Do you live in a development with a pond? Are you in a homeowners association that has responsibility for a pond? Delaware Soil and Water Conservation District is holding a Neighborhood Pond Management Seminar geared for subdivision and condominium residents and homeowners associations. Join us on Thursday, July 27 at the Powell Municipal Building at 47 Hall St. The workshop will be held from 6:30 to 8:30 p.m.
A pond in a subdivision is usually different than the pond built by an individual homeowner who uses his/her pond for recreation and aesthetics. There are two kinds of ponds used in condo sites and subdivisions — detention and retention basins (industry professionals refer to them as basins rather than ponds) — and nearly all of the basins located in subdivisions in Delaware County serve as part of the stormwater infrastructure. This means that managing a homeowner pond is quite different than managing a condo or subdivision basin, even though they make look the same. Our Neighborhood Pond Management Seminar will address the challenges of maintaining condo and subdivision basins long term.
What are detention basins and retention basins? The difference is whether the basin holds a permanent pool of water. A detention basin is considered a “dry” basin, holding water only during storm events and releasing the water slowly in order to reduce the possibility of flooding or erosion downstream. A retention basin retains a permanent pool of water and although it may look like the typical homeowner pond, the retention basin still has some storage capacity and water quality capabilities.
When the basin is first constructed by the developer its purpose is to trap sediment from the construction site. As the homes are built and bare soil is covered with grass, trees, and gardens, the purpose of the basin shifts to capturing the increased runoff from the impervious surfaces in the subdivision — roads, sidewalks, driveways, roofs, and parking areas. An additional purpose of the typical Delaware County condo and subdivision basin is that it serves a water quality purpose as required by the US Environmental Protection Agency under the Clean Water Act, which is to capture the “normal” rainfall runoff and hold the water for a short time. This allows the nonpoint source pollutants carried by the surface runoff to settle out in the basin. What are nonpoint source pollutants? Everything the rainwater picks up on its journey to the basin including roof and asphalt grit, pet waste, grass clippings, leaves, fertilizers, pesticides, and motor oil from driveways, roads, and parking areas would be considered nonpoint source pollution. Holding the surface runoff in the basin creates the opportunity for the pollutants to be assimilated and thereby releasing cleaner water into the storm sewer system and into the nearest stream or river.
Condo and subdivision basins can be challenging since they belong to the development, are often part of the stormwater infrastructure managed by a local government entity, and require maintenance in order to operate effectively. Topics to be covered at the July 27 seminar include fountains and aeration, Canada geese, cattails, algae, structures such as catch basins and surface inlets, and more. The cost to attend is $5 per family and includes a packet of informative handouts. Weather permitting, we will travel from the Powell Municipal Building to two nearby neighborhood basins to discuss the common questions our office receives. A registration form is available by viewing our website at www.delawareswcd.org or calling the office at 740-368-1921. Registration is due by July 25.
Be sure to check out our upcoming educator workshop July 25-26 as well as our Soils and Drainage Clinic on Aug. 3, 2017 — all at www.delawareswcd.org. Our schedule of great events for the Delaware County Fair will be posted soon so keep checking back.
