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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.--Middlesex County, Hydrologic Unit 01090001, 10 ft upstream of bridge on River Road, 300 feet downstream of gatehouse outlet from Stony Brook Reservoir, and 2.0 mi southwest of Waltham.
DRAINAGE AREA.--23.7 mi2.
PERIOD OF RECORD.--October 1999 to current year.
GAGE.--Data Collection Platform with telephone telemeter. Datum of streamgage 42.14 ft above NAVD 1988, estimated from topographic map. Previously reported as 43 ft above NGVD 1929, from topographic map. Datum of reservoir gage is 80.30 ft, referenced to the City of Cambridge datum. Subtract 10.84 ft to convert to elevation above NGVD 1929. Subtract 11.70 ft to convert to elevation above NAVD 1988.
REMARKS.--Downstream flow affected by regulation of dam 500 ft upstream at outflow of Cambridge Reservoir.
COOPERATION BY.--Cambridge Water Department

Daily and unit values precipitation data are calibrated and quality assured prior to publication by the Massachusetts-Rhode Island Water Science Center. Data are available upon request.

Available Parameters Available Period
2008-05-23  2016-10-19
2007-10-01  2022-01-16
2010-11-30  2018-04-05
2012-10-01  2017-01-27
2010-09-20  2022-01-16
1999-08-06  2022-01-16
2007-10-01  2022-01-16
2007-10-01  2022-01-16
2008-05-23  2016-10-19
2007-10-01  2022-01-16


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

Elevation of reservoir water surface above datum, feet

Most recent instantaneous value: 74.12 01-16-2022   19:45 EST
Graph of  Elevation of reservoir water surface above datum, feet

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Reservoir storage, million gallons

Most recent instantaneous value: 262.1 01-16-2022   19:45 EST
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