Look back at the many lagunas of Sonoma County

During Mexican times (early 1800s), laguna was used for a number of places in Sonoma County. While its Spanish meaning varies over a spectrum from seasonal to perennial, and from salt to fresh water, locally the name referred to perennial bodies of fresh water. In other words, “lakes.”

Lagunas de Liwantolyomi was the name for a string of lakes running fourteen miles from Cotati to north of Sebastopol. Today, the lakes are largely gone and we say Laguna de Santa Rosa, as if it were just one. That demotion to the singular hints at the decline of surface water over the over the last two centuries.

In winter, a channel connected the lagunas to the Russian River. In the summer, the channel dried up, but the lagunas persisted. Lake Jonive, the largest, was: “a mile long, 150 feet wide, and from 20 to 30 feet deep, bounded with oaks, willows, etc … is a favorite place for bathing, boating and fishing.”

Tolay Lake, east of Petaluma, was another laguna. At two-thirds of a mile long and a half-mile wide, it’s the “lake” in Lakeville. To the southwest, the Laguna de San Antonio straddled the Marin border. It was two miles long and a half-mile wide, at least after a wet winter. An 1837 map of the Kenwood area shows a laguna of several hundred acres. Today its remnant is known as the Kenwood Marsh.

Mexican maps also show springs labeled posos and ojos de agua — literally “eyes of water.” Jose Altimira, during the 1823 expedition that established the Sonoma Mission, was so impressed by Sonoma Valley’s abundant water, that he described it as un manantial a manantiales — a “fountain or fountains.” Nowadays that observation feels apt in the middle of a wet winter or damp spring. But Altimira was here at the end of June.

Even in those well-watered days, there was seasonal variation. Winter rains dotted the low places with vernal pools and swales. An early map depicts such a 100-acre pool in modern-day Rohnert Park — it was perhaps the biggest one in the county. Yet it didn’t qualify for the title “laguna,” probably because over the summer, all that water seeped or evaporated away, leaving behind an expanse of dry earth.

Tolay Lake also swelled and shrank but was less reliant on rain. Located on an active fault, it’s what’s known as a sag pond. Tectonic activity often brings groundwater to the surface, creating springs. Much of Tolay’s water came from such springs, while a natural dam prevented it from running off.

The liwantolyomi were the people living near the Laguna de Santa Rosa. Liwa is the Miwok word for water, so a rough translation might be “water people,” a good name for a group living by one of the biggest freshwater wetlands in Northern California.

In those days, much of Sonoma County might have been nicknamed “The Land o’ Lakes.” So where have all the lagunas gone? To some degree, they’re still here. The Laguna de Santa Rosa is still considered “a wetland of international importance.” The lagunas have also been turned into reservoirs, drained, channeled off and tapped from below by groundwater wells. In a time of drought, it can seem we’re throwing away wealth that has literally rained from the sky.