Diseños, Penitencia Creek and the Coyote Creek Watershed

By Maika Nicholson
M.S. Civil and Environmental Engineering, 2012

The San Francisco Estuary Institute’s (SFEI) Historical Ecology (HE) Program seeks to learn how habitats were distributed and ecological functions were maintained within the native California landscape. By understanding how streams, wetlands, and woodlands were organized along physical gradients, a primary aim of the HE Program is to help scientists and managers develop new strategies for more integrated and functional landscape management.

I’m just finishing up my fourth week at SFEI-- another enjoyable day, leafing through the piles of historical maps and texts. Penitencia Creek is located within the Coyote Creek Watershed , on the east side of the Santa Clara Valley near Milpitas. I’m searching for clues about the drainage patterns and habitats that characterized Arroyo la Penitencia, prior to modification in the mid-19th Century. The creek provides significant potential for stream restoration and anadromous fish recover, and the aim of this study is to fill knowledge gaps and inform a number of ongoing and planned environmental restoration and management efforts for the watershed.

Because the creek was modified quite early, historical information from the Spanish and Mexican eras is most useful to understanding this creek’s original form. Searching the historical texts for any mention of little Penitencia Creek has the feeling of looking for needle in a haystack— which makes discovery juicy quotes, such as below, all the more exhilarating.

The rivulet known as the Aguage, but erroneously called by some La Penitencia, and named by the Indians Shistuk, has its origins in the eastern mountains, from which it runs in a westerly course into the valley, and loses itself in the low ground and in the rainy seasons floods the land on which stands the patch of willows near the premises of James Murphy, and whence springs the little stream, the true appellation of which is La Penitencia (Penitence). Its Indian name was Yukisma. This latter stream has a northerly course, passing by and near Milpitas, and discharges itself into the estuary or bay. It received the name of La Penetencia from the fact that the priests from the Missions of Santa Clara and of San Jose used to meet under the shady oaks near its banks, and confess their sins to each other.

-From Frederick Hall 1871, History of San Jose and Surroundings

Some of my favorite maps are the Mexican Land Grant Sketches, called diseños. These colorful maps, while clearly lacking in spatial accuracy, still provide very useful information. The diseños below, for instance, supports the alternate name for upper Penitencia and its original discontinuity from lower Penitencia and Coyote Creeks. It also depicts riparian vegetation, labeled as ‘sausal,’ supporting the presence of willow groves where the creek appears to sink into the coarse soils of its alluvial fan.

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