Community Columns

Peripheral canal would improve San Joaquin environment

A peripheral canal would transport water from the Sacramento River around the eastern end of the delta to the state and federal water pumps near Tracy. Construction of the canal would solve many major problems and would be good for Modesto.

Today, water entering the delta from the San Joaquin River is diverted from its route to the ocean, and heads directly to the export pumps. In that water are juvenile salmon trying to get to the ocean from the Tuolumne, Stanislaus, San Joaquin and Merced rivers. Most don't make it; they are pumped down to Southern California or are eaten by predators lurking in front of the pumps.

The young salmon also lack rearing habitat in the south delta because all the wetlands are farmed. These farms pump water and young salmon from the channels without screening the water they divert.

Only 1,158 adult salmon made it up to the rivers of the San Joaquin basin in 2007, down from tens of thousands just several years ago. Some might write this off as a lamentable but relatively unimportant problem. But the Modesto and Turlock irrigation districts are under state and federal obligations to preserve salmon populations in the Tuolumne River. Though they are not responsible for salmon losses in the delta, diminished salmon populations will inevitably result in stricter flow and other regulations affecting the districts' operations.

With a peripheral canal, Sacramento River water would be diverted near Sacramento. The water in the San Joaquin River would resume its natural course to the sea. Funding associated with the canal would allow the creation of new habitat in the south delta for the rearing of young salmon, helping their recovery.

Environmental quality in the delta would actually improve with the canal. In late summer, after the irrigation season, salt water would be allowed to enter delta channels, as it did in previous centuries. This will repress harmful invasive species.

Rock dams placed in the delta to reduce the harmful effects of the pumps will no longer be necessary, improving boating access.

Improved flows in the San Joaquin River to restore fisheries will become possible. This will also help reduce the poor water quality conditions at Stockton.

No roads or waterways will be disrupted by the canal. Either bridges will be built or the canal will be siphoned under waterways such as the San Joaquin River.

If we really want to save the delta, we must stop farming on peat soils. These soils are oxidizing, compacting and blowing away; some islands are now more than 25 feet below sea level. It is no longer possible to prevent flooding of these islands, which will occur because of major storms, earthquakes or sea-level rise. We must start growing wetlands on these islands to restore their elevation, or they will be lost forever.

Meral is the former deputy director of the California Department of Water Resources and serves on many environmental boards, including the Tuolumne Trust and National Wildlife Federation.

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