Memorandum 16-049 Storm Drain Slip Lining Design Costs

Memorandum 16-049

To:                       Katie Koester, City Manager

From:                  Carey Meyer, Public Works Director

Date:                   March 9, 2016

Subject:             Expenditure Authorization

Storm Drain Slip Lining Design

This winter, storm drain piping in Bunnell Avenue and Main Street failed creating “sinkholes” that undermined pavement and threatened the safety of the motoring public. Upon investigation, it has become clear that much of the City’s storm drain system installed in the 1980’s has deteriorated to the point that replacement is necessary.  See attached map showing the location of the subject storm drain system.

Public Works believes that the most cost effective method of repairing these storm drains is to slip-line them (similar to what was done on the sanitary sewer system a few years ago). This method of replacement can be accomplished without removal of surface improvements, has minimum impacts to the traveling public, and has proven to be the most cost effective way of replacing underground piping.  Public Works proposes to utilize the same engineering firm that completed the previous slip-lining improvements in Homer – Stephl Engineering of Anchorage, Alaska, and will request permission to issue a sole-source contract. Public Works proposes to utilize HART funds to compete design and construction efforts.

Project design costs are summarized below:

               Site Visit and Inspection of existing storm drains     $  14,500

Prepare preliminary design and cost estimate          $  24,500

               Prepare final plans and bid documents                         $  41,000

               Contingency (10%)                                                                  $    9,000

               Total Project Design Costs                                                   $  89,000

Once construction costs have been determined, Public Works will request City Council appropriation of construction funds.

Recommendation:

City Council pass an ordinance amending the FY 2016 Operating Budget by appropriating funds in the amount of  $89,000 from the Homer Accelerated Roads and Trails (HART) Program to complete the design of the Homer Storm Drain Rehabilitation Project and Authorizing the City Manager to execute all appropriate documents. (Fiscal Note - 456-0380)