THE LOWELL, MASS., WATER WORKS.
LOWELL, Mass., is noted for its driven wells system and its filtration methods. Its series of driven wells has recently been increased and connected. The latest addition is that formed — by the connection of the “ Andrews wells”at the Poor farm with the Cook plant, being a gang of seven wells put down in 1892, also twelve additional wells. The Cook plant was lowered eight feet at the same time. The amount of water was thereby increased as well as the efficiency of the plant, which has averaged 2,457,002 gallonsdaily. Our illustrations show the force-main pipes temporarily and permanently connected,also a novel first-class machine built at the department shops for the purpose of driving wells.
I’he seven Andrews wells were connected with the pump by 953 feet of 10-inch cast iron pipe, with llange joints, the eleven next driven wells along the pipe have been connected with it, and form the first tube-well plant. The second contained in the beginning forty two 2-inch wells, 45 feet deep, placed on east side of a 12-inch suctionmain, 25 feet apart,and 6 feet from the suction main, all the connec tions being at an angle of forty-five degrees with the main These, on being tested by metcr-me.suremer.t for 16 days, 11 hours, 23 minutes, pumped 29,972,597 gallons^—the ground during the test being lowered about 10 1-2 feet.
Another section of seventeen wells was then built, and tested by pumping 6 days. 15 hours, 34 minutes (during which time the suctionmain, which was near the surface, was loweretl about 5 feet), yielding 5,283,599 gallons. By this lowering the ground-water (by lowering the wells already driven) the difficulty of lowering the main, building the foundation for the permanent pumps, and excavating for the pit, was overcome. Those permanent pumps were then utilized and the wells of the second section pumped, while the suctionmain of the first was in its turn lowered. All this time 2,300,000 gal Ions of water were being daily pumped into the city mains. The construction of the third section was then begun. It was laid out at right-angles to the two and finished in four months (part of the line being in use long before). Here was found a very deep deposit of soil, 300 feet in length, and varying from 6 to 35 feet in depth. No wells were driven here, and piles supported the suction-mains, four being driven through to the underlying gravel for every 12-foot length of pipe. The plant now consists of 120 wells connected by 1,519 feet of 12-inch suctionpipe; two Worthington engines, each capable of pumping 3,000,000 gallons per day, doing the pumping. From April 5, 1895, to January 1, 1896, 814,076,753 gallons of water (a daily average of 3,015,099 gallons) were pumped and mens ured by a Venturi measure. The third tube-well plant, on the Pawtucket boulevard, had its first line of wells laid 34 feet south of, and parallel to the south line of the boulevard. Sixty wells were driven on this line, yielding, however, so little water that the line was not extended. Twenty-six of these wells were connected temporarily and pumped four days, yielding 570 gallons per minute, the ground being meanwhile lowered 12 feet. A line of sixty wells was then driven parallel to the first,and 2,010 feet nearer the river. These were connected and tested in groups of twenty each, the average yield per well being thus 25 gallons per minute. There being too much free ammonia in these wells, operations ceased, and a line of twenty-two wells was then driven at right angles to, and connecting with the above section. Except live, all these proved good. A line of of 122 wells was then driwn and tested in groups of from fifteen to twenty each, all yielding excellent water. They are of 21-2 inches in diameter and vary in depth from 25 to 40 feet. The water-bearing stratum lies about t.venty five feet below the surface at a depth varying from 5 to 15 feet. The earth above this stratum is composed of very fine sand and river silt, which is almost impervious to water.
All the water sold by the city is now metered,the free meter system being adopted. To pay for the meters in use previous to this system being adopted a loan of $40,000 was authorized, it being the plan to refund to meter-owners the amount paid, less to pet cent, per year, while in use—any meter that had been in use ten years being considered as having served its usefulness, although it might last a great while longer; but it would have to Ire replaced by the city. This entailed the purchase of about 2,000 meters.
Waycross, Ga., expects to net $2,4 this year from water rents, tapping, and plumbing. The total expenditure, it is thought, will amount to $2,755. Tile water works will soon be on a paying basis.