The Ludington Pumped Storage Power Plant was built on a sandy, dune-like bluff, high above Lake Michigan near Ludington, Mich. It was built for Consumers Power and Detroit Edison by Ebasco Services of New York, N.Y. The mass excavation was handled by Walsh-Canonie Companies, a joint venture of Walsh Construction Company of Valparaiso, Ind., and Canonie Construction Company of South Haven, Mich. Construction began in 1969 and was completed in 1973 at a cost of $327 million.
The hydro-electric plant uses six reversible pump-turbines that, at peak, can produce 1,872 megawatts. The 842 acre manmade reservoir is 2 mi. (3.2 km) long by 1 mi. (1.6 km) wide, created by the excavation of the reservoir, and a 6 mi. (9.7 km) long continuous dike. The average height of the dike is 100 ft. (30.4 m) and its crest is 21 ft. (6.4 m) wide. The reservoir holds 27 billion gallons of water. The power plant has been likened to a storage battery in so far as it can be placed on line at full capacity within minutes. At night, during off-peak hours, the turbines are reversed to pump water from Lake Michigan into the upper reservoir.
The poor sandy soils available for construction made for careful compaction and required the reservoir bottom be sealed with a 5 to 8 ft. (1.5 to 2.4 m) layer of impervious clay. The waterside of the dike was paved with sandwich layers of asphaltic material and two surface courses of 2½ in. (6.4 cm) thick hydraulic asphalt concrete. The HAC contains a high proportion of mineral filler to make it virtually impervious. The material had been used extensively in Germany.
The first stage of excavation totaled five million cubic yards. The work began on July 14, 1969 and involved excavating a trench from the bottom of the storage reservoir to Lake Michigan for the power plant penstocks, the power house site, and a number of road relocations. Initially, 43 Terex TS-24 twin-engined scrapers were used along with five smaller Terex TS-14 twin-engined scrapers. A Barber-Greene belt loader charged with several large bulldozers also was in use at this point. The belt loader was top loading some of the scrapers. It was used largely to prevent pollution of Lake Michigan. Draglines also were used at the edge of the 344 ft. (104.9 m) high bluffs to keep the scrapers from operating that close to the cliffs overlooking Lake Michigan. At the end of August, 50,000 cu. yds. (38,228 cu m) of dirt was being moved daily. Early October a second shift was added.
The second stage of excavation began in early 1970 and totaled 33 million cu. yds. (25 million cu m) to construct the reservoir and dikes. The all-Terex scraper fleet eventually grew to 95 units as the excavation ramped up. The scrapers included a total of 81 TS-24s, nine S-24s (single-engine), and five TS-14s. The spread achieved a single day record of 180,000 cu. yds. (137,620 cu m).
A $20 million dollar joint-venture subcontract for the dike embankment paving was awarded to Morrison-Knudsen and Strabag Bau A.G. of Cologne, Germany. The contractors used four giant bridge-type paving machines built by Rex-Arbau in Germany. The pavers spanned 149 ft. (45.4 m) and were the largest ever built. The pavement totaled 840,000 sq. yds. (702,347 cu m). -CEG