Page Loading - Please Wait...
ICE EFFECTS ON STREAMFLOW
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.
71o09'38", Middlesex County,
Hydrologic Unit 01090001, at building formerly known as Whitefield
Public School in Wilmington, about 30 ft west of State Highway 62 and
0.3 mi north of Concord Street in Wilmington.
AQUIFER--Sand and gravel, glaciated regions; ice contact deposits aquifer.
WELL CHARACTERISTICS--Dug observation water-table well, diameter 42 in., depth 12 ft, cased with stone to 12 ft, open end.
INSTRUMENTATION--Data Collection Platform with satellite telemeter, February 2001 to current year. Digital recorder, October 1984 to January 2001. Continuous graphic recorder, March 1958 to September 1982. Monthly measurement, July 1951 to April 1958, October 1982 to September 1984.
DATUM--Elevation of land-surface datum is 95 ft above National Geodetic Vertical Datum of 1929, from topographic map.
PERIOD OF RECORD--July 1951 to current year. Prior to October 1974, published in Massachusetts Hydrologic-Data Report No. 17.
COOPERATION BY--Massachusetts Department of Conservation and Recreation, Office of Water Resources.