"On This Day" In Engineering History

On this day in engineering history, the New York City Board of Water Supply ordered the burning of buildings in the town of Gilboa. This final fire destroyed the remaining structures on the old Richmyer Farm, dropping parts of the upstate landscape below the water line for a new reservoir.

In 1918, New York City had purchased the rights to Gilboa and the surrounding Schoharie Valley when the area around Prattsville proved impracticable for a water supply. During the next seven years, 25 homes, 12 barns, a church, and a garage were burned; 1,330 graves were moved; and 200 residents of Gilboa were relocated. The result, a reservoir, is now part of a water supply that some term "one of the engineering marvels of the modern world".

The Schoharie Reservoir

Designed to water The Big Apple, the Schoharie Reservoir is fed by the Schoharie Creek, a tributary of the Mohawk River. In 1923, work began on the Gilboa Dam, a 120-foot tall structure that holds back the river's waters. Made of concrete and reinforced with stone bricks, the Gilboa Dam was completed in 1926 and put into service that same year. The resulting reservoir consists of a single 6-mile basin that holds 17.6 billion gallons of water at full capacity. Although the Schoharie Reservoir is one of the smallest of New York City's 19 reservoirs, it now provides 9 million people with 15% of their annual water supply needs.

The Path Downstream

Water from the Schoharie Reservoir flows south to New York City via the Shandaken Tunnel, an 18-mile long aqueduct that slopes at rate of 4.4 feet per mile. Measuring 11.5 ft. high and 10.2 ft. wide, this tunnel features seven shafts that serve as air vents, introducing oxygen into the water. After flowing into a manmade lake at Allaben, waters from the Schoharie Reservoir empty into Espous Creek. From there, the water supply travels 11 miles to the Ashokan, New York City's deepest reservoir. After leaving the Ashokan Reservoir, the waters enter the 92-mile Catskill Aqueduct and then travel to the Kensico Reservoir. From there, water flows into New York City.

Resources:

http://www.catskillcenter.org/programs/edu/csp/H20/Lesson4/lesson4.htm

http://en.wikipedia.org/wiki/Schoharie_Reservoir

http://en.wikipedia.org/wiki/Shandaken_Tunnel

http://en.wikipedia.org/wiki/Gilboa,_New_York