The US Geological Survey (USGS) maintains data-collection stations throughout Massachusetts. This statewide point datalayer, DCSITE98_PT, represents active and discontinued stations at which USGS collects or had previously collected streamflow data. Though maintained by USGS, the stations are funded by various sources. The points represent four types of data-collection stations. Type 1 stations are streamflow-gaging stations, where data are or have been collected continuously for numerous uses. Type 2 stations are peak-flow partial-record stations, where data are collected only when streamflows are high relative to normal conditions. Data from type 2 stations are used to compute peak-flow frequency statistics, such as the 100-year recurrence interval flood. Type 3 stations are low-flow partial-record or miscellaneous-measurements stations, where data are collected primarily for estimating low-flow statistics, such as the 7-day, 10-year low flow, but data may also be collected at these stations for other purposes specific to individual hydrologic studies. Type 4 stations are those that have been operated both as a type 2 and a type 3 station, either at the same or at different times. Of the 725 stations included in this data layer, data were collected at only 85 streamflow-gaging stations during 1998. All other stations were inactive, but streamflow statistics for all the stations are available.
Data-collection station locations and attributes were derived from the National Water Information System data base of the USGS.
USGS staff created an ascii file of latitude, longitude and attribute data pulled from the data base. This file was then used to generate a point coverage. The coordinates were originally measured from USGS 1:25,000 and 1:24,000 topographic quadrangles with an accuracy to one second.
This data layer has a .PAT with the following items:
|STATION#||data-collection station identifier|
|LONG||longitude of station|
|LAT||latitude of station|
|TYPE||type of data-collection station, where streamflow records are or have been collected:|
|1 = streamflow-gaging station where continuous streamflow records are or have been collected
2 = peak-flow partial-record station
3 = low-flow partial-record or miscellaneous-measurement station
4 = peak- and low-flow partial-record station
MassGIS is maintaining this datalayer. Updates will be made as information is made available from USGS.
|Date published:||November 1, 1998|
|Last updated:||November 1, 1998|