Fresno Tertiary Treatment And Disinfection Facility — Fresno, CA
Client
- City of Fresno Department of Public Works
Project Value 
$33 Million
Market
Water And Wastewater
Services
Design, Engineering
The City of Fresno relies mainly on groundwater as its primary drinking water source. To conserve valuable drinking water resources, the City will transfer its non-potable water demand for landscape irrigation and commercial and industrial uses to tertiary treated recycled water. In addition, the City plans to maximize the recharge of groundwater with acceptable recycled water quality. The City’s goal is to recycle 25,000 acre-feet per year or more by 2025. Consequently, it embarked on a project to design and construct a tertiary treatment and disinfection facility (TTDF) at the Fresno-Clovis Regional Wastewater Treatment Facility. Also, a new recycled water distribution system, including pipelines, pump stations, and storage reservoirs, will be developed.
TTDF Phasing And Capacity Planning
A phased plan was developed for the 30-million-gallon-per-day (mgd) TTDF. The facility has an initial capacity of 5 mgd in response to the immediate recycled water demands identified in the recycled water master plan. However, it will be expanded to 30 mgd over the years. This expansion will accommodate more users in incremental phases.
Technology Evaluation And TTDF Process Design
We performed a review, screening, and life-cycle cost analysis of various conventional media filtration technologies, microfiltration, and membrane bioreactor (MBR) technology.
MBR was chosen because it produces the highest quality recycled water and is amenable to the denitrification process. This added benefit is essential because nitrogen removal will be a requirement. This will be especially true when the treated effluent is used for groundwater recharge. Design of the MBR system also included a biological treatment train (secondary treatment) upstream of the filtration membranes. Other processes designed as a part of the TTDF include a fine screening facility. Additionally, an MBR process designed around hollowfiber submerged membranes is included. In-pipe ultraviolet (UV) disinfection is also included. Other facilities designed included a blower facility to house scour air blowers for the MBR system. Moreover, electrical components for the MBR and UV systems, and conversion of an existing aeration basin into a recycled water storage tank were designed.
Project Services, Funding Support, And Sustainability Features
Our scope of work included preliminary and detailed design; State Revolving Fund loan and permitting assistance; services during construction, start-up, and commissioning; and participation in stakeholder and public meetings. An additional component of the project involved developing sustainable and green energy alternatives. We provided planning and preliminary design services for a 2 MW solar photovoltaic system at the Fresno/Clovis Regional WRF. The solar photovoltaic system was procured using the design-build delivery method.
