Through competitive selection, Washington State's LOTT Alliance chose HDR to design process improvements at the Budd Inlet Wastewater Treatment Plant. The LOTT Alliance provides wastewater treatment and water reuse for the growing communities of Lacey, Olympia, Tumwater and Thurston County.
The Budd Inlet improvement plans covered upgrades for the biological nitrogen removal process and the centrate and chemical feed facilities. Odor control and energy conservation improvements were included as were rehabilitated primary sedimentation facilities. The estimated cost is $35 to $40 million.
LOTT is the only utility, with a nitrogen removal requirement, that is discharging into Puget Sound. The utility is planning to reduce effluent total inorganic nitrogen to 2 mg/l, one of the lowest limits in the country. The project also includes evaluation of alternative carbon sources for nitrogen removal, aeration blower improvements, instrumentation upgrades, electrical system upgrades and site mitigation improvements.
We are using 3-D Building Information Modeling (BIM) design to more efficiently communicate complicated concepts. BIM also effectively arranges complex, expansive plans and allows engineers to avoid costly change orders with integrated planning well before construction documents are issued.
During pre-design, we are conducting technical workshops with the client to make major design decisions, prepare an engineering report and developing drawings 10 to 20 percent complete. Detailed design work on primary sedimentation improvements will follow; and then the activated sludge improvements, outlined in a future design contract, follows that.