Sluice This Water Plan Past the Experts : A Proposal to Use Treated Sewage to Block Seawater Necessitates Full Scrutiny

“Water, water everywhere, nor any drop to drink” is a familiar line from Coleridge’s “The Ancient Mariner.” Orange County has water, water everywhere offshore, all right, and plenty underground in its vast reservoir, but it is concerned about its drops to drink if the underground supply becomes contaminated by seawater migrating inland. It is considering steps to protect these vital reserves, which is good. However, in its farsighted thinking about how it will accomplish this, it must not put public health at risk.

The Orange County Water District has an interesting plan to inject millions of gallons of undiluted but highly treated sewage into the ground to act as a kind of barrier. It’s a proposed alternative to the current practice of pumping a blend of one-third deep-well water and two-thirds treated waste water underground. This would make a completely treated water barrier to seawater flowing into the county’s ground-water basin, which serves 2 million people. The plan is to use only treated waste water from now on, thus conserving deep-well water.

Water Factory 21, the district’s treatment plant in Fountain Valley, is highly regarded for its treatment processes to remove pollutants from waste water. According to some state officials, this waste water is up to drinking-water standards for toxic pollutants and bacteria.

But state health officials are asking a good question--indeed, the very question the ordinary citizen unschooled in water treatment technology might ask: Will the undiluted treated waste water threaten nearby municipal drinking wells?

For this change in the mix to take place, the regional Santa Ana board of the California Regional Water Quality Control board must approve. It recently held a joint public hearing with state health officials, with a decision expected in the fall. The health department is concerned that small amounts of carbon-based chemicals found in waste water could seep into the basin and eventually contaminate drinking water.

The impulse for caution is right in this situation, however attractive it might seem to recycle waste water as a way of conserving drinking water. While the plan has the enthusiastic support of many state legislators, the concerns of health officials must be fully satisfied first.

It would be absurd to try to prevent one contamination problem by creating another. Avoid the problem before approving the plan by making sure that the treated waste water poses no hazard.