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WQP Home >  Providers >  STORET >  UMMP >  UMMP-UMMP-11

#11 MERRIMACK RIVER GARVINS FALLS (UMMP-UMMP-11) site data in the Water Quality Portal

Data Provider: STORET (Learn more about Water Quality Portal Data Providers)

This river/stream site, maintained by the UPPER MERRIMACK RIVER LOCAL ADVISORY COMMITTEE (Volunteer) (identifier UMMP), has the name "#11 MERRIMACK RIVER GARVINS FALLS" and has the identifier UMMP-UMMP-11. This site is in the watershed defined by the 8 digit Hydrologic Unit Code (HUC)01070006.

This site is located in Merrimack County County, New Hampshire at 43.1647220000 degrees latitude and -71.5075000000 degrees longitude using the datum NAD83. The horizontal location collection method was "GPS-Unspecified" and the accuracy is 15 m.

To download the metadata about this site along with water quality data, go to the Portal Page and enter "UMMP-UMMP-11" into the "Site ID" box under Site Parameters

What other monitoring locations are upstream or downstream from this one?

Upstream and downstream locations

This map shows all Water Quality Portal stations that are 10 miles upstream (dashed dark blue) and 10 miles downstream (solid light blue) of this monitoring location (indicated by the large blue circle). The upstream and downstream functionality is provided by the Network Linked Data Index.

Leaflet USGS The National Map: National Boundaries Dataset, 3DEP Elevation Program, Geographic Names Information System, National Hydrography Dataset, National Land Cover Database, National Structures Dataset, and National Transportation Dataset; USGS Global Ecosystems; U.S. Census Bureau TIGER/Line data; USFS Road data; Natural Earth Data; U.S. Department of State HIU; NOAA National Centers for Environmental Information. Data refreshed February, 2025.

When were data collected at this location?

Periods of record for data characteristic groups

For a more detailed breakdown of data, go to the Monitoring Report at the EPA How's My Waterway Application
Characteristic Group Date Range*
Microbiological 1996 - 2019
*Date ranges may contain gap years

What other information is available for this location?

Detailed Metadata

For the definitions of the metadata elements, please go to the Water Quality Portal user guide

Location Metadata Value
OrganizationIdentifier UMMP
OrganizationFormalName UPPER MERRIMACK RIVER LOCAL ADVISORY COMMITTEE (Volunteer)
MonitoringLocationIdentifier UMMP-UMMP-11
MonitoringLocationName #11 MERRIMACK RIVER GARVINS FALLS
MonitoringLocationTypeName River/Stream
MonitoringLocationDescriptionText UMMP SITE #11 IS SITUATED IN THE BYPASS REACH OF THE PSNH OWNED AND OPERATED GARVINS FALLS DAM. THE BYPASS REACH IS CHARACTERIZED BY SWIFT FLOWS, COBBLE, BOULDERS, AND COARSE GRAVELW WHILE THE MAINSTEM IS DOMINATED BY FINES. THE ACTIVE SPILLWAY OF THE DAM IS WITHIN 100' OF THIS LOCATION. BACTERIA SAMPLES ARE COLLECTED FROM THE PORTAGE BOAT ACCESS AND ROCK BASKETS ARE DEPLOYED IN THE BYPASS REACH. THERE IS AMPLE RIPARIAN BUFFER ALONG RIVER LEFT BUT LARGE GAPS IN THE BUFFER ALONG RIVER RIGHT. THERE IS A LARGE ISLAND VISIBLE IN THE MERRIMACK RIVER DOWNSTREAM OF THIS LOCATION.
HUCEightDigitCode 01070006
LatitudeMeasure 43.1647220000
LongitudeMeasure -71.5075000000
HorizontalAccuracyMeasure/MeasureValue 15
HorizontalAccuracyMeasure/MeasureUnitCode m
HorizontalCollectionMethodName GPS-Unspecified
HorizontalCoordinateReferenceSystemDatumName NAD83
CountryCode US
StateCode 33
CountyCode 013
ProviderName STORET