By JASON CAMPBELL  

The Bulletin 

The City of Lathrop has taken another step towards achieving the long-awaited goal of being able to discharge tertiary treated wastewater into the San Joaquin River. 

With the approval of the Lathrop City Council, the city is now in a contract with Ascent Environmental to initiate the environmental documentation necessary to acquire the permit to discharge of water from the city’s water treatment plant into the river – a move that could pay sweeping dividends to the city in the future. 

By constructing the necessary infrastructure the city will be in a better position to obtain a National Pollutant Discharge Elimination System permit from the Central Valley Regional Water Quality Control Board, which would eliminate much of the city’s need to dispose of tertiary treated wastewater on spray fields and cut down on the amount of ponds that are necessary to store the water – which can in some instances be cleaner than the water that most people drink. 

The tertiary process typically takes treated wastewater and removes whatever solids still remain before disinfecting it with chlorine and then removing the salt. The end result in a product that in some cases is cleaner than it was when it began and is therefore safe to discharge into the San Joaquin River which eventually flows into the Sacramento-San Joaquin River Delta and out to the San Francisco Bay and ultimately the Pacific Ocean. 

Because Lathrop does not currently have the permit that it is seeking, the tertiary treated wastewater is currently sprayed over rural agricultural fields to filter down into the groundwater supply or stored in ponds.

If Lathrop is able to eliminate the need for sprayfields and holding ponds, that land could ultimately become available for future development. 

The cost of the contract that was approved by the Lathrop City Council on Monday – not to exceed $91,287 – will be paid for by the River Islands development through a funding authorization that has already been executed. The cost will cover the consultant’s work in assisting the city in “developing a detailed project description for the Environmental Impact Report, preparing an Initial Study to focus assessment efforts for the EIR, prepare the notice of preparation, conduct a scoping meeting, and attend meetings with the city and regulatory agencies. 

Once the first phase of work is completed, the consultant would be able to develop a work program for the second phase of the project which will include the lengthy EIR and full completion of the California Environmental Quality Act process for the project. 

As the developer of the city’s largest housing project – which will include more than 10,000 homes once fully completed – River Islands has taken an active role many of the city’s recent infrastructure improvements and long-range planning needs. In addition to funding the majority of the cost of the city’s new wastewater treatment plant – which affords the developer the opportunity to acquire sewer capacity as it becomes available – the development has also played a major role in driving a recycled water program that allows for the use of tertiary treated wastewater on landscaping, saving potable water for drinking purposes.