Recycled Water at Montecito Sanitary District
Currently, the only recycled water procduced at the District's treatment plant is from it's pilot recycled water facility installed in 2019. The small facility intended for evaluating membrane technologies produces approximately 13,000 gallons per day. While it may not be much compared to the amount of water being treated to secondary standards, disfinfected and discharged through the ocean outfall, a significant portion of the recycled water produced is used to offset the District's potable water demand for onsite treatment plant water and for sewer main cleaning.
2022 Recycled Water Feasibility Study
In September 2021, Montecito Sanitary District and Montecito Water District embarked on a collaborative study to analyze four distinct approaches to optimize the beneficial use of treated wastewater within the Montecito community. The primary objective was to identify the best method of maximizing wastewater reuse capabilities thus producing a new local drought proof water supply for the community and reducing the discharge of treated wastewater to the ocean.
The analysis considered local and regional partnerships, non‐potable and potable reuse alternatives, and various treatment methods and technologies. The four concepts evaluated in the study were:
- Non‐Potable Reuse (NPR) – local project producing tertiary quality water for irrigation of large commercial and institutional landscapes in Montecito.
- Indirect Potable Reuse (IPR) – regional project involving a partnership with neighboring special district(s) and the use of the Carpinteria Groundwater Basin
- Direct Potable Reuse (DPR) – local project in Montecito utilizing raw water augmentation at the Montecito Water District water treatment facility.
- Direct Potable Reuse (DPR) - regional project involving a partnership with the City of Santa Barbara and raw water augmentation at the City’s regional water treatment facility.
The study, conducted by Carollo Engineers, comprises of an executive summary and nine (9) technical memorandums (tech memos) to document the analysis and findings.
The excutive summary provides an overview of the evaluation of the four alternatives and a discussion of the selection criteria including costs.
Executive Summary_Enhanced Recyled Water Feasibility Study.pdfTM1 reviews current and anticipated wastewater flows to establish relevant flows for facility sizing. It also evaluated the minimum flow required to keep the outfall operational based on the National Pollutant Discharge Elimination System (NPDES) permit for effluent discharge.
TM01 - MSD Flow and NPDESB Permit Analysis.pdfTM2 reviews historical wastewater flows for both Carpinteria Sanitary District and Santa Barbara to establish available capacity to accept raw wastewater from MSD.
TM02 - CSD AND Santa Barbara WRP Capacity.pdfTM3 presents condition assessment results from an onsite assessment at the MSD WWTP. Structural, electrical, and process engineers, working with MSD engineering and operations staff, determined the current condition of assets at the WWTP to support this project.
TM03 - MSD Treatment Plant Condition Assessment.pdfTM4 provides a description of the existing MSD WWTP, an evaluation of the WWTP process
performance, and a capacity assessment of the WWTP.
TM5 used results from the condition assessment (TM 3) and the performance and capacity evaluation (TM 4) to develop a prioritized capital improvement plan and operating costs for MSD over the
next 30 years.
TM6 evaluates the implementation of an MBR treatment system, which is a biological wastewater treatment process that can replace conventional activated sludge (CAS) and secondary clarification in a smaller footprint and produce consistent, high‐quality effluent. This TM evaluates two alternatives to replacing MSD’s existing secondary treatment facilities: constructing a new MBR facility on undeveloped land, commonly referred as “greenfield” (Alternative 1), or constructing a new MBR facility via retrofitting the existing secondary process infrastructure (Alternative 2).
TM06 - Cost for MBR Construction and 30-yr Operations.pdfTM7 reviews MSD's historical O&G data and discusses primary and secondary dissolved air floatation (DAF) process for O&G removal.
TM07 - Oil and Grease Treament at MSD.pdfTM8 evaluated potential treatment trains for all four reuse project concepts.
TM08 - Recycled Water Treatment Options at MSD.pdfTM9 developed distributed infrastructure alternatives for all reuse project concepts and analyzed key infrastructure components include pipelines, pump stations, storage, and various pipeline crossings (highway, railroad, and creek) necesary for each project concept. This TM also examined the potential NPR opportunities through engagement with potential customers.
TM09 - Infrastructure Analysis.pdf
To download full report as a single file, use the link below:
MWD & MSD Enhanced Recycled Water Feasiblity Study - Full Report.pdf