WATER FOR WISCONSIN CITIES.
William S. Kirchoffer, of the University of Wisconsin, has published an interesting paper describing in detail the sources of water supply of 120 of the cities and towns of Wisconsin. He is thoroughly competent to treat of the subject, as he has had charge of the installation of water works thirty-eight times in several cities of the State, to which he has been called as consulting engineer. Of the 270 towns and villages in the State 120 have been provided with public water supplies. Of this number fifty arc supplied with artesian well water; thirty, from ground water from shallow, open or driven wells and springs; fourteen, with lake water; and twelve with river water. Of the cities using river water, only six use it for general supply, the others using it for fire protection and mechanical purposes. The ground water supply seems to be the least satisfactory as to both amount and quality of water, although some of them are not as poor as the worst of the river and lake water. I11 regard to the amount of water used from various sources: Lake waters rank first; artesian well water, sec ond; ground waters, third; and river water, fourth. As to the sufficiency of quantity: Lake waters rank first; river waters, second; artesian waters, third; and ground waters, fourth. Wisconsin cities which use river water for domestic supply are comparatively few. The principal use of river water for domestic purposes is by large interior cities, many of which are on the Wisconsin river. All of the sources used for domestic purposes are contaminated to some extent with sewage, and the streams flowing from the forest area are colored, more or less, by pine and hem lock. All the streams carry large quantities of sediment in the spring anil require purification. Of the 2.500 lakes in the State only six are used for public supplies. As is quite natural, lake Michigan and lake Suoerior supply more cities and a greater number of people than all the others combined. Only four cities getting their water from lakes filter it before use. The others draw the water directly from the lake without treatment. In lake Michigan the conditions for a pure supply are much better than in lake Superior, so far as Wisconsin is concerned, because of the position of the bavs of lake Superior and the drainage into them. The waters of the great lakes, of course, are pure at a considerable distance from the shore, and it is only the local contamination along the shore that makes it necessary to purify them.
