As more intense rainfall causes pollutants to enter the James River through the city of Richmond’s overburdened sewer system, the state has proposed septic tank designs in more rural areas to address another aspect of climate change that impacts pollutant control: rising sea and groundwater levels.
Current rates, which average about $128 for residential customers, will remain unchanged until Dominion’s next rate review next year.
Last month, Virginia began initial discussions on a draft regulation for septic tanks, a common method of treating waste in areas without access to public infrastructure. The draft is part of a 20-year regulatory review set to begin in 2022.
When the regulations were released for review, there were about 1.1 million septic tanks in Virginia.
Most systems are conventional, meaning that wastewater from a residential home is piped into a tank on the property and then filtered through a distribution box that pipes it throughout the property. The wastewater eventually decomposes as it enters the environment.
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There are also alternative systems, which include creating mounds with more soil through which the waste can be filtered or chemical treatments.
Currently, environmental protection measures include setbacks that require conventional systems to be at least 70 feet away from waters containing shellfish. Ideally, these setbacks allow for flooding without overloading the system, so waste does not flow back onto properties or directly into larger waters where shellfish live.
“This is not just a public health problem, it’s an economic one,” said Skip Stiles, former director of the environmental nonprofit Wetlands Watch, in an earlier interview with the Mercury, pointing out how the spread of contaminants could harm aquaculture, or shellfish farming.
The new proposals call on the Virginia Institute of Marine Sciences (VIMS) to create a map of a “critical impact area” that is more vulnerable to sea level rise and groundwater flooding.
Within these areas, conventional systems would be required to maintain a distance of 100 feet from shellfish waters, among other spacing requirements, unless alternative measures can be taken to allow more treatment flexibility in placing the systems on smaller properties.
At last month’s meeting, not a single member of the subgroup, which consisted of state, regional and local officials and environmental groups, objected to the proposals.
However, Stiles, speaking on behalf of Wetlands Watch, raised the question of how to identify critical impact areas as groundwater levels rise, i.e. where groundwater begins to accumulate in deeper parts of the earth.
In some areas, sea level rise and groundwater flooding are causing groundwater levels to rise, but the soil has not yet created conditions to contain the water table.
“We run into the same problem with wetland delineation; it requires flooding of the hydrated soils by vegetation,” Stiles said. “But in some of the newly formed wetlands, the hydrated soils have not yet formed because of rising sea levels. We have some tidal wetlands that are not tidal wetlands because they are waiting for the hydrated soils to form.”
Lance Gregory, director of local water and wastewater services at the Virginia Department of Health, acknowledged that “it would be a very difficult decision to make,” but said he was “open to ideas … that could be consistently implemented.”
The group is expected to meet again on August 22 to continue working on the initial ideas.
Charles Paullin covers energy and the environment for the Virginia Mercury.
