Resolution 3945 - Laserfiche WebLink

Background Pigeon Creek No. 1 is an approximately 1200 acre drainage basin located in Southwest Everett (see figure 1). A drainage basin plan for Pigeon Creek No. 1 was adopted by the Everett City Council on Nov. 9, 1988. The goal of the Pigeon Creek No. 1 Drainage Basin Plan is to improve the water quality and flooding conditions in Pigeon Creek No. 1 so that natural spawning can be restored within the stream. Several structural and non-structural measures are recommended in the plan to help achieve the stated goal. Since adoption of the Pigeon Creek No. 1 Drainage Basin Plan, a regional detention pond, one of the key structural measures has been constructed upstream of Forest Park. The regional detention was constructed in the summer of 1990. The City also retained a contractor in the summer of 1991 to construct a series of log weirs downstream of Mukilteo Boulevard. These log weirs eliminated several fish migration barriers within lower Forest Park. Salmon are now able to spawn within Pigeon Creek No. 1, upstream to Mukilteo Boulevard. Purpose of this Addendum Repair of the culvert under Mukilteo Boulevard is another structural measure recommended in the Pigeon Creek No. 1 Drainage Basin Plan. As discussed in the plan, the downstream end of the culvert is perched six feet above the stream channel. A pipe joint was leaking a few gallons per minute at the time the plan was written. Abrasion of the upstream pipe invert had also exposed reinforcing bars of the concrete culvert. The recommendation in the plan was to repair the leaking joint and exposed reinforcing bars. Replacement of the culvert wasn't recommended. The plan further recommended consideration be given to installation of a series of weirs at the downstream end of the culvert to allow fish migration upstream of Mukilteo Boulevard. The estimated cost of the culvert repair was $20,000. Since adoption of the plan in 1988, conditions at the Mukilteo Boulevard have worsened significantly. Geotechnical investigations indicate an increased rate of water leakage through multiple pipe joints and a creeping of the roadway embankment fill. Construction of a new structurally sound culvert and fishway are proposed at an estimated construction cost of$742,000. The purpose of this addendum is to revise the plan to reflect the significantly increased cost of plan implementation and to ensure that the Mukilteo Boulevard culvert replacement continues to be eligible for state funding. Dh1 KE039BAY(YJ 2/7/94)