GRAVETTE — How to fix Gravette’s wastewater treatment system to meet state and federal discharge standards was addressed at a Committee of the Whole City Council meeting last Thursday, February 11, at City Hall.
Representatives from the engineering firm McGoodwin, Williams and Yates (MW&Y) outlined three options which the city may consider. “All three are expensive,” Steve Davis, a representative of the firm, told the group.
Jeff Richards, engineer, used display panels to show the three options which MW&Y says will allow the city to meet the phosphorus and ammonia discharge limits which the present lagoon system is unable to meet.
Two of the options involve utilizing one lagoon of the existing system where wastewater is now treated and is released into Spavinaw Creek. Because Spavinaw is considered a “losing stream”, which disappears underground at some points, the federal limits are most stringent.
Options 1 and 2
Option 1 would utilize one lagoon which will require construction of concrete structures to house treatment and testing facilities. The capital cost of that system is estimated at $7,900,000 with annual operating costs estimated at $350,000.
Option 2 would also utilize one lagoon, but the supporting structureswould be constructed of steel (concrete has an estimated lifespan of about 20 years it was indicated). Capital cost is an estimated $8,000,000 with operating costs of $380,000.
Both options would require management of sewage sludge which involves proper disposal, usually on land or in a landfill.
Third Option
The third option is to build a discharge line to Decatur’s newly constructed sewer system which could handle Gravette’s discharge. The engineers indicated that system, based on population projections, would be an effective alternative for at least 20 or more years. Cost of that option is estimated at $6,600,000 with annual operating costs of $375,000.
At least three lift stations would be required through the hilly terrain between Gravette and Decatur. Also required would be a storage lagoon somewhere near the Decatur plant. There would be no treatment or sewage disposal at the Gravette site other than utilization of our existing lagoon to hold overflow, if such were needed.
Obtaining easements through the hilly terrain from Gravette will be required and it will require meeting all environmental challenges.
A major hurdle will be negotiating a long-term contract acceptable to both cities. The engineers indicated Decatur has initially suggested $2.15 per thousand gallons of treatable wastewater.
Further study of the proposals will be required before any decision is possible but the city is working under a deadline. Its present discharge permit expires on October 31 of this year. An anticipated new permit would then be effective if it is determined the city is making progress toward solving its own problem.
A National Problem
Gravette is not alone since cities throughout the nation are grappling with the more stringent phosphorus and ammonia discharge limits.
The city has been working toward a solution for many months, including retaining the Fayetteville firm to find possible solutions.
Voters last year approved continuance of a three-quarter cent sales tax to help pay for revenue bonds that must be issued to finance the project. It is anticipated that monthly service charges will also have to be addressed to provide adequate funds.
News, Pages 1 on 02/17/2010