From the Austin American-Statesman
http://www.statesman.com/news/conten...riverwalk.html
1870s dam will be part of extended River Walk
Construction crews find forgotten limestone structure while dredging river.
ASSOCIATED PRESS
Saturday, February 09, 2008
SAN ANTONIO — Construction crews dredging a section of the San Antonio River found a forgotten dam built in the 1870s.
The limestone structure was found embedded in the muddy silt that is being removed as part of a project that will extend the River Walk 13 miles, upriver and downriver from the current development.
Project managers hope to incorporate the abandoned dam in the riverfront park that will connect Brackenridge Park north of downtown to the restaurants and retail on the existing River Walk.
"The best we can figure, it's been covered and forgotten for about 100 years," said Mark Sorenson, project manager for the San Antonio River Authority.
"So it is kind of cool uncovering something like this and trying to incorporate it into the project."
The dam was built with cut rocks weighing as much as 1,500 pounds each.
Stretching 120 feet across the old river channel, the dam was altered at some point to allow water to flow over it.
"It is amazing," said Boone Powell, project architect, surveying the dam.
"This is probably the best-built dam the river has ever seen," Powell said.
Project archaeologist Steve Tomka found a 1904 map that shows the dam and a channel that carried the water to the old Alamo Mill for electric power.
The mill processed grain for about 20 years, including in the 1870s.
It's not clear when they were altered to allow water flow, but Fisher said during the 1950s, many flood control projects were used to partially straighten the meandering river channel, and they could have been altered then.
Project officials have not yet decided how the dam will be incorporated in the River Walk extension, but first, it must be fully excavated.
Construction crews will also excavate the bank north of the dam to look for evidence of the old channel that carried water to the mill.