COUNTY OF SAN MATEO

Inter-Departmental Correspondence

Department of Public Works

DATE:

February 7, 2003

BOARD MEETING DATE:

February 25, 2003

TO:

Honorable Board of Supervisors

FROM:

Neil R. Cullen, Director of Public Works

SUBJECT:

Increase in Contract Authorization - Alta Vista Drive Reconstruction Project - Country Club Park - South San Francisco Area (County Project No. R6K00 - F36 [366])

Recommendation

Adopt a resolution authorizing an increase of $22,000 in the "Not-To-Exceed" payment limit for contract costs for the Alta Vista Drive Reconstruction Project.

Previous Board Action

Awarded a contract for the Alta Vista Drive Reconstruction Project to Interstate Grading & Paving, Inc. on July 9, 2002.

Key Facts

1.

The original contract had a "not-to-exceed" limit of $573,000 ($506,598 low bid plus $66,402 in contingencies), which we believe would have covered changes in final contract quantities as compared to estimated quantities, as well as extra work normally associated with a road reconstruction contract.

2.

We believe the not-to-exceed limit will be exceeded as a result of overruns in some of the contract bid items necessitated by additional work to adequately conform the new roadway to the existing improvements, and additional work required due to pockets of unsuitable material in roadway subgrade that were not identified by our soils investigations.

Discussion

The work on Alta Vista Drive involved reconstructing an existing narrow road within an already developed neighborhood to the wider street standard. The adjacent homes with their associated improvements are either higher or lower than the roadway area due to the topography of the area, and this complicated some of the conform work that needed to be done to match the new road improvements to the existing improvements. This in turn resulted in overruns in the contract items for roadway excavation, aggregate base, and asphalt concrete associated with making the necessary conforms. In addition, during the cement treating of the native material to provide an adequate foundation for the road, unsuitable sub-grade material was encountered at various locations on Alta Vista Drive, which was not identified during the soil investigation phase. Additional work was required to remove the unstable material and replace it with asphalt concrete to provide a stable roadway section.

Vision Alignment

We believe our recommendation to increase the contract not to exceed amount is consistent with the Shared Commitment to "ensure basic health and safety for all" and Goal Number 7, "maintain and enhance public safety of all residents and visitors," as the extra work associated with the project will improve the overall condition of the road to reduce future maintenance costs and provide for safe conforms between existing and proposed improvements for the benefit of both the adjacent property owners and the public.

Fiscal Impact

The proposed changes will authorize an increase in the original "not-to-exceed" amount from $573,000 to $595,000. The actual costs will be based on final quantities of work for the project and on executed contract change orders.

Sufficient funds are available in the Road Fund to cover the additional cost.

There is no impact to the General Fund.

A form of resolution has been approved by County Counsel.

We will also review future reconstruction projects where there are significant existing improvements or grade differentials to determine how we can best minimize conform problems during construction.