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The formation of ice on rivers can cause discharge values to appear unusually high. Display of these erroneous discharge data may result in improper assessment of flow conditions and misuse of the data. For this reason, display of discharge values for streams significantly affected by ice may be disabled from view. Display of discharge data will resume when ice conditions are no longer present. Discharge values for streams minimally affected by ice will continue to be displayed. Flows for streams with these conditions appear to increase during the night and decrease to near-base-line conditions around midday. To estimate the correct discharge for these streams, use the flow rate that corresponds to the bottom of the discharge curve, rather than the peak that corresponds to the top of the curve. Note that this method of estimation is possible only when no surface runoff is occurring. Daily mean discharges for periods of both significant and minimal ice-effect will be estimated and published in the Annual Water-Data Report for the water year in which they occurred.

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LOCATION--Lat 42° 22’20", long 71° 14’03", Middlesex County, Hydrologic Unit 01090001, on right bank 800 ft downstream from Moody Street Bridge in Waltham and 0.3 mi upstream from Beaver Brook.
DRAINAGE AREA--227 mi2, excludes 23.6 mi2 drained by Stony Brook, from which flow is diverted for municipal supply of Cambridge.
PERIOD OF RECORD--Discharge: October 1903 to October 1909 (figures of average weekly discharge, equivalent to records of unadjusted discharge at present site), August 1931 to current year.
Water-quality records: Water years 1953, 1959, 1968–70.
REVISED RECORDS--WSP 781: 1933(M). WSP 851: drainage area. WSP 971: 1942.
GAGE--Data Collection Platform with satellite telemeter. Datum of gage is 19.21 ft above NAVD 1988. Datum previously reported as 20.02 ft above NGVD 1929. Prior to July 10, 1904, at dam 700 ft upstream and July 10, 1904, to Oct. 2, 1909, at dam 0.7 mi downstream at different datums; discharge computed from flow over dam and through wheels and gates of Boston Manufacturing Co. and Waltham Bleachery, respectively.
REMARKS-- Flow affected by diversion to Mother Brook (station 01104000), diversions to and from basin for municipal supplies, and at times by water released from Stony Brook Reservoir. Prior to 1960, some regulation by mills upstream. Low flow completely regulated by Boston Edison Co. power plant prior to 1954.
COOPERATION BY--Massachusetts Department of Conservation and Recreation, Division of Planning and Engineering.

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This station managed by the Northborough MA Field Office.

Available Parameters Available Period
1976-02-01  2022-01-20
2007-10-01  2022-01-20


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Summary of all available data for this site
Instantaneous-data availability statement

Discharge, cubic feet per second

Most recent instantaneous value: 495 01-20-2022   06:30 EST
Graph of  Discharge, cubic feet per second

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Daily discharge, cubic feet per second -- statistics for Jan 20 based on 90 water years of record more
Median Mean 75th
Most Recent
Value Jan 20
53.0 226 301 360 480 495 1020

Gage height, feet

Most recent instantaneous value: 2.38 01-20-2022   06:30 EST
Graph of  Gage height, feet

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