ASHLAND — An engineering firm will narrow down a solution to a potentially costly overflow problem at the Ashland Water Treatment Plant to the tune of $202,500.
City council unanimously approved officials to hire Columbus-based Burgess & Nigle on Tuesday.
Although complex, the problem can be boiled down to two simple truths: when it rains hard in Ashland, the water treatment plant's holding basin overflows. And when that happens, the federal Environmental Protection Agency isn't happy.
The city receives a National Pollutant Discharge Elimination System permit from the EPA every five years. When Ashland received the last permit two years ago, there was a condition.
The condition said the city must find a solution to the issue before the next NPDES permit is issued.
The problem, said Mike Hunter, the city's utilities director, is the treatment plant's equalization basin was designed to treat five million gallons of water a day.
Intense downpours in Ashland put a strain on the basin, causing it to overflow in a way that is noncompliant with the EPA, Hunter said.
He said the basin, which is the size of two football fields and 80 feet deep, can handle up to 10 million gallons of water. But anything over that amount is too much.
"Depending on how long this event occurs, how long the impact is to the plant, we have a five million gallon separate holding tank. Once that five million gallon (tank) is eclipsed, there must be an overflow," Hunter said.
He said there have been three such events this year, which is in line with the three to six events that have been happening per year lately.
Hunter said the study should be completed by June 2022.
The comprehensive study will explore options to reduce overflow events or eliminate them altogether, he said.
"We will do something," Hunter said, adding the city must per the EPA. He just doesn't know what, exactly. The study will explore many options.
Some of those options might include building another separate equalization basin or redirecting downspouts so stormwater does not mix with sanitary sewer water, which is the case for many of Ashland's older homes.
"And that is where the big expense will come in, because to correct that will be tens of millions of dollars," Miller said.
Hunter said the EPA will review the study next year, at which point the city will need to decide on a project that could cost up to $30 million.
Mayor Matt Miller said addressing this issue is essentially the city's next phase in its effort to update infrastructure — the first being repaving old streets.
"But what you have to remember is, under every one of those streets is an old sewer line, an old water line and all of them are even older than our city streets," Miller said.