PUBLIC SERVICE PARK’S BMP FACT SHEET SERIES
RETENTION BASIN
Overview
A retention basin is a constructed pond that maintains a permanent
pool of water. Retention basins are an effective means to reduce storm
water runoff and improve water quality. Wet ponds are applicable for
residential, commercial, and industrial sites, and may provide aesthetic,
habitat, and recreational value.
Description
Retention basins, also called wet detention ponds, or wet ponds are
an effective means of reducing peak flows and providing water quality
treatment. Unlike detention basins, which only store water for a short
period of time, retention ponds hold a permanent pool of water.
Retention basins allow for sedimentation to remove particulates,
organic matter, and metals. Additionally, ponds support the biological
uptake of dissolved metals and nutrients. Removal efficiencies are
dependent upon the amount of time that the runoff remains in the pond,
but generally two-thirds of the pollutants are removed in the first 24
hours.
Retention basins can support aquatic ecosystems, provide habitat, and
enhance the aesthetics of a property.
Benefits
• Improves water quality
• Reduces sediment, solids, and metals
• Reduces storm water runoff volume
• Reduces peak storm water runoff rates
• Aesthetically pleasing
• Provides wildlife habitat
Design & Siting Considerations
• To maintain proper pool elevations, contributing
drainage area should be at least 10 acres.
• Can require a large land area.
• Cannot be placed on steep or unstable slopes.
• Should have a sediment forebay or equivalent
pretreatment.
• Design must ensure proper depth to avoid the
accumulation of pollutants.
• The release of trapped pollutants has a greater
capability if the pond is not designed properly.
• Proper lining must be installed.
Maintenance
• Inspect annually.
• Mow as necessary.
• Debris and litter removal as necessary.
• Clean out the basin before it becomes more than
1/3 full of sediment.
• Control algae blooms.
Outdoor Classroom
Cost Considerations
Costs for retention basins will vary due to factors such
as the value of the land, size, and complexity of the
basin design.
Retention Pond
Wetland
Links
• SD1 BMP Manual
http://www.sd1.org/resourcehandler.aspx?id=261
• Storm Water Manager’s Resource Center
www.stormwatercenter.net
• U.S. Environmental Protection Agency Technology Fact Sheets
www.epa.gov/owmitnet/mtb/wetdtnpn.pdf
• Center for Stormwater Technology and Stormwater Benefits
www.unh.edu/erg/cstev/fact_sheets/index.htm
SD1 • 1045 Eaton Drive, Ft. Wright, KY 41017 • Ph 859-578-7450
For more information or a tour of Public Service Park, call the storm water hotline at 859-578-6745.
Public Service Park RETENTION BASIN Details
The retention basin is a central feature of SD1’s Public
Service ParkSTORAGE
and includesAREA
informational signage on animal and plant species supported by the wet pond. The retenMATERIAL
tion basin receives storm water runoff from the wetland, adjacent paved areas, and surrounding gardens. The basin is approximately 140 feet by 50 feet, and has a maximum
depth of eight feet. It has approximately 14,000 cubic feet of storm water storage capacity above the normal pond level. The basin was designed14
with an aerator that provides
the necessary amount of oxygen to the water. In addition, some of the retention basin’s water is used to irrigate nearby landscaped areas.
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P U B L I C S E R V I C E PA R K
BANKLICK CREEK
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MATERIAL STORAGE AREA
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COLLECTION SYSTEM
BARN
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BUILDING
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EATON DRIV E
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Vegetated Roof
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Vegetated Swale
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Permeable Asphalt
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Underground Detention
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Wetland
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Biofiltration Swale
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Retention Pond
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Permeable Pavers
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Permeable Concrete
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LA RAGE
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ADMINISTRATION
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LA UMP
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Vegetated Roof
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Runoff Surfaces
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Step Pools
Outdoor Classroom
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Oil/Water Separator
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Upper Trail
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Detention
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Storm Water
Detention Pond
Lower Trail
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Cistern
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Urban Forest
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Creek Overlooks
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Biofiltration Swale
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