LOCATION--Lat 42°16'04", long 72°19'59", Hampshire County, Hydrologic Unit 01080204, on left bank at West Ware, 1.4 mi downstream from  Quabbin Reservoir, 3.5 mi east of Belchertown, and 8.0 mi upstream from mouth.
DRAINAGE AREA--189 mi², includes 1.6 mi² drained by Beaver Brook, flow of which is diverted from Ware River basin. Prior to January 1937, 186 mi².
PERIOD OF RECORD--Discharge: July 1910 to September 1912 (twice-daily gage heights and corresponding discharge), October 1912 to current year.
Water-quality records: Water years 1952–54.
REVISED RECORDS--WSP 451: 1916. WSP 871: 1919. WSP 1031: 1944 (changes in reservoir contents and adjusted figures only). WSP 1301: 1925(M). WDR MA-RI-84-1: drainage area.
GAGE--Data Collection Platform with satellite telemeter. Datum of gage is 364.54 ft above NAVD 1988. Prior to May 11, 2020, datum reported as 365.18 ft above NGVD 1929. Prior to Aug. 25, 1912, non-recording gage at site 400 ft upstream at same datum.
REMARKS--Flow regulated since August 1939 by Quabbin Reservoir, usable capacity, 53.8 billion cubic feet. Diversion from Ware River to  Quabbin Reservoir since 1940, from  Quabbin Reservoir to Wachusett Reservoir since 1941, from Quabbin Reservoir to Chicopee Valley aqueduct since 1950, and from Quabbin Reservoir to city of Worcester at times since 1966.

Photo of Swift River looking Downstream

Photo of Swift River looking Upstream