XXXIV. OBSERVATIONS ON THE ALG^ OF THE 

 ST. PAUL CITY WATER. 



M. G. FANNING. 



St. Paul receives its water supply from twenty-two lakes 

 north of the city which are situated on both sides of a divide or 

 watershed. The area from which the water is received extends 

 about twenty miles north of the city. The greater part of the 

 water comes immediately from Lake Vadnais, which in return 

 receives its supply from chains of lakes through brooks, artifi- 

 cial canals, conduits, etc. As these lakes are separated by a 

 divide pumping stations are provided at Centreville lake and 

 Baldwin's lake to force the water over the divide. Besides the 

 lakes, groups of artesian wells add to the supply and help to 

 lower the temperature of the water during the summer months. 

 There are nine wells at Lake Vadnais and twenty-eight at Cen- 

 treville lake, making thirty-seven in all with depths varying 

 from sixty-three to eight hundred and sixty-five feet. 



Pleasant lake receives the water from the north slope of the 

 watershed ; from here the water flows from Lake Vadnais, then 

 it is conveyed four and one-half miles through a conduit to the 

 pumping station. The elevated portions of the city receive the 

 water directly from the pumping station. Other parts are sup- 

 plied by gravity with water from Lakes Gervais and Phalen. In 

 order to get sufficient pressure to supply the higher areas, the 

 water is forced into a reservoir one mile west of the pumping 

 station. This reservoir is 290 feet above the water level of the 

 Mississippi river and has a capacity of 18,000,000 gallons. 

 There is another reservoir on the West Side to supply the ele- 

 vated district across the river. 



At the pumping station and also at the entrance of the con- 

 duit leading from Lake Vadnais, a series of graduated wire 

 screens strain from the water the coarser vegetable growth. 



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