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Title XVI Water Reclamation and Reuse Grants - 2019

California

Padre Dam Municipal Water District, East County Advanced Water Purification 

Facilities Preformed Chloramines Research to Ensure California Toxics Rule 

Compliance 

Reclamation Funding: $45,150 Total Project Cost: $180,603 

Padre Dam Municipal Water District, in San Diego County, California, will partner with regional 

partners to evaluate the use of preformed chloramines to both carry a chloramine residual to prevent 

membrane fouling and to meet the California Toxics Rule requirements for discharge to Lake 

Jennings. Pretreating the advanced water purification facility (AWPF) feed flow with chloramine via 

the industry-standard method would result in the generation of unacceptable levels of 

trihalomethanes. The research involves modification of the District’s existing demonstration AWPF 

for the preformed chloramines method and one year of monitoring to ensure trihalomethane 

concentrations are below detection limits. The results of the field research will feed directly into the 

design and construction of the new full-scale AWPF. 

City of San Diego, Demonstrating Innovative Control Strategies for Reverse Osmosis 

Membrane Degradation and Preserving Water Quality in Potable Reuse Application 

with Optimized Chloramination Strategies 

Reclamation Funding: $155,113 Total Project Cost: $620,451 

The City of San Diego in southern California will research the impacts of elevated bromide levels on 

reverse osmosis (RO) membrane oxidation and compliance with the California Toxics Rule. The 

region has seen increased bromide levels due to an increase in seawater desalination supplies and an 

increase in imported water supplies from the State Water Project rather than the Colorado River. 

The elevated bromide levels are expected to increase the rate of oxidation of RO membranes and 

increase formation of brominated disinfection byproducts. The research will evaluate three control 

strategies that ultimately could reduce the anticipated RO membrane replacement frequency -

lowering operation and maintenance costs. The results of the research will be directly applied to the 

Pure Water San Diego Project, which will be the first surface water augmentation potable reuse 

project in California upon completion. 
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The Metropolitan Water District of Southern California, Demonstration of Pathogen 

Removal through an Alternative Treatment Technology to Treat Non-Nitrified 

Secondary Effluent for Potable Reuse 

Reclamation Funding: $750,000 Total Project Cost: $3,987,785 

The Metropolitan Water District of Southern California and the Sanitation Districts of Los Angeles 

County are exploring the potential of a large-scale Regional Recycled Water Program to beneficially 

reuse water currently discharged to the Pacific Ocean. The facility would use a treatment train 

comprised of a membrane bioreactor (MBR) process, reverse osmosis (RO) and advanced oxidation 

process driven with ultraviolet light (UV). However, there are no operating facilities using an MBRRO-UV treatment train for indirect potable reuse and a primary challenge for implementation is the 

current lack of pathogen reduction credits for MBRs. This project will assess pathogen removal by 

the MBR process to gain pathogen reduction credits and technology acceptance from California 

regulatory authorities for MBR as a key pathogen barrier in a potable reuse treatment train. The 

project will demonstrate that the advanced water treatment processes can achieve the water quality 

and operational goals necessary to develop a regulatory strategy to streamline incorporating MBRs 

into potable reuse applications in California, ultimately facilitating safe and cost-effective expansion 

of recycled water.

Oklahoma

City of Norman, Lake Thunderbird Water Reuse - Field Research Project for Inland 

Indirect Potable Reuse 

Reclamation Funding: $700,109 Total Project Cost: $2,800,435 

The City of Norman, through the Norman Utilities Authority, seeks to advance the first indirect 

potable reuse (IPR) project in Oklahoma by augmenting a Bureau of Reclamation reservoir (Lake 

Thunderbird) with highly treated effluent from the City. The research will be done in collaboration 

with state regulators and entails pilot-scale testing to evaluate the effectiveness of various advanced 

treatment processes at meeting target effluent water quality limits in accordance with newly-released 

IPR requirements in Oklahoma. The research also will determine the suitability of these advanced 

processes for an inland IPR application without the use of high-pressure membranes such as 

nanofiltration or reverse osmosis. The results from this study could impact future potable reuse 

projects across the country by advancing a treatment strategy that does not generate a highconcentrate brine and eliminates challenges associated with its disposal.