Memorandum 10-36 Soundview/Woodard Creek Sanitary Sewer Repair

MEMORANDUM 10-36

TO: Walt Wrede, City Manager
FROM: Carey Meyer, Public Works Director
DATE: February 3, 2010
RE: Soundview/Woodard Creek Sanitary Sewer Repair Authorization to Complete Design
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In December 2009, the sanitary sewer on Soundview near Woodard Creek plugged. Sewage backed up into the crawlspace of an adjacent residence. When attempts to clean the line with the sewer jet failed, Public Works was forced to excavate and found that the Woodard Creek culvert over the years had settled onto the sanitary sewer main creating a dip in the line. This caused debris, sediment and grease to collect and plug the line. Cold air in the culvert aggravated the situation by freezing the collected material. No sewage reached the creek.

This problem needs to be rectified. Public Works cannot guaranty that an accelerated cleaning regime will keep this problem from occurring again. The best long-term solution is to raise the Woodard Creek culvert so that the low spot in the sewer main can be corrected and the culvert can be insulated from the sewer main.

We propose to design a new creek culvert crossing. We will look at the possibility of installing a bridge similar to the one recently installed across Woodard Creek at Spruceview two blocks downstream from Soundview. The Soundview/Woodard Creek culvert crossing has been the site of flooding problems in the past and a larger hydraulic opening would benefit area residents. A new culvert could cost $100,000; a new bridge could cost $250,000.

The cost to design a new culvert crossing is estimated to be $9,900. With the cost of a design survey and some additional budget to study and design a bridge (if that option is determined to be best); a design budget of $26,000 would be appropriate at this time. The cost of repairing the sewer should be covered by the Sewer Reserve account; the cost of improving the creek crossing should be a HART Fund account expense. We propose that the design cost be split 50/50 between the two funds.

Recommendations: The City Council pass an ordinance authorizing $26,000 for the design of the Soundview Sewer Main Repair/Woodard Creek Crossing Improvement.

Public Works will at the second reading of this ordinance request a resolution approving a contract with Wm. J. Nelson & Associates of Kenai, Alaska in the amount not to exceed $26,000.

Fiscal Note: Sewer Reserves, 256-381 ($13,000); HART Program, 160-771 ($13,000)