Loudoun Water releases pipeline, filtration study for Raspberry Falls
Monday, Aug. 22 by Crystal Owens | 3 comments | Email this story 2Share
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Loudoun Water on Monday released the results of a study aimed at providing solutions to water problems a community north of Leesburg has faced for years.
The study, conducted by Hazen and Sawyer, a New York City environmental engineering firm, looked at water treatment and central water pipeline options for Raspberry Falls, a community of about 250 homes off of U.S. 15 that operates on a communal well system.
They found that should Loudoun County Supervisors decide to allow a water pipeline extension to Raspberry Falls from the Town of Leesburg, a connection from U.S. 15 to Tuscarora High School would be the easiest route to take.
The project would cost $7.5 million to build and the Town of Leesburg would pay $418,000 in annual operating costs, according to the study.
The Town of Leesburg was consulted for the study, according to Dale Hammes, general manager for Loudoun Water.
A pipeline extension would take at least two years to complete, the study said, including garnering Loudoun Board of Supervisors’ approval, easement acquisition, design and permitting and one year of construction time.
Treatment options
Should Loudoun County leaders decide to stay with the current communal well system in Raspberry Falls, the study found that membrane filtration is the best way to treat the water.
Membrane filtration is a process that is used to separate particles from a liquid. No pretreatment chemicals are needed in the process, the study found.
It would cost $4 million to implement the system in Raspberry Falls with $67,000 in annual operating costs. The current annual operating cost for Raspberry Falls’ well system is $50,000.
A membrane filtration system to serve both Raspberry Falls and nearby Selma Estates would cost $8 million to construct and carries an estimated annual operating cost of $217,000, the study said.
Selma Estates also operates on a communal well and serves as an emergency system for Raspberry Falls.
In Virginia, there are about 32 permitted membrane filtration systems serving communal wells systems, the study said.
A well in Selma Estates is being tested by the state Department of Health for a groundwater under the influence of surface water status or GUDI.
That determination could take up to 20 weeks and is not retroactive, according to Mike McGill, spokesman for Loudoun Water.
A board request
Loudoun Water agreed to study a central pipeline option for Raspberry Falls in January after a county Board of Supervisors’ request.
The Jan. 4 vote was in response to requests from residents of the community who were upset that a study Loudoun Water had agreed to conduct in December on adding micro-filtration to the Raspberry Falls system and connecting the community to nearby Selma Estates’ communal wells didn’t include a look at providing the subdivision with a central water source.
If Loudoun supervisors want a central pipeline built to Raspberry Falls, they will need to vote to change the county’s general plan. The general plan currently does not allow such utilities in the Raspberry Falls area, which is considered rural.
Raspberry Falls residents get water from two communal wells. However the community’s main well was permanently shut down Nov. 16 by Loudoun Water after the state Department of Health determined its groundwater source to be under the direct influence of surface water, or GUDI.
A water source is determined to be GUDI if more than 10 percent of total coliform numbers exceed 100 cfu/100 mL.
Six months of testing on untreated water in the Raspberry Falls well determined 12 percent of samples exceeded that threshold, according to a notice of violation to Loudoun Water.
A new well has since been put online. However, that well was shut down for two days recently when turbidity – dirt or sediment – was found in the water.
Raspberry Falls sits on a Limestone Overlay District, and surface water can easily drain downward through joints in the rock, making direct contact with the groundwater serving residents. Surface water generally doesn’t directly intermingle with groundwater resources because soil acts as a natural filtration to remove contaminants.
Many residents of the Raspberry Falls community fear that the karst, or limestone-terrain geology is affecting their water and their health.
Over the years, Loudoun Water has conducted tests on the water system and treats it with chlorine.
Officials with Loudoun Water say there’s never been any evidence of problems with the treated water that enters residents’ homes.