M i mul us r i ng e ns }
{ A c e r r ubr um}
{ A c e r s a c c ha r i n u m }
{ A c e r s a c c ha r u m }
{ M y r i c a pe nns y lv a n ic u m }
{ Be t u la le n t a }
Trees
{ Be t u la a lle g h a n e n s is }
{ Be t u la p o p u lif o lia }
Shrubs
Wildflowers
Grasses
Funded in part through a grant from: TreeVitalize, Royal Bank of Canada, Tookany Tacony / Frankford Watershed Partnership Project Partners: Students, Teachers and Parents of Glenside Elementary School; Glenside Elementary School PTO; Cheltenham Township School Board; Cheltenham Township Environmental Advisory Commission; Tookany Tacony / Frankford Watershed Partnership; Arcadia University Environmental Network; and many more dedicated community volunteers
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Stormwater Management Practices Retention Basins Porous Pavement Bio-swales Stream Restoration
Arcadia University 450 S. Easton Road Glenside, PA 19038
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Campus Building Key 1. 2. 3. 4. 5. 6. 7. 8. 9.
Grey Towers Castle Health Science Center Easton Hall Brubaker Hall Murphy Hall Spruance Fine Arts Center Commons Kuch Athletic & Recreation Center Boyer Hall of Science
10. 11. 12. 13. 14. 15. 16. 17. 18.
Landman Library Taylor Hall Knight Hall Heinz Hall Blankley Alumni House Dining Complex Dilworth Hall Thomas Hall Kistler Hall
4500 Worth Street, Philadelphia, PA 19124 215t 744t 1853 www.ttfwatershed.org
Green Campus, Clean Waters Clean Water Projects at Arcadia University
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Swale and Historic Stream
Rain water that cannot be contained in the underground parking lot retention basins is diverted into this green space. The historic stream that was cut off by Route 309 sometimes makes an appearance running through this site.
Easton Field Retention Basin
Underneath this new athletic field is a basin that collects the rainwater that falls on the field. Covers are installed on the underground discharge pipes to prevent floatable litter from draining into the creek.
Ro ute
30 9
on Ro ad
Easton Field Rain Garden
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1 18
Ea st
This water management tool is designed to hold on to rain water and encourage it to soak into the ground. This design contains rainwater close to where it falls, keeping it from rushing down the road and picking up pollutants.
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5
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Porous Pavers
Limekiln Pike
This fire lane was revamped with pavers that allow water to soak into the ground. The fire lane design also includes grated sections where you can see the historic stream, which was cut off by Route 309, traveling underground.
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14 13 12
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Weiss Tennis Courts/The Dome
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Chu rch Roa d
Blankley Field
Campus Commons Retention Basin
Creek-‐side Invasive Removal
Natural means were used to remove invasive species of plants from this creek restoration site. This process involved returning year after year to cut down and remove all the plants. By using this method herbicides were avoided, which takes away the danger of chemicals getting in the creek and doing harm downstream.
Underneath this green space, which appears like any other campus commons, is a basin. This basin holds the rainwater that flows off of nearby buildings and traps floatable litter to keep it from traveling down to the creek.
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Managing Rainfall: Stormwater Tour is a Splash! Posted on October 21, 2013 There’s a lot of curiosity about the Green City, Clean Waters plan and the use of Green Stormwater Infrastructure in Philadelphia — how the city is using gardens, planters, and innovative technology to manage stormwater, rather than relying exclusively on traditional grey infrastructure and pipes to solve our stormwater runoff challenge. Green Stormwater Infrastructure (GSI) systems improve the health of our streams, as well as providing numerous benefits to the community, such as jobs, cleaner air, and improved quality of life. In response to requests from stakeholders across our watershed, TTF recently launched Managing Rainfall: TTF Stormwater Tours with funding from the Water Resource Education Network (WREN) of the Pennsylvania League of Women Voters Citizen Education Fund through a Growing Greener grant from the Pennsylvania Department of Environmental Protection. Targeted at municipal officials, staff, and volunteers, these tours provide an opportunity to showcase innovative projects, including one that TTF led! We kicked off the two part tour series on Thursday, October 10. The first tour drew fifteen participants including Environmental Advisory Committee members, local public works employees, staff from Pennsylvania Representative Steve McCarter, TTF and Friends of High School Park Board members, employees of the US Environmental Protection Agency, Philadelphia Water Department (PWD) staff, and interested citizens. For those of you who may not remember last Thursday, it was wet! It was perfect weather to showcase how stormwater management features work. We watched the GSI “soak up” the rain while project specialists from the Philadelphia Water Department, and the firms AKRF, Inc. and Meliora Design described how these stormwater management practices operate.
At Germantown’s Waterview Recreation Center, Meliora Design’s Altje Hoekstra described Philadelphia’s first porous concrete sidewalk, as well as a stormwater planter and tree trenches. The tour then visited the rain garden in Vernon Park, the Emerald of Germantown. This garden was planned and constructed by TTF in collaboration with AKRF, Inc. along with many community organizations and residents. We then crossed the city to Frankford’s Womrath Park rain garden. AKRF engineer Rod Ritchie presented information about both the Vernon and Womrath Park rain gardens. Participants had the chance to see the technical work that goes into these types of installations and the smaller engineered components — the diversion downspouts, overflow pipes, stormwater inlets, and drains – that often go unnoticed amid the colorful plants and flowers. Eadom Street was the last stop on the tour. PWD’s Office of Watersheds designed and carried out this depaving project, which converted sections of underused parking lot into a pervious, attractive and ecologically beneficial space. PWD landscape architect Rachel Ahren gave the group an overview of the project’s conceptual stage and installation. Following the tour, a soggy-yet-enthusiastic bunch of participants gathered at the TTF office for further discussion over hot tea and snacks. Participants expressed their varying levels of familiarity with managing stormwater. For many, this was the first time that they had seen porous concrete or a rain garden. Others shared that the tour provided them with specific practices to apply to existing sites. Interested in touring these sites? In response to all the interested folks we’ve heard from who could not join us on this first tour, we will provide the same tour again on Friday, November 8th. To register and for more information, contact Alex Cooper at cooper@ttfwatershed.org. In the spring, TTF will showcase projects in Montgomery County.
Glenside News Globe Times Chronicle > Opinion LETTER: Take a stormwater project tour with Tookany/Tacony-Frankford Watershed Partnership Published: Thursday, March 27, 2014 To the Editor: While we all know that flooding is a problem in our communities, many of us are also concerned about the related stormwater runoff problem that is the major source of pollution of our waterways. Here in Eastern Montgomery County, we are lucky to count as assets the creeks and tributaries that run through our backyards, under our streets, through our parks and school campuses. The Tookany/Tacony-Frankford Watershed Partnership has been working hard to improve the health of our 30-square mile TTF watershed and creeks by actively engaging our communities in education, stewardship, restoration and advocacy. We are proud to be supported by and work closely with our upstream communities of Abington, Cheltenham and Springfield townships and the boroughs of Jenkintown and Rockledge, as well as our downstream partner, the City of Philadelphia. Join us to learn the best resources for managing stormwater in your community with green infrastructure, an approach that works with nature, capturing, storing and infiltrating polluted stormwater before it reaches a drain that carries it to our streams. We invite our elected officials plus members of municipal and civic committees and organizations to our Managing Rainfall: TTF Stormwater Project Tour April 2 from 1 to 3:30 p.m. This tour will visit green infrastructure and restoration projects here in our upstream communities! Our first tour last October was productive and well attended; the tour featured rain gardens, porous concrete, depaving and tree trenches, all located within our watershed in Philadelphia. In fact, Cheltenham Commissioner Ann Rappoport’s letter about the tour (“Stronger than floods”) was printed in the Philadelphia Inquirer stating, “These stormwater projects showed us how effective such practices can be.” Jenkintown Borough board member Christian Soltysiak remarked, “Our community is so built-out, you wouldn’t think you could build these gardens, but some of these tools could work in tight areas.” Be a watershed leader and join us on this free tour! Here is a link to the tour flyer:http://archive.constantcontact.com/fs132/1102671118014/archive/1116745493299.html. To RSVP or ask a question, email cooper@ttfwatershed.org or call 215-744-1853. You can learn more about the October tour here: http://ttfwatershed.org/2013/10/21/managing-rainfall-stormwater-tour-isa-splash/. These tours are funded by the League of Women Voters Citizen Education Fund through a Growing Greener grant from the Pennsylvania Department of Environmental Protection. Visit the WREN website at www.wren/palwv.org. Julie Slavet Executive Director
The Inquirer: Letters to the Editor Published Tuesday, October 22, 2013, 2:01 AM Stronger than floods A recent field trip run by the Tookany/Tacony-Frankford Watershed Partnership, city and state agencies, and civic groups surveyed various green storm-water infrastructure practices designed to help curtail flooding, water contamination, sewer overflows, blight, and groundwater depletion. We saw depaving projects, sizable planters, tree trenches, porous concrete, and extensive garden rainfiltration efforts, in addition to underground holding tanks among other best practices. Engineers translated technicalities; designers described other features. Costs, funding sources, challenges, and benefits were part of the discussions. Heavy downpours drenched us on the field trip, but these storm-water projects showed us how effective such practices can be. So, the next time you curse having to mow the grass, or watch rivers of wasted water flowing down your street, stop to consider that brilliant alternatives exist. We need to start implementing them. Ann L. Rappoport, Wyncote