Lock and Dam No. 1

Facility

The first facility at the site went into operation in 1917 and superseded the role of the earlier Lock and Dam No. 2 (today known as the Meeker Island Lock and Dam). The facility was rebuilt in 1929, and an expansion from one lock to two locks was completed in 1932. Each lock is 56 ft wide by 400 ft long (17 × 122 meters), half the width of the next lock downstream, though this is the only dual-lock facility in the district. The lift is about 36 ft. Major rehabilitation efforts were carried out between 1978 and 1983, including the replacement of many manual and hydraulic components with computer controls.

The eastern portion of the site consists of an overflow Ambursen dam, which is a buttress dam where the upstream part is a relatively thin flat slab usually made of reinforced concrete. The lift is 36 ft. There is an inflatable flashboard system on top of the dam that can increase the lift by 2 ft when so desired. The lock side of the facility has a large observation area that is open from April to November each year. A bridge allows visitors to walk over the two locks and right up next to the dam.

When the facility opened, it assured a navigable channel up to the tail end of Saint Anthony Falls upriver in Minneapolis. Additional locks were added there in the 1960s, extending the head of navigation to a dam in Coon Rapids (which has no lock), until the closure of the Upper Saint Anthony Falls lock in 2015.

Just upstream of the dam is the Ford Parkway Bridge.

Repair

In November 1958, extensive repairs to the dam began to correct serious leaking from one of the walls, which did not complete until the opening of river traffic in the spring of 1959. To prevent the underwashing of the entire structure, Ashbach Construction filled each wall crack and tunnel by Neoprin and concrete.

Hydroelectric Power Production

The Corps built a base for a hydroelectric plant in the 1917 dam but Federal law required that the plant not be built by the government. Ford built the powerhouse, completed 1924, to power an assembly plant Ford also built on top of the bluff adjacent to the plant. The assembly plant closed in 2011 and the land is being redeveloped for residential and commercial uses. The powerhouse is 156 ft long by 112 ft wide and is built into the east end of the dam. It includes 4 turbines and generators with a total capacity of 17,920 kW using 7,000 cfs of water. It generates about 97,100 megawatt-hours (MWh) a year. Before the closure of the assembly plant, the powerhouse supplied all the electricity to the assembly plant, plus free power to the lock and dam, and 22,000 MWh (22%) was sold to the local power grid. Since the closure of the assembly plant and subsequent purchase of the powerhouse by Brookfield Renewable Power Inc. in 2008 all electricity generated at the facility has been sold on the wholesale market.

Gallery

Ford Dam Powerhouse.jpg|The powerhouse as seen from upstream Lock and Dam number 1 with towboat.jpg|Towboat Patrick Gannaway taking a load of sand and gravel through Lock Number 1. Lock_and_dam_1.jpeg|Lock and dam No. 1 with lock facilities on the left and hydroelectric powerhouse on the right.

References

References

1. [http://www.mvp.usace.army.mil/Missions/Navigation/LocksDams/LockDam1.aspx USACE St. Paul District: Lock and Dam No. 1]
2. "The Secret History of the Mississippi's Earliest Locks and Dams". Minnesota History.
3. Anfinson, John O.. (August 1993). "Mississippi River 9-Foot Channel, Lock & Dam No. 1". Library of Congress.
4. "Oral interview with Jean Ashback-Swanson". Minnesota Historical Society.
5. (November 18, 2004). "Ford Motor Company Twin Cities powerplant license renewal". Federal Energy Regulatory Commission.
6. "Twin Cities Assembly Plant Hydroelectric Dam". City of Saint Paul.