Biology Reference
In-Depth Information
still being decided. In the meantime, it offers seasonal wetland habitat and
hosts an antenna array used by pilots to triangulate their position as they
fly into regional airports.
Most of the land north of the highway between the Sonoma Creek and
Napa River bridges is part of state-owned Napa-Sonoma Marsh. These
10,000 acres of old salt ponds came to the people of California via an oil
spill settlement in 1994, and another 1,400 acres of ponds were added in
2003. Among the 12 ponds slated for restoration, Pond 2A proved a simple
one-man job. As the story goes, Carl Wilcox simply chose a good spot on
the levee to blast a hole and “presto,” he created a wetland. But nearly every
other pond was more problematic. Too much salt had built up in the
ponds to permit simple breaching. If flushed out into the Napa River, the
saline slurry would kill fish or violate water-quality standards. One pond
even contained bittern, a byproduct of salt production toxic to fish and
aquatic life unless extremely diluted.
By 2003, the state had come up with a plan for converting three ponds
adjoining the Napa River to tidal marsh and leaving five inner ponds as
the kind of open water favored by diving ducks. During a wet winter in
2006, when sloughs were full of freshwater runoff, managers undertook
“salinity reduction breaches” on the three ponds slated for tidal marsh res-
toration. In the future, urban wastewater from Sonoma County will help
dilute the bittern pond until it can be converted into marsh.
The levee at this former
salt pond near the Napa
River, breached several
years ago as part of a res-
toration project, is now just
visible above the water
line. Such projects form
shallow-water shorebird
habitat at first, then evolve
into vegetated tidal marsh.
(Jude Stalker)
Farther along the highway beyond the state salt ponds and just before
the bridge to Vallejo lies Cullinan Ranch, among the most eastern lands in
the San Pablo Bay wildlife refuge. Soils on the diked ranch lost their origi-
nal wetland sponginess long ago, and now lie five to seven feet below sea
level. Breaching the dikes all at once will quickly immerse the ranch in
three feet of water, and thereby drowning a lot of animals.
