The effect of tidal currents on planned effluent discharge in Puget Sound

Design construction parameters including location for a proposed sewer outfall off Chambers Creek, Puget Sound, Washington were developed by the staff of Northwest Consultant Oceanographers Inc. Applying techniques and computations developed for similar projects, basic working assumptions were developed. These were then tested against a scaled physical model and modified as required. Finally, all assumptions and modifications were evaluated against an on-site field observation project. Currents at various levels were measured by drogues and current meters, one of which was a unique bottom-mounted instrument. Strong current shear at the proposed site assures strong turbulence and mixing. The receiving waters off Chambers Creek are well-able to assimilate both the proposed initial and future effluent loading.