REPORT TO THE CITY COUNCIL
FROM: PAUL AMICO, PE, Director
Department of Public Utilities
BY: AHMED ALY, PE, Assistant Director
Department of Public Utilities - Utilities Planning & Engineering
JOSHUA MERTEN, Engineer Il
Department of Public Utilities - Utilities, Planning & Engineering
SUBJECT
Title
Approve a Consultant Services Agreement with Carollo Engineers, Inc., a Delaware Corporation, with a term through June 30, 2029, for an amount not to exceed $855,932, and a contingency amount not to exceed $85,668, for a total contract amount not to exceed $941,600 for the Secondary Treatment Process Rehabilitation Project at the Fresno Clovis Regional Wastewater Reclamation Facility (Bid File No. 120601590) (Council District 3)
Body
RECOMMENDATIONS
Staff recommends that City Council approve a Consultant Services Agreement (Agreement) with Carollo Engineers, Inc., (Consultant), with a term through June 30, 2029, for an amount not to exceed $855,932, and a contingency amount not to exceed $85,668, for a total contract amount not to exceed $941,600 to provide condition assessment and preliminary design services for the Secondary Treatment Process Rehabilitation Project at the Fresno-Clovis Wastewater Reclamation Facility (Project); and authorize the Director of Public Utilities, or designee, to sign the agreement on behalf of the City of Fresno (City).
EXECUTIVE SUMMARY
The Fresno-Clovis Regional Wastewater Reclamation Facility (RWRF) is operated and maintained by the Department of Public Utilities (DPU) and the primary wastewater treatment facility for the City of Fresno (City), a portion of the City of Clovis, and certain Fresno County islands and areas within the City’s sphere of influence. The RWRF treatment process includes primary, secondary, and tertiary treatment, and treated effluent is discharged to percolation ponds for final disposal, groundwater recharge, and reclamation. In December of 2025, the Capital Projects Department completed a high-level condition assessment of the secondary treatment basins and sediment removal tanks in the B Side treatment train. The assessment identified unexpected expansion and cracking of the concrete structures in contact with wastewater as a result of alkali-silica reaction (ASR), a chemical process that causes concrete to expand and lose strength over time.
Additionally, DPU staff observed cracking at the concrete structures and failure of the sludge collection equipment at the C-side secondary treatment basins and sediment removal tanks and have also noted deterioration of the protective coating at the dissolved air flotation Tanks 3 and 4 interior basin walls. DPU seeks to contract with the Consultant to conduct a more detailed condition assessment to provide recommendations to address the B Side findings and rehabilitate C Side and dissolved air flotation Tanks 3 and 4.
BACKGROUND
The RWRF is a secondary biological treatment plant that operates under Wastewater Discharge Requirements (WDR) R5-2018-0080 administered by the Central Valley Regional Water Quality Control Board. The RWRF is permitted to treat up to 91.5 million gallons per day (MGD) of wastewater, and average daily influent flows are currently approximately 54 MGD. The RWRF includes four distinct parallel treatment trains referred to as A Side, B Side, C Side, and the Tertiary Treatment and Disinfection Facility. The B Side and C Side treatment trains are a secondary treatment process that includes biological treatment reactors followed by sedimentation process that recovers and recycles an active biomass for sustained treatment. The biological treatment process utilizes biological reactor tanks, referred to as aeration basins, to mix wastewater and the active biomass with air to consume the waste present in the wastewater. Following treatment in the biological reactor tanks, wastewater is conveyed to the secondary sedimentation basins to settle solids from the wastewater and reclaim the water from the wastewater. A portion of the biological matter within the reactors (sludge), is conveyed to dissolved air flotation tanks (DAFTs) 3 and 4 where suspended solids are concentrated and then conveyed to the on-site digesters further stabilization of the solids. The entire process exposes the treatment reactors and structures to a corrosive environment that requires continuous maintenance and renewal to sustain the treatment performance.
In 2024, staff observed spalling, cracking, staining, and unexpected concrete expansion on the B Side biological reactors and secondary sedimentation basins. In December of 2025, the City commissioned a condition assessment that identified widespread cracking and failed sealants caused by ASR, a chemical process that causes concrete to expand and lose strength over time. At the C Side biological reactors and sedimentation basins, City Staff observed similar but less severe cracking and sealant failures and various sludge collection equipment failures. Lastly, DAFTs 3 and 4 have shown visible deterioration of the existing concrete coating system. Given the outcome of the condition assessment, the City required qualified engineering professionals to further assess and identify appropriate design improvements to the B Side and C Side biological reactors and secondary basins, and DAFTs 3 and 4.
In accordance with Fresno Municipal Code Chapter 4, Article 1 and Administrative Order 6-19, the DPU conducted a Request for Qualifications (RFQ) process to select a consultant to provide the requisite professional services. The RFQ was posted on the City’s Planet Bids website on February 13, 2026. Two (2) Statement of Qualifications (SOQ) were received by the deadline of April 2, 2026. A selection committee consisting of representatives from DPU evaluated the SOQ and upon review of the qualifications and proposed fees, selected Carollo Engineers, Inc. Staff recommends approving a Consultant Services Agreement to the Consultant for a total amount not to exceed $941,600 including an $85,668 contingency.
The City Attorney’s Office has reviewed the proposed agreement and approved as to form. Upon approval by the City Council, the Consultant Services Agreement will be executed by the Director of Public Utilities, or designee.
ENVIRONMENTAL FINDINGS
Staff has reviewed the scope and nature of the Project in accordance with the requirements of CEQA and determined this project is exempt from further analysis under Class 1, Section 15301(b) (existing facilities of publicly owned utilities used to provide sewerage or other public utility services) and (d) (restoration or rehabilitation of deteriorated or damaged structures, facilities, or mechanical equipment to meet current standards of public health and safety). The Notice of Exemption form will be filed upon final approval of the construction project.
LOCAL PREFERENCE
Local preference was not considered because Carollo Engineers, Inc., a local firm per the Fresno Municipal Code, was the only local respondent that had the necessary qualifications, experience, and expertise to complete the proposed project.
FISCAL IMPACT
There is no impact to the General Fund. Funding for this Project has been identified in the Fiscal Year 2026 Capital Improvement Budget within the Wastewater Management Division’s Sewer Enterprise Fund 4500-4501.
Attachments:
Consultant Services Agreement
Environmental Assessment
Notice of Exemption
Vicinity Map
Location Map