RIVER DUNES – A large pond, supposedly designed to hold treated wastewater while it slowly seeps into the ground, is not working properly, which has forced Bay River Metropolitan Sewerage District to quickly jury-rig a fix in order to avoid an embarrassing spill.
Any breech of the ‘infiltration basin,’ which holds millions of gallons, would be particularly troublesome because it is located directly across Orchard Creek Road opposite the entrance to this affluent residential community.
Recent heavy rains have aggravated the problem so that so-called ‘freeboard’ of the basin has shrunk to dangerous dimensions, almost guaranteeing an overflow if an immediate remedy is not implemented.
Ironically, most of the effluent that currently fills the basin is being generated not by River Dunes, but by households in Oriental.
“The majority of the water going in there is from Oriental,” confirmed Ed Riggs Jr., vice chairman of the sewer district. “Those dike walls (of the basin) could be in some serious condition.”
One saving grace: The effluent is of ‘re-use’ quality, the highest standard. The high-tech treatment plant, located on the outskirts of Oriental, was constructed almost two years ago. However, one important – and now embarrassing -- component remains incomplete: yet another infiltration basin.
This one would be designed to receive Oriental’s share of all wastewater generated. In other words, the sewer district would pump to a receiving site close by, not to a pesky pond eight miles away at River Dunes.
Mercifully, that facet of the system remains in limbo.
Now, a good bet is that the entire concept of infiltration in the quirky soils of Pamlico County has become a highly questionable technique – perhaps soon to be relegated to the stockpile of great ideas that never worked.
In a meeting Thursday night, the 11-member board of directors for the sewer district approved a costly emergency plumbing job intended to divert the treated effluent by pumping it miles away to Bayboro – but not before the sewer district’s engineering firm, Cary-based McKim & Creed, received a verbal pummeling.
One board member, George Smith, launched what can only be described as a diatribe.
“It seems to me that we shouldn’t have to pick up any expense,” complained Smith. “McKim & Creed ought to be on the hook. Here we are being forced to ‘Rube Goldberg the system’ and my strong opinion is that they should pay for it.”
In a four-page letter to state regulators dated Dec. 4, Kevin Eberle, McKim & Creed’s lead engineer for the project, seemed to backpedal on the viability of infiltration.
“Basin #3 was one of the first-generation infiltration basins designed in North Carolina,” he wrote. “This early design relied on the premise that the silty sand surficial aquifer was ‘connected’ directly to adjacent tidal creeks; thus allowing water to flow through the aquifer and outlet into the adjacent tidal creeks located several hundred feet from the basin.”
Eberle also cited the hydrology firm, Edwin Andrews and Associates -- commissioned earlier this decade to evaluate the site. The hydrologists ultimately gave the location a thumbs up, a decision which may come back to haunt them.
We (both engineering companies) “have begun preliminary field investigations in an attempt to determine the reason why the basin is not infiltrating at the design infiltration rate,” he wrote.
Eberle went on to propose “some additional tests at the site to confirm whether or not we have correctly diagnosed the problem.”
Rest assured that plenty of back channel negotiations are in the works. The Aquifer Protection section at the Washington Regional Office of the North Carolina Department of Environment and Natural Resources recently ordered Art Hough, Executive Director, of the Bay River Metropolitan Sewerage District to “bring Infiltration Basins 1 and 2 completely online so that their use can be maximized.”
David May, a regional supervisor, has given the sewer district 60 days in which to comply.
The latter two basins are situated near Basin 3. The reverse chronological order is screwy enough. Now observers familiar with the scenario have begun to wonder: Why expect two more to work, when the first one is ready to fail?
“Ed Mitchell (President of River Dunes Corp.) wants to know why the basins are not working,” explained Hough in an understatement. “McKim & Creed knows it is a design problem.”
