The first step in the development of the WRMP was to take an inventory of independent assessments of watershed resources. Numerous studies of value to the development of the WRMP have also been used to support current USGS, UMass and UConn watershed modeling efforts. All the studies are available in the Coalition's resource library. Selected studies with relevant dates and any associated action items are summarized below.

1. RIVER FLOW DATA - Ongoing
The Pomperaug River gauge at Southbury, operated by the USGS, is collecting real-time data for discharge and gauge height. Seventy-three years of median daily streamflow records are available for this gauge.

Two additional stations, one on the Weekeepeemee and the other on the Nonnewaug River, recorded data intermittently but had been discontinued because of lack of funding. The two stations were reactivated in summer 2000 through the collaborative efforts of the Coalition, the Town of Woodbury, the USGS and Towantic Energy, LLC. (For locations of the gauges, see Figure 4). The data can be accessed from the Coalition's website at: http://www.pomperaug.org/streamflow_data.htm. River gauge funding is assured through 2006; subsequent funding is unclear.

Action Item: The Coalition will work with the USGS to insure continued funding for the gauges.

2. PRECIPITATION/CLIMATE DATA - Ongoing
National Weather Service data is available for the watershed. A new weather station has been purchased as part of the USGS surface and groundwater modeling studies (see Section IV.B.1) and was installed at the Weekeepeemee gauge in Hotchkissville in May 2004. The station monitors wind speed, precipitation, temperature, relative humidity and solar radiation. The gauge is part of the Hydrometeorological Automated Data System, a real-time data acquisition and data distribution system operated by the Office of Hydrologic Development of the National Weather Service. Information from its site can be accessed at http://dipper.nws.noaa.gov/hads/charts/CT.html and through the Coalition's website.

3. REGISTERED/PERMITTED DIVERSIONS - Ongoing
For five years, from July 1997 to July 2002, CT DEP required the reporting of all water diversions over 50,000 gallons per day. Based on that data, and assuming a similar rate of water use for people using the public water supply or private wells, the USGS calculated that the total groundwater use for the basin in one year (2001) was 3.5 million gallons per day.

Future Action Item: The Coalition will work with other river organizations in the state and with the Connecticut Water Planning Council to encourage legislative initiatives that would require the ongoing reporting of all water diversions over 50,000 gallons per day.

4. RESERVOIR DISCHARGE INFORMATION - Ongoing
The Watertown Fire District Water Company routinely releases water from their Lockwood- Bronson Reservoir to supplement flow in East Spring Hill Brook in order to sustain yields in their Nonnewaug well field. The exact quantities of the releases from this and other reservoirs in the watershed are currently unknown. Recording at the USGS gauge on the Nonnewaug River provides a measure of the amount of water released and the duration of releases. This provides the necessary flow data for the USGS modeling efforts (see Section IV.B.4).

Action Item: Discharge records for reservoir releases would be of use to the USGS modeling efforts. USGS has recommended the installation of a staff gauge¹ at the Lockwood-Bronson reservoir. The Coalition will discuss the feasibility of this installation with the Watertown Fire District.

5. SURFACE WATER MONITORING
USGS Precipitation Runoff Modeling System (PRMS) National Research Program - Ongoing

The USGS is using the PRMS to model surface water flows in the Pomperaug. The Pomperaug PRMS model was initially developed as part of a national PRMS evaluation conducted by the USGS National Research Program. Approximately 70 basins across the continental US are part of the study, including the Pomperaug and Salmon Rivers in Connecticut. Information derived from the study has also provided input to the UMass Instream Habitat Program modeling efforts (see Section IV.B.4).

6. GROUNDWATER MONITORING
USGS National Water Quality Assessment and Transport of Anthropogenic & Natural Contaminants - Ongoing

A national USGS water quality study of about 50 watersheds is under way. There are eight study basins in the continental US, including the Pomperaug-the only basin in the Northeast to be included in the study. The purpose of the study is to assess groundwater and contaminant movement in the watershed; delineate source areas for public drinking water supply wells, including septic system return; and provide information on aquifer yield and groundwater baseflow to streams.

As part of the national study, the USGS is using the Modular Finite-Difference Groundwater Flow (MODFLOW) to locate the contributing areas for public water supply wells. This MODFLOW model will be adapted for the more detailed research being conducted by the USGS in Connecticut for the Coalition. For example, the national MODFLOW model area includes the entire Pomperaug watershed upstream from the Southbury gauge excluding the Sprain Brook sub-watershed.

For more information on these studies, visit: http://water.usgs.gov/nawqa/ and http://webserver.cr.usgs.gov/nawqa/hpgw/activities/TANC.html.

7. WATER QUALITY MONITORING - Ongoing
A variety of water quality data for the Pomperaug watershed has been collected regularly for many years by the Woodbury Conservation Commission, the CT DEP and the USGS. The Coalition has gathered much of this data as either electronic or printed reports for its modeling efforts and makes the reports available through its resource library.

The Coalition's Water Quality Committee, a sub-committee of the Board, is considering instituting a basic, ongoing surface and ground water monitoring program that crosses town boundaries and provides a consistent, ongoing measure of the environmental health of the Pomperaug (see Section IV.C.4).

Additional water quality studies in the watershed include:

UConn Prescription Drug Study: Analysis of drug metabolites in surface waters downstream of Heritage Village wastewater treatment plant discharges. For an article discussing this issue see the Fall 2006 issue of Natural Resources Defense Council's magazine, OnEarth, click here.

CT DEP Studies: These include oversight of various ground water contaminant plumes resulting from leaking underground storage tanks. These releases are located in sand and gravel deposits and pose both short and long term threats to public water supply wells.

Action Item: The Coalition's Water Quality Committee is currently inactive. The Coalition board, however, is following the progress of these studies and will evaluate the significance of results as they become available.

8. GEOLOGIC INFORMATION
The USGS National Bedrock Regional Aquifer Systematic Study (BRASS): Geologic Mapping in the Pomperaug Basin - November 2003 through 2006.

The purpose of this national study is to achieve an in-depth understanding of the relationship between bedrock well-water yield and rock type. The geology of the Pomperaug basin is currently mapped on parts of four USGS maps that were developed at different times. As a part of the national BRASS, the Pomperaug watershed is the focus of a single new map unit. A new 1:24,000-scale geologic map is planned for the Pomperaug basin. This basin comprises part of the Pomperaug River watershed, an area with significant ground-water supply issues, and it was identified as the area in greatest need of new geologic mapping by the State Geologist of Connecticut. For more information on the study, visit: http://geology.er.usgs.gov/eespteam/brass/states/ct/ct2.htm.

The information obtained from BRASS may be useful in helping to evaluate the accuracy of the USGS Connecticut MODFLOW model results, especially in areas that may be influenced by groundwater flow in fractured or faulted bedrock.

9. SOURCE AREA MAPPING FOR PUBLIC WATER SUPPLY WELL
Detailed final aquifer protection area Level A mapping of the area of ground water that contributes to each public water supply well is required of water companies within the watershed under Connecticut's new Aquifer Protection Area Program by 2007 (CT General Statutes Sections 22a-354a et sec). The purpose of the program is to identify critical water supply aquifer areas and protect them from contamination by managing land uses in these areas.

Information from Level A mapping will be useful in verifying the Coalition's watershed modeling results. Similarly, recharge information from watershed modeling efforts can save water companies significant time and money on Level A mapping efforts. Currently the only the Southbury Training School Level A mapping has be completed. Water companies have been sending representatives to the Coalition's meeting to learn how and if the USGS modeling can be of use in their Level A mapping efforts.

10. IMPERVIOUS SURFACE BUILD-OUT (ISB) ANALYSIS
An ISB analysis of the impact of population growth on water quality in the watershed was completed in 2003 by the Council of Governments of the Central Naugatuck Valley (COGCNV) in conjunction with the UConn Cooperative Extension System's Nonpoint Education for Municipal Officials Project. The results were submitted to the USGS for use in the watershed model. COGCNV and the Coalition have presented these maps to all watershed towns and have suggested regulatory updates.

11. LAND USE INFORMATION
Land use patterns in the watershed were mapped using GIS technology by COGCNV in 2003 and were submitted to the USGS for developing their watershed model. These computer-generated maps will be easy to update and link to other layers of digital information and should prove useful to municipal officials and town planners.

12. SECURITY ISSUES
COGCNV is working on a Disaster Mitigation Plan to identify possible public water security issues. The proposed target date for completion is 2006.

Action items: The Coalition will follow the progress of the plan and assist as necessary. Results will be incorporated into WMP updates as appropriate.