Alum Creek Lake

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Template:Use American English Script error: No such module "Infobox".Template:Template otherScript error: No such module "Infobox body of water tracking".Script error: No such module "Check for unknown parameters".

File:Alum Creek Dam 3.JPG
When the dam was constructed in 1974 it was out in the country. Today, modern homes reach nearly to the base of the dam. View from the top of the dam looking south.

Alum Creek Lake is a man-made reservoir located in Delaware County, Ohio, United States. It was built in 1974, covers Script error: No such module "convert"., and has a maximum capacity of Script error: No such module "convert"..

Dam construction (1970–1974)

Alum Creek Dam was constructed between 1970 and 1974 on Alum Creek, a tributary of Big Walnut Creek, which drains into the Scioto River. The dam is a rolled earth-fill embankment Script error: No such module "convert". in length with a maximum height of Script error: No such module "convert".. The spillway is located high on the right abutment with the raceway dropping off in front of it to the stilling basin below. Control is provided by three Script error: No such module "convert". by Script error: No such module "convert". tainter gates supported by Script error: No such module "convert". wide concrete piers resting on concrete ogee sections. The ogee sections have a crest elevation of Script error: No such module "convert". and are founded at Script error: No such module "convert". elevation.

File:Alum Creek Dam.JPG
Alum Creek Dam spillway. Water is normally discharged through the hole in the far wall. Three large gates can be opened to provide emergency control under high water conditions. The retrofit cables were installed in the large flat calming section at the base of the dam.
File:Alum Creek Dam 2.JPG
The Alum Creek Dam spillway is perched high on the abutment; this prompted concerns within the Army Corps of Engineers about deep-seated sliding.

Potential dam failure and retrofit (1975–1978)

On April 24, 1975, during a periodic inspection of the completed dam, the US Army Corps of Engineers expressed concern about the safety of the spillway monoliths. The rock underlying the dam is Ohio Black Shale which is a largely hard, massive silt shale. It is highly fractured below the base of weathering. Within this shale are several light gray, silty to clayey shale seams up to Script error: No such module "convert". thick. It may be possible that the spillway monolith and its underlying bedrock could slide forward on one of these seams, opening a gap between the monolith and the rolled earth dam leading to rapid and catastrophic erosion of the dam.

Testing

Twelve, Script error: No such module "convert". diameter core holes were drilled in the raceway directly in front of the ogee weirs. At least six of these cores exhibited a clayey seam about elevation 830 (nine feet below the ogee foundations). Testing of this material and deep-seated sliding analysis indicated that the dam did indeed face a safety issue.Script error: No such module "Unsubst".

Retrofitting

To prevent the concrete monolith from sliding forward, it was decided to install seven cable anchors deep into the bedrock. Each anchor consisted of bundled, high strength steel cables that were concreted into the bottom of the holes. They were then hydraulically tensioned and the holes filled with grout. Anchors were installed at a 45-degree angle to a depth of 813, or Script error: No such module "convert". below the foundation of the ogees. On March 2, 1977, the project was bid to VSL Corporation for $254,777. Drilling for the anchors began on June 7, 1977. The final loading on each anchor was 1300 kips. On September 28, 1977, one of the anchor's foundations failed and had to be re-concreted. By 1978, the project was completed.Script error: No such module "Unsubst".

January 2005 flood

Script error: No such module "Unsubst". On January 16, 2005 Alum Creek Dam's reservoir reached its highest level since construction was completed in 1974, an elevation of 898.94, about Script error: No such module "convert". above normal level. At this level control was maintained through the discharge pipe and it was not necessary to open the three main spillway gates.

This extreme event was caused by an average of Script error: No such module "convert". of rain falling over Central Indiana and Ohio during January 4–14, 2005. This rain combined with snow melt and saturated ground to produce record breaking runoff. Other reservoirs also set pool level records, including Deer Creek, Delaware Lake, Paint Creek, Atwood Lake, Bolivar Dam, Charles Mill Lake, Dillon Lake, Dover Dam, Mohawk Dam and Wills Creek.

Recreation

Alum Creek Lake is popular with locals and regional tourists alike with its fishing, picnicking, boating, disc golf course, kitesurfing and hiking opportunities.

References

<templatestyles src="Reflist/styles.css" />

Script error: No such module "Check for unknown parameters".

External links

Template:Authority control