Bracewell Engineering, Inc. designed improvements to 5 existing lift stations to convert them from septic effluent pump stations to solids handling pump stations and designed a new solids handling dual stage pump station with a discharge head of 280 ft. These pump stations then discharged to a new advanced treatment plant also designed by BEI consisting of screening, flow equalization, and a pre-engineered membrane bioreactor (MBR) capable of treating wastewater to less than 5 parts per million of suspended solids. In addition, the MBR system incorporated anoxic treatment for removal of ammonia nitrogen to less than one part per million. The system provides the highest quality treated wastewater available, exceeding all regulatory requirements. This new treatment plant also includes treated effluent storage, an effluent pump station to discharge to a drip irrigation system, and an emergency generator for back-up power.

BEI provided sanitary engineering services to a developer in San Joaquin County to design a wastewater treatment plant for the Oakwood Lakes housing development. The design flows were an average dry weather flow of 160,000 gallons per day (gpd) and a peak flow of 200,000 gpd. The treatment plant components consisted of a drum screen, sequencing patch reactor (SBR), hypochlorite disinfection, and land disposal. The design incorporated conversion an existing pond system into a pond SBR, a sludge storage pond, and a flow equalization pond. The treated effluent was pumped to an infiltration system consisting of disposal ponds and subsurface drip irrigation.

BEI provided sanitary engineering services to San Benito County to upgrade a treatment plant to meet Title 22 for reclamation of domestic wastewater for irrigation of a soccer field. The design flows were an average dry weather flow of 42,000 gallons per day (gpd) and a peak flow of 60,000 gpd. The treatment plant modifications consisted of a wasting system to reduce the effluent turbidity from the sequencing batch reactors to Title 22 levels, modifications to the filters to meet Title 22 requirements for turbidity and automatic operation, and installation of metering and controls to meet Title 22 requirements for alarms and automatic shut down. The treated effluent is used to irrigate a soccer field in the Rancho Larios subdivision.

BEI provided sanitary engineering services to a the Pride of San Juan in San Benito County to design a treatment system to reclaim their process wash water for irrigation. The design flow was 150,000 gallons per day. The treatment system components consisted of a grit separator, sand filters, two pump stations, a treated water storage pond, and interconnecting piping and valves. The reclaimed water was pumped to an irrigation system to water vegetable fields.

BEI provided sanitary engineering services to Sonoma County to design a wastewater treatment plant for the City of Monte Rio. The design flows were an average dry weather flow of 100,000 gallons per day (gpd) and a peak flow of 140,000 gpd. The treatment plant components consisted of a drum screen, sequencing patch reactor, sand filters, UV disinfection, and sludge bagging. The treatment system was designed to fit into a building constructed to look like a barn. The treated effluent was pumped to an infiltration system consisting of trenches and subsurface drip irrigation.

The City of Auburn has a 1.67 MGD activated sludge oxidation ditch treatment plant with wet weather storage and treatment ponds and a wastewater collection system with 12 lift stations. BEI has been consulting with the City in improving the compliance record at the wastewater treatment plant, improving the reliability and fail-safety of the lift stations, implementing the City’s pretreatment program and locating the sources of high coliform counts in the Auburn Ravine drainage basin. In addition, BEI successfully assisted the City in defending against a citizen lawsuit directed against the treatment plant’s compliance record and assisted the City in negotiating a new NPDES discharge permit. The new permit allowed the City to proceed with implementation of a much more cost-effective treatment plant improvement program than would otherwise have been allowed. BEI prepared the facilities plan addendum, design drawings and specifications, and office and field engineering services during construction for implementation of this project. The project consisted of installing a new influent headworks with a new screening system, upgrading one of the ponds to full secondary treatment to be operated in parallel or series with the oxidation ditch, optimizing wet weather storage in the ponds, and converting the existing chlorine disinfection system to ultraviolet disinfection to enhance protection of the environment, plus miscellaneous other plant renovation projects. The project was financed through the State’s Revolving Loan Fund.

The City of Hollister had a pond treatment facility followed by land disposal. BEI’s project work included: the design of the original sewer outfall, the treatment plant, and the land disposal system; the preparation of a master plan for expansion of the treatment plant and sewer system; design and construction of treatment plant renovations; and design and construction of the expansion of the land disposal system. Additional project work has included several evaluations of the treatment plant’s capacity, reports on the impact of industrial wastes, reports on the capacity of the plant, micro computerization of the city’s public works data base (treatment plant operations data and sewer system model), and new revenue studies for the water and sewage systems.

A complete wastewater collection, treatment, and disposal system was planned, designed, and built for the Napa River Reclamation District. The project involved review of bid documents, construction engineering and inspection services, as-builts, an O&M manual, sewer use ordinances, and a revenue program. The facilities constructed include community septic tanks, low pressure sewer lines, and a mound disposal system. The leachate from the mound system was collected and pumped to ponds which are designed to provide waterfowl refuge. The wastewater will ultimately be disposed of by evapo-transpiration from the mound system and by discharge to marshland during wet weather. The system has been in operation for over 10 years and has proved to be highly cost-effective and reliable.

BEI studied and designed a shallow sand trench disposal system to maximize the effluent disposal capacity from the pond treatment system serving the Oceana Marin development. The system included a dosing siphon and a series of eight trenches following the contours of a hillside below the pond. Valving was provided to allow dosing to any one of the trenches individually and to isolate either half of any trench. Following installation, BEI assisted the district in testing to establish the significantly increased capacity of the system and to obtain approval of that capacity from the North Coast Regional Water Quality Control Board.