Santa Clara Slough

Santa Clara Slough is an old delta arm of the Colorado River. Old maps show the Slough extending from this location north thru the Cienega de Santa Clara, & connecting with the main channel of the Colorado just west of Ciudad Coahuila.
Map is here, at pg 1219:
books.google.com/books?id=MIRBAQAAIAAJ&lpg=PA1553&ots=S...
The Santa Clara Slough is also called the Santa Clara River in old navigation records.

Desc of the slough/river from the late 1800s:
"Santa Clara River, about 10 miles from the low point fronting Direction Sandhill, is only navigable at high water; at low-water springs [referring to a spring tide] it is dry, with the exception of here and there a pool of water.
The sand hills and table-lands, which up to this point have run parallel with the coast, here assume a more northerly direction, following the course of the Santa Clara river.
Santa Clara beacon is on the west side of the mouth of the river, and consists of a couple of piles with a piece of board nailed across the top."
books.google.com/books?id=OwUOAQAAIAAJ&printsec=frontco...
From: The West Coasts of Mexico and Central America. Chiefly from surveys by the United States Steamers Narragansett, Tuscarora, Ranger, and Thetis, between 1873 and 1901. at pg 155-156

1873 map of the delta is here:
fire.biol.wwu.edu/trent/alles/GeologySaltonTrough.pdf
at pg 20