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BACKGROUND The 2017/18 Capital Improvement Program budgeted $200,000 in CIP No. 17135, Bi- Annual Hydrant Lateral Replacement. The justification of the project states the funding is needed to repair fire hydrants and fire hydrant laterals that are damaged or are otherwise identified as needing repair over the two year budget period. However there has been a significant and unusual amount of earth movement in the Hacienda Business Park, particularly along West Las Positas Boulevard. This has caused a significant number of fire hydrant laterals to break, resulting in the hydrants being removed from service. This project replaces those fire hydrant laterals, and also pre- emptively replaces some fire hydrant laterals before they also break. The fire hydrant lateral replacement accounts for approximately $500,000 of the $850,000 low bid. The second component of this project involves replacing control valves and other appurtenances, such as end of pipe blow-off valves that are used for flushing to ensure water quality. These items are being replaced as part of a preventative maintenance program in areas where resurfacing and slurry seal projects are planned in the near future. Many of the pipes and valves are old and experiencing corrosion. The replacements are being done before the upcoming roadwork, not only to avoid needing to dig into a newly paved street in the near future, but to avoid breakage that could occur while the roadwork is being accomplished. The specific locations were selected from the priority list developed by the Utility Division, in conjunction with a list of roadways identified for the 2018 resurfacing and slurry seal projects. DISCUSSION The broken fire hydrant laterals in the Hacienda Business Park, again mostly along West Las Positas, are caused by a combination of two factors; earth movement and the lateral pipeline material. This earth movement is associated with the clay soil in the area and the recent drought. When clay dries, it consolidates. The earth movement is in the upper five to ten feet as the soil column has dried and consolidated throughout the recent drought. When driving on West Las Positas, fairly significant differential settlement over a relatively small area is visible. The water pipeline mains in the area are constructed of ductile iron, while the fire hydrant laterals are asbestos cement (AC) pipe. The relatively flexible ductile iron main pipelines can accommodate the earth movement, although they are susceptible to corrosion. The relatively rigid and brittle AC laterals cannot accommodate the earth movement, but when in stable soil can last for considerably longer than ductile iron as AC does not deteriorate due to corrosion. The laterals are being replaced with Polyvinyl Chloride pipe (PVC). PVC pipe is relatively flexible, and it is not susceptible to corrosion. Engineering and Operation Services staff have been working closely on developing the scope of work for this project and determining the source of funds to construct the project. Staff has determined that the fire hydrant lateral replacement and the control valve and appurtenance work is a higher priority than other work included in the Capital Improvement Plan funded with water enterprise funds. For that reason, staff is recommending the transfer of funds as listed in the recommendation section of this report, taking funds from lower priority projects to this higher priority project. Page 2 of 3