Don’t build wastewater plants until they’re needed

The State Water Resources Control Board is reconsidering the state’s water supply and conservation regulations. Meanwhile, the Sustainable Groundwater Management Act of 2014 is being implemented and Valley cities are updating their pre-drought 2010 Urban Water Management Plans.

This convergence of state, regional and local regulatory regimes provides an opportunity to address urban water reuse in the city of Merced and other Valley communities.

The California Water Code mandates reuse of tertiary treated wastewater by urban communities within their jurisdiction. Reuse of tertiary wastewater from decentralized treatment facilities is defined by the state as a “beneficial use” of water.

Civil engineering consultants in the Bay Area and the San Joaquin Valley already have the knowledge and technology to design and build specially engineered tertiary wastewater treatment systems to serve new housing development or retrofit infill development.

The UC Merced engineering department has the expertise and research resources to assist in the application and improvement of thistechnology for Merced and the rest of the Valley. If implemented, this technology can reduce the demand for potable urban water by almost 30 percent.

Similarly, financing for decentralized tertiary wastewater systems is available. Community Facility District financing for public police, fire safety services and infrastructure for public utilities is commonly used throughout the state. Public finance consultants are familiar with this financing; and, following the repeal of redevelopment agency statutes, new financing options are being created with new legislation surely to follow.

There are numerous financial and environmental benefits of specially engineered community wastewater treatment facilities.

First, using small-scale wastewater treatment systems allows a local government to avoid building excess treatment capacity and incurring the debt to pay for it. This reduces the desire to build treatment facilities that are oversized in anticipation of future growth.

Second, the use of small-scale community wastewater treatment facilities avoids having to speculate about how fast a city will grow. This allows local governments to respond more accurately to real growth as it occurs.

The failure to use small-scale wastewater facilities imposes an unnecessary financial burden on existing local taxpayers and water users. Currently, they pay for the overbuilt (and unused) capacity that doesn’t benefit them. They don’t need it and will never use it, but are asked to pay for it. Using tertiary treated wastewater from small-scale decentralized facilities avoids the cost of having to construct and operate unnecessary water conveyance facilities to return the treated wastewater to the users for reuse on site.

The environmental benefits of small-scale wastewater treatment facilities include reuse of urban treated wastewater closer to the original user, as required by statute; this also reduces the total amount of groundwater used.

These systems can be used for both new development and infill growth, without expanding or surcharging the existing centralized wastewater treatment facilities. Fourth, directly charging residents of the new growth or infill development for the cost of their own wastewater treatment facilities and operating expenses will make these residents more aware of their own water use, so they might reduce the use of treated potable water supplies. Finally, the use of small-scale decentralized wastewater treatment facilities will reduce demand per capita on groundwater supplies.

The current paradigm of building hugely expensive, large-scale centralized wastewater treatment facilities should be re-examined in the light of currently available wastewater treatment technology and financing options.

Gov. Jerry Brown’s administration should aggressively pursue “improved urban conservation” by permitting developers to use state-of-the-art small-scale decentralized tertiary wastewater systems for new development. Implementation of this alternative can be expedited by executive action. This strategy will save money for local ratepayers and will protect environmental resources and comply with the state’s “beneficial use” policy that mandates using recycled tertiary treated urban wastewater.

This story was originally published May 19, 2016 at 3:43 PM with the headline "Don’t build wastewater plants until they’re needed."