CITY COUNCIL REGULAR MEETING AGENDA PACKET 4-21-26

Page 1 of 3 Item #12 CITY COUNCIL AGENDA REPORT April 21, 2026 Public Works - Utilities Division TITLE: AUTHORIZE THE CITY MANAGER TO ENTER INTO THE THIRD AMENDMENT TO THE PROFESSIONAL SERVICES AGREEMENT WITH CAROLLO ENGINEERS FOR DISINFECTION BYPRODUCT MITIGATION SERVICES IN THE KILKARE SERVICE AREA, INCREASING COMPENSATION BY $75,000 FOR A REVISED NOT-TO-EXCEED AMOUNT OF $1,074,750, AND APPROVE A BUDGET AMENDMENT IN THE WATER CAPITAL FUND SUMMARY The City of Pleasanton has an agreement with Carollo Engineers (Carollo) to support the implementation of its Water System Management Plan (WSMP). The Third Amendment, executed on March 13, 2026, increases the agreement by $75,000, for a not-to-exceed amount of $1,074,750, to provide additional professional services to implement the City’s disinfection byproduct (DBP) mitigation program in the Kilkare service area, including short- term actions and a feasibility study of long-term solutions. Because the work is time-sensitive and required to meet regulatory compliance, staff exercised the emergency procurement procedure approved by the City Council in December 2025. Staff is now requesting City Council ratification of the Third Amendment. RECOMMENDATION 1. Ratify the Third Amendment to the agreement with Carollo Engineers to support implementation of the City’s disinfection byproduct mitigation program. 2. Approve an amendment to increase the budget for the Water Replacement Capital Improvement Program (No. 22190) project by $75,000. BACKGROUND The City purchases treated water from Zone 7 Water Agency (Zone 7) and delivers it to approximately 22,000 customers through its distribution system. Disinfection byproducts (DBPs) can form within the distribution system when disinfectants (primarily chlorine) react with naturally occurring organic material in treated water. Trihalomethanes (TTHMs) and Haloacetic Acids (HAA5) are specific DBPs that the California State Water Resources Control Board Division of Drinking Water (DDW) regulates with Maximum Contaminant Levels (MCLs) of 0.08 mg/L and 0.06 mg/L, respectively. City compliance is demonstrated through testing at eight monitoring locations within the distribution system, where the local running annual average (LRAA) at each monitoring location (calculated quarterly) must remain below the MCLs. In Q2 2025, the City’s LRAA exceeded the MCLs for TTHMs and HAA5 at monitoring location S-31 in the Kilkare 1160 pressure zone (affecting approximately 200 customer services), with calculated values of 0.086 mg/L and 0.074 mg/L, respectively. Upon identifying the Page 229 of 846