Aberdeen Area Wastewater Treatment Plant BNR Upgrade
| Aberdeen Area Wastewater Treatment Plant BNR Upgrade | Aberdeen, Maryland |
Contract: $5,918,000
Team Members
Owner: City of Aberdeen, Maryland
Engineer: Stearns and Wheler
General Contractor: Johnston Construction Company
Key Accomplishments:
- The Owner accepted Johnston Construction Company’s recommendation to install stainless steel tanks in lieu of the specified painted carbon steel tanks.
- Johnston Construction Company designed the filter building drain pump system which was incorporated into the project.
- The construction project was substantially complete despite numerous contract additions initiated by the engineer and owner.
- Johnston Construction Company successfully dewatered a large excavation for the in-ground denitrification filters that was located 100 hundred feet from the Chesapeake Bay shoreline and 10 feet below the maximum bay water surface.
Johnston Construction Company provided engineering, construction, and commissioning services for the $5,918,000 lump sum contract on this major BNR upgrade.
This was a major project for a 6.0 MGD BNR upgrade to the Aberdeen Area Wastewater Treatment Plant. The project included headworks distribution chamber modifications, a primary clarifier by-pass with parshall flume structure, primary clarifier modifications, lift pumping station pumps and piping replacement, existing shallow trickling filters conversion into tall aeration tanks with a fine bubble diffused aeration system, a blower building with sound attenuated blowers, instrumentation, insulated piping, a filter building with inground poured-in-place concrete denitrification filters, submersible lift pumps, ultraviolet disinfection, chemical feed system with instrumentation, sludge digester roof demolition, and yard piping.
Major equipment on the project is as follows: two 82 foot diameter 665,000 gallon stainless steel aeration tanks were field erected with walkways and stairways; the aeration equipment manufactured by Enviroquip Symbio provided process treatment for nitrification and denitrification in the aeration tanks; the aeration supply was provided via five centrifugal blowers manufactured by Roots each with 60 HP motors rated at 950 SCFM; a total of four poured-in-place concrete denitrifying sand filters were constructed; and a Trojan four bank ultraviolet disinfection system rated for a 6.0 MGD flow was constructed.
The project was started in July 2004. Final design, construction, and performance testing was completed in January 2006 to meet the Owner’s schedule and regulatory deadlines.