Two Zone Pressure System Instituted at Schenectady
To place in operation a two-zone pressure system in Schenectady, N. Y., the four pumps at the Rotterdam pumping station were shut down for a 36-hour period during which the city was supplied by the Bevis Hill reservoir. The two-zone system is for the purpose of equalizing the pressures in the higher and lower districts of the city. A chain of reducing valves were installed at different points of mean elevation to regulate the pressure. Superintendent of Water Townsend explains that should the water be permitted to flow direct to the downtown districts without check, the extreme low sections would have a pressure of approximately 120 pounds, there being a difference in elevation, with the reservoir full, of 290 feet. Such pressure would be too great for general purposes and more than the mains would carry with safety. The regulating valves were installed to correct this condition. These valves so divide the pressure that at the “upside” of the valves it will be practically the same as in the lower section of the city, while the pressure in the higher sections above the valves will correspond to the same comparative heads in the lower districts. These valves feed from the upper to the lower zone and operate with varying pressures so that if the pressure in the lower zone tends to drop below normal the valves will be immediately open to supply the deficiency. In case of a big fire in the downtown district and the sudden failure of pressure there, these valves would open automatically, allowing the supply from the reservoir to flow into the downtown section. Or if the pumps supplying downtown should get out of order the pumps supplying the upper zone would come to the rescue of the lower district through these valves. The city now has three pumps which supply the upper and lower zones and one pump connected with the upper zone and reservoir and another pump which will be connected with the lower zone after its motor has been overhauled by the General Electric Company.
The Springfield, Ill., water department upon the advice of the State Water Survey department, is now ready to install a chlorinating apparatus for the purpose of protecting its water supply should necessity arise. At all ordinary times, the city water has been found by repeated tests to be pure and healthful, but whenever it falls below the recognized standards of purity, it will be sterilized by chlorine gas, the apparatus for generating which the city council will purchase at a cost of about $1,500.