“Bite-Size Bits of Local, National, and Global History”
“Bite-Size Bits of Local, National, and Global History”
San Leandro in Alameda County, California — The American West (Pacific Coastal)

To Build a Dam

To Build a Dam Marker image. Click for full size.
By Barry Swackhamer, February 3, 2014
1. To Build a Dam Marker
Underneath the lake lies evidence of the dams construction. The steps on this panel and the next one show how hands and hooves toiled to complete this engineering feat in 1892.

The rest of this marker consists of three illustration accompanied by captions. They captions are presented here, left to right. Click on the image to enlarge it.

Clearing the area:
Workers “grubbed” (removed) 333 acres of brush and trees from the area to be flooded, to ensure rotting vegetation would not affect the quality of the reservoir’s water.

Tunnel No. 1:
In 1874, laborers dug a spillway tunnel through the rocky hillside to divert San Leandro Creek while constructing the dam. Tunnel No. 1 was originally 30 feet above the canyon floor and later delivered water to homes.

Digging the dam:
To prevent leakage and the creeks’ return, laborers dug three trenches nesting one inside the other. The largest ditch was 900 feet by 150 feet; the second ditch or “puddlepit” was 90 feet from bank to bank and about 140 feet long creek-wise. In the third ditch, laborers constructed three concrete walls and then sealed the trench with concrete grout.

Puddling and compacting:
Laborers spread clay and choice materials obtained
To Build a Dam Marker image. Click for full size.
By Barry Swackhamer, February 3, 2014
2. To Build a Dam Marker
The marker is on the right.
from adjacent areas to fill the two larger trenches. Water from a stream pump kept the clay wet and workable, and would form puddles giving the second ditch, puddle-pit, its name. Laborers drove gangs of horses across the puddle-pit to compact the layers and create a water resistant surface.

”Historians say Chabot was watching some cattle trample across a muddy creek bottom when he got the idea for the primordial impacting plan.”
Oakland Tribune June 9, 1968.

Erected 2012 by East Bay Regional Park District.
Location. 37° 43.804′ N, 122° 7.231′ W. Marker is in San Leandro, California, in Alameda County. Marker can be reached from Estudillo Avenue. Click for map. The one mile Lake Chabot Historical Walk begins at the parking lot at the end of Estudillo Avenue. This marker is about one mile from the beginning of the trail. Marker is at or near this postal address: 1799 Estudillo Avenue, San Leandro CA 94577, United States of America.
Other nearby markers. At least 8 other markers are within walking distance of this marker. Transporting the Water (here, next to this marker); Chabot Dam (a few steps from this marker); Of Fins and Flippers (about 400 feet away, measured in a direct line); Taming the Waters’ Flow (about 700 feet away); Yem-Po: Chinese Labor Camp (approx. 0.2 miles away); Tunnel No. 1 Control Shaft (approx. 0.2 miles away); A Zoo, a Monkey, and a Mansion Here Too! (approx. 0.2 miles away); Filtration Basins (approx. 0.4 miles away). Click for a list of all markers in San Leandro.
Also see . . .  Lake Chabot Historical Walk. (Submitted on February 21, 2014.)
Categories. Man-Made Features
Credits. This page originally submitted on , by Barry Swackhamer of San Jose, California. This page has been viewed 252 times since then and 57 times this year. Photos:   1, 2. submitted on , by Barry Swackhamer of San Jose, California. • Syd Whittle was the editor who published this page. This page was last revised on June 16, 2016.
Paid Advertisement