The Pennsylvania Department of Conservation and Natural Resources has recently asked us, along with some other LA’s in the State, to review and comment on their new Stormwater BMP Guide for Parks. The guide is for grantees to use and apply to their sites. Below is the final version:
Rain Garden- an excavated shallow surface depression planted with specially selected native vegetation to treat and capture runoff. Rain gardens should be located in well-drained soils. They allow stormwater to be absorbed by plants and infiltrated into the groundwater.
How can you apply this in your park? A simple rain garden can be located near a walkway, parking lot, court area, or other paved surface to absorb stormwater runoff. Native vegetation that thrives in wet conditions should be planted to enhance the water absorption capabilities of the rain garden. Additional benefits of native vegetation may include creating habitat areas for wildlife and birds and aesthetic enhancement of the site. This type of design is inviting to park visitors and educational signage can illustrate how a simple rain garden design can be created at home to reduce stormwater runoff.
Pervious Pavement- consists of a permeable pavement (surface course) underlain by a uniformly-graded stone bed which provides temporary storage for stormwater runoff and promotes infiltration. The surface course may consist of porous asphalt, porous concrete, or various porous structural pavers laid on uncompacted soil.
How can you apply this in your park? Pervious pavement can be used in parking areas, on basketball and tennis courts, for trails and walkways, etc. Use of pervious pavement is not practical for wooded or flood prone areas due to sediment and leaf-litter filling the porous voids of the pavement. In open areas, use of pervious pavement provides the added benefit of managing stormwater beneath the surface, minimizing disruption of additional areas for the management of stormwater and the costs associated with construction of a stand-alone stormwater management facility. For large parking lots consider a mix of surface types that include turf parking with a gravel base, aggregate paving for traffic aisles, and pervious paving for parking stalls.
Riparian Areas- a permanent area of trees and shrubs located adjacent to streams, lakes, ponds, and wetlands. Riparian forests are the most beneficial type of buffer for they provide ecological and water quality benefits.
How can you apply this in your park? Enhance the areas adjacent to rivers, streams, wetlands and ponds with native vegetation or create a “no mow zone” with meadow grasses that is at least 35’ wide on all sides. Be sure to include public access points where appropriate so park visitors can enjoy these water resources. Interpretative signs can describe the benefits of riparian areas and describe the wildlife habitat areas created.
Vegetated Swale- a broad, shallow channel densely planted with a variety of trees, shrubs, and/or grasses. Vegetative swales should be promoted in lieu of storm piping to convey stormwater naturally, promoting infiltration, reducing runoff volume, and filtering pollutants.
How can you apply this in your park? A vegetated swale is an economical alternative to storm piping and may be constructed between a street, parking lot or commercial/industrial area and the park to provide a natural stormwater infiltration area. The park can become a solution to an urban stormwater issue.
Naturalized Infiltration Basin- an earthen structure constructed either by impoundment of a natural depression or excavation of existing soil that provides temporary storage and infiltration of stormwater runoff.
How can you apply this in your park? Existing and new stormwater management basins can be naturalized with native plantings to aid in faster infiltration and to provide wildlife habitat. Basins can be planted with native wildflowers and warm season grasses that are attractive and low maintenance.
Floodplain and Wetland Restoration- tries to mimic the interaction of groundwater, stream base flow, and vegetative root systems- key components of a stream corridor under pre-settlement (pre-1600s) conditions. The interaction among these elements provides multiple benefits, including the filtering of sediments and nutrients through retention of frequent high flows on the floodplain, removal of nitrates from groundwater, reduction of peak flow rates, groundwater recharge/infiltration, reduced erosion, control non native invasive species, and an increase of storage and reduction of flood elevations during higher flows.
How can you apply this in your park? Floodplains should remain natural without constructed facilities; however low-impact accessible paths may be included to invite park visitors to walk among native vegetation and view wildlife. Existing wetland should be protected and restored to enhance their ecological benefits such as increasing water quality, reducing stormwater impacts, and providing critical habitat for a variety of species. Boardwalks and viewing decks can provide access to wetland areas for environmental education. Educational signage can be installed to teach park visitors the critical role floodplains and wetlands play in the environment.
Reforestation- replant the site with trees.
How can you apply this in your park? Reforestation can occur in both natural areas and developed areas of a park. Riparian corridors, floodplains, wetlands, meadows, and forest edges can all benefit from reforestation. Reforestation and planting of trees near picnic areas, pavilions, spectator areas, playgrounds, benches, trails, and other built features will enhance the environment, provide shade, and create a sense of place within a park.
Extensive Green Roof- the most popular green roof for smaller structures and existing structures. Its lightweight attributes minimize the amount of structural changes needed to create it.
How can you apply this in your park? Extensive green roofs may be constructed on park kiosks, pavilions, environmental education centers, sheds and community recreation centers.
Warm Season Meadows- conversion of a turf area into a meadow. Native species should be selected for their minimum need of fertilizers, herbicides and pesticides. Minimize mowing to two times per year.
How can you apply this in your park? Meadows can be integrated into most park sites; particularly along riparian corridors and, forest edges and within un-programmed open space. Meadows diversify the land cover; attract butterflies, birds, and wildlife; and reduce on-going maintenance costs associated with mowing. Trails can be created through the wildflower and/or warm season grass meadow and bluebird boxes can be put up to create wildlife viewing opportunities. Educational signage can be installed to present the environmental and ecological benefits meadows provide vs. turf.
Runoff Capture and Reuse- encompasses a wide variety of water storage techniques designed to “capture” precipitation, hold it for a period of time, and reuse it. These storage techniques may include cisterns, underground tanks, above-ground vertical storage tanks, rain barrels or other systems.
How can you apply this in your park? Rain barrels and cisterns can be used in parks to capture roof runoff from pavilions, environmental education centers or community recreation centers to then be used to irrigate gardens and water plants, flush toilets, storage for firefighting needs, etc.
You can find more information about Stormwater BMPs in the PA Department of Environmental Protection Stormwater BMP Manual here.
Sometimes it’s hard to convince people that more trees are good or that the extra cost for installing pervious paving can go a long way later. The good news is that the Federal, State, and local governments are starting to recognize the importance of green infrastructure in protecting our health, safety, and welfare in addition to future cost savings and improving the environment.
For example, the Borough of Etna, Pennsylvania has had its fair share of flooding problems. Located in the flood plain where Pine Creek enters the Allegheny River, Etna received millions of dollars of flood damage during the heavy rains of Hurricane Ivan in 2004. Even during lesser storms, Etna is prone to flooding. In order to help solve this problem, the Borough has recently secured a state grant plus some of its own money to install permeable sidewalks and rain gardens. Check out this article for more information.
Want to know the economic value of green infrastructure’s benefits for your community? The Center for Neighborhood Technology (CNT) and American Rivers have released a guide that places an economic value on the numerous benefits provided by green infrastructure. Download “The Value of Green Infrastructure: A Guide to Recognizing its Economic, Social, and Environmental Benefits” here.
When you think of infrastructure, you usually think of things like roads, sewer systems, water supply, power grids, etc… It is the basic physical structures needed for a community to enable, sustain, or enhance a certain standard of living for its residents. It enables the buying and selling of goods and services at a more efficient level. Could you imagine your workplace without internet, electricity, or even roads connecting you to your clients?
Wetlands and riparian buffers are green infrastructure.
But what does it mean when “green” is placed in front of the word infrastructure? Green Infrastructure is a concept that can, and should, be applied to all different scales of planning and design. Basically, it includes everything from strategically planned and managed networks of natural lands, to working landscapes, to recreational landscapes, and other open spaces that conserve ecosystem values and functions. In other words, greenways, parks, riparian buffers, wetlands, floodplains, rivers, and even stormwater Best Management Practices such as rain gardens, porous pavements, green roofs, and trees are all part of Green Infrastructure. It recognizes the importance of natural systems and processes within our communities.
Green roofs and rain gardens are green infrastructure.
Why has Green Infrastructure become so important in the last 10 or 20 years? Well, because it is beneficial for the environment, human health, the economy, and our society as a whole. Working with and using natural processes ensures that we’ll have resources for future generations. Stormwater BMPs reduce flooding, pollution, and the strain on our storm sewers. Street trees beautify our neighborhoods, increase property values, reduce the urban heat island, and absorb air pollution and stormwater. Greenways help protect steep hillsides from being developed and eroded, protect wildlife habitat, and offer recreational opportunities. Constructed wetlands not only provide wildlife habitat but filter pollution and even human waste.
So the next time you step outside, try to identify what types of green infrastructure are present and how they help to make your community a better place.
We are proud to highlight this month’s featured project, Whitehall Road Regional Park Master Plan. Located in Centre County, near State College, this future regional park is designed with sustainability and accessibility in mind. The final master plan reflects the following project goals:
Environment – Conserve and enhance natural conditions and features.
Community – Respond to conditions and needs of adjacent and regional community.
Program – Accommodate a logical mix and quantity of park uses.
Economics – Maximize relationship between cost and benefits to community.
Identity – Create a dignified and beautiful park space that improves over time.
The 100-acre park has to meet the growing demand for sports fields, while also accommodating those more interested in passive recreation such as walking, picnicking, and gardening. The master plan includes soccer fields, softball and baseball fields, tennis courts, a football field, a lacrosse field, playgrounds, picnic shelters, walking trails, open space play, a dog park, and community gardens. The existing site is open with dramatic distant views. The park is organized to respond to these conditions by creating a rectilinear pattern of outdoor rooms that connect directly to the adjacent agricultural context. Proposed rows of trees extend the existing forest block to provide a pattern for the roads, walkways and athletic fields.
Proposed stormwater Best Management Practices (BMPs) include rain gardens, permeable paving, vegetated swales, infiltration trenches, vegetated buffer strips, green roofs, and cisterns to name a few. The key is to work with natural ecological processes instead of against them.