Tetra Tech provided design, build, and operation services for three renewable natural gas (RNG) projects at the Los Angeles County Sanitation Districts’ (LACSD) A.K. Warren Water Resource Facility.
Tetra Tech originally collaborated with Unison Solutions to design and construct the initial biogas conditioning system using a BioCNG™ system to process approximately 400 standard cubic feet per minute (SCFM) of biogas from the facility’s anaerobic digesters. The system, BCS-1, is producing approximately 2,000 gasoline gallon equivalents (GGE) per day of RNG for direct use in a compressed natural gas (CNG) fueling station. After it began operations, LACSD realized there was not enough RNG storage capacity to keep up with CNG fueling station demand.
Benefits
- Beneficially uses excess biogas, lowers greenhouse gas emissions, and reduces flaring
- BCS-1 has provided nearly 14 million standard cubic feet of RNG to the CNG fueling station
- BCS-1 produces RNG that has an average methane content of more than 98 percent
- With the addition of BCS-2, raw biogas conditioning will increase from 400 to 1,440 SCFM
Based on the success of BCS-1, LACSD selected Tetra Tech for the design and construction of necessary storage modification that will add capacity. First, we added a second 30,000-gallon RNG storage tank and a booster compressor to allow for storage at a higher pressure than BCS-1. Tetra Tech was then selected to design, build, and operate BCS-2, a triple pass BioCNG system capable of processing 1,440 SCFM of biogas to produce approximately 10,000 GGE per day of RNG, which will be delivered to the Southern California Gas Company’s natural gas grid or the existing CNG fueling station.
BCS Storage Modification Project construction was completed in March 2025. BCS-2 is currently in the permitting phase and expected to be operational by the end of 2026.
We appreciate the successful collaboration with Tetra Tech over the past five years in biogas conditioning systems. These projects help LACSD maximize the use of renewable assets and fulfill our mission of converting waste into resources.
