Client: Donegal County Council.
Value: €23M

Letterkenny Wastewater Treatment Plant & Sludge Treatement Centre-DBO

This contract provides for the design, build & operate of a new Wastewater Treatment Works at Letterkenny.The wastewater treatment plant at Magheranan is designed for a PE of 40,000 with the capability for expansion to 80,000 PE. The plant is based on conventional activated sludge and comprises of inlet works, carrousel aeration system, settlement tanks and UV disinfection. The Contract also includes a collection and transfer system including 1200mm diameter trunk sewers, 1800mm storm collection sewer as well as a 27m diameter covered storm tank at Ballyraine and a main lift pump station with a pumping capacity of 625l/s.

All sludges from the treatment plant will be transferred to a new 80,000 PE sludge treatment centre at Bunnagee to be constructed under the Contract.The sludge treatment process consists of liquidising and buffer tanks, anaerobic digestion, two stage thickening / dewatering and sludge drying by twin belt dryer.The sludge centre will be powered by electricity generated from the onsite Combined Heat & Power (CHP) plant. The centre also has import facilities for liquid and cake sludge, leachate and septic tank waste as well as an extensive odour control system.

  • The odour system comprises of 2-stage processes comprising of biological & carbon filters.
  • Response Engineering was the lead designer on this scheme and was responsible for all aspects of design including process, civil, mechanical & electrical.
  • The process was designed by Dr. Hans Gethke who has over 30 yrs. experience in treatment plant design.