APPENDIX XI.

THE ALBANY WATER-FILTRATION PLANT.

(Abridged from Proceedings American Society of Civil Engineers, Nov. 1899.)

Albany, N. Y., was originally supplied with water by gravity from certain reservoirs on small streams west and north of the city. In time, with increasing consumption, the supply obtained from these sources became inadequate, and an additional supply from the Hudson River was introduced. The water was obtained from the river through a tunnel under the Erie Basin, and a pumping-station was erected in Quackenbush Street to pump it to reservoirs, one of which served also as the distributing point for one of the gravity supplies. The intake, which was used first in 1873, drew water from the river opposite the heart of the city. In recent years, the amount of water drawn from this source has greatly exceeded that obtained from the gravity sources.

The Hudson River, at the point of intake, has a drainage area of 8240 square miles. Of this, 4541 square miles are tributary to the Hudson above Troy, 3493 are tributary to the Mohawk, and 168 are tributary to the Hudson below the Mohawk.

The minimum flow may be estimated at 1657 cubic feet per second, or 1,060,000,000 gallons per 24 hours, or at least fifty times the maximum consumption.

The cities and larger towns upon the river above the intake, with estimated populations and distances, are as follows:

MOST IMPORTANT CITIES, TOWNS, AND VILLAGES ON THE WATERSHED OF THE HUDSON ABOVE ALBANY.
Place. County. Approximate
Distance
above
Intake,
Miles.
Population in
1880. 1890. 1900.
(Estimated.)
Troy Rensselaer     4   56,747   60,956   65,470
Watervliet Albany     4     8,820   12,967   19,040
Green Island Rensselaer     5     4,160     4,463     4,788
Cohoes Albany     8   19,416   22,509   26,450
Lansingburg Rensselaer     8     7,432   10,550   14,980
Waterford Saratoga     9   (1,822)     1,822     (1,822)
Schenectady Schenectady   28   13,655   19,002   26,450
Hoosic Falls Rensselaer   44     4,530     7,014   10,860
Amsterdam Montgomery   44     9,466   17,336   31,730
Glens Falls Warren   49     4,900     9,509   18,450
Saratoga Springs Saratoga   51     8,421   11,975   17,010
Johnstown Fulton   56     5,013     7,768   12,040
Gloversville Fulton   58     7,133   13,864   26,930
North Adams, Mass. Berkshire 68   10,191   16,074   25,340
Adams, Mass. Berkshire   75     5,591     9,213   15,181
Little Falls Herkimer   82     6,910     8,783   11,160
Utica Oneida 107   33,914   44,007   57,090
Rome Oneida 127   12,194   14,991   18,430
32 villages       52,523   61,869   76,194
Total, not including rural population 272,838 354,672 479,415
Per square mile         33         43         59

Without entering into a detailed discussion, it may be said that the amount of sewage, with reference to the size of the river and the volume of flow, is a fraction less than that at Lawrence, Mass., where a filter-plant has also been constructed, but the pollution is much greater than that of most American rivers from which municipal water-supplies are taken.

The filtration-plant completed in 1899 takes the water from a point about two miles above the old intake. Pumps lift the water to the sedimentation-basin, from which it flows to the filters and thence through a conduit to the pumping-station previously used.