The Department of Public Works is in the process of redesigning a dry pond located on City Property at latitude 39.130961 N, and longitude 77.241414 W. The project will involve completing a feasibility study regarding removal of the concrete weir at the downstream side of the project area and replacing 190 ft of linear concrete channel with a wetland complex mimicking nature. The dry pond was originally installed in 1989 and designed to allow for temporary retention of water. Since that time, advanced studies recommend installing wetland complexes to use less concrete. The updated practice will allow the water time to infiltrate into soils and the vegetation will absorb nutrients and pollutants to reduce downstream impacts to water quality. This will help the city reduce its impacts to the larger pollution problems in the Chesapeake Bay.

DESIGN GOALS AND OBJECTIVES

• Remove concrete channel and create a more natural stream/wetland complex
• Conduct feasibility study to remove concrete weir downstream without increasing floodplain on downstream side of current weir
• Improve water quality by encouraging water infiltration rather than runoff.
• Improve aesthetics by removing concrete and planting trees
• Remove invasive species including bamboo on city property
• Plant trees to lower stream water temperature (an anticipated new pollutant for the MS4 permit), and simultaneously increase tree canopy coverage, which is another city goal to meet 40% tree canopy coverage. 
• Decrease area that the city has to mow and maintain

STATUS

By popular vote, the wooded wetland complex, alternative two has been selected. The City will proceed with 30% design to follow the below expected schedule:

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COMMUNITY FEEDBACK

From the community meeting and survey, the following feedback/concerns and priorities were noted:

• Reference for trees -
  Most survey responders commented that trees will not only provide the most benefits for cooling and water treatment but also provide the best aesthetic for the community. (Alternative 2- the wooded wetlands was selected as it had the most trees).

• Concern for tree maintenance - 
  The city will follow a maintenance schedule to protect the trees. If trees on city property need additional care this can be reported to public works at publicworks@gaithersburgmd.gov or calling 301-258-6370. (If there is a large dead tree and is not threatening structures or property, dead trees are great habitat for owls, woodpeckers and bats (who may eat 1,000 mosquitoes per night!)

• Mosquito Management –
  Mosquito management was a concern for most residents.
  
  The City design will deter mosquitoes by keeping water levels low to not allow mosquitos to thrive. Plant species will be selected to attract mosquito predators and/or deter them. Mosquitoes can also breed in rain gutters, and other small areas of pooling water. The best method for deterrence is to set a trap with larvicide such as a mosquito dunk which will kill the larvae, but not harm birds, and other insects.
  
  For more info on mosquito management view the Montgomery County suggestions.

• Bamboo management -
  The City has been granted permission from landowners with bamboo to begin removing the bamboo before construction so it will be well under control prior to any construction.

• Deep water and children’s safety -
  The area will be designed to drain water levels within 72 hours of storm events. Some areas of pooling may exist but they will be shallow and likely have an established plant community versus a true ‘pool’ of water.

• Children’s sledding area - 
  An area on the longest part of the slope can be designed to have other native plants that would allow for children’s sledding.

• Loss of children’s play area -
  The City understand the need for play and will make some design accommodations (such as reserving a sledding hill). However, this is a stormwater facility, not a traditional park area and accommodates a 73 acre drainage area. This facility keeps landowner stormwater fees down, and treats stormwater by removing pollutants so that children downstream of us can also play in the stream or fish safely.

• Concerns on construction management, and tidiness -
  The construction area will be fenced off; designated stockpile areas will be created. Contractors will need to follow standard work hours to prevent excessive disruption. Project manager contacts will be provided to the residents to report anything of concern.

If you have a priority, concern or question please do not hesitate to contact us at stormwater@gaithersburgmd.gov.