DEEP: Connecticut Healthy Waters Initiative

Healthy Waters in Connecticut
The CT DEEP Monitoring Program has been building multidisciplinary datasets to use with water quality assessments and to reflect our understanding of healthy water in Connecticut. Several efforts are underway and are highlighted below.
{Hubbard Brook}
The Building Blocks of Connecticut's Healthy Watershed Initiative...
Land Cover Studies
CT DEEP has received several US EPA grants to conduct studies on the links between stream health and land cover.  These efforts have led to identification of least disturbed streams (Bellucci et al 2011) and a statewide statistical model of stream health (Bellucci et al 2013).

To learn more about this work:
{A map of Connecticut depicting predicted water quallity conditions.}

Impervious Cover Studies
Impervious surface or impervious land cover (IC) is defined in a variety of ways. A simple definition is any land use alteration which causes water to flow over a surface, instead of soaking into the ground.  Many studies have evaluated the relationship between the water chemistry, fish, and insects living in a stream, and the amount of development upstream.  In general, there is a pattern of natural, very healthy biological integrity under low levels of IC, and degraded poor biological integrity under high levels of IC.
{Graph depicting the relationship between impervious cover and biological integrity}

The Monitoring Program has completed several studies, which tested this conceptual model. The results support the conclusion that even relatively low percentages (12%) of impervious cover upstream of a point on a stream can change stream dynamics enough so that the biological community will no longer meet aquatic life criterion goals.  One bright outcome of this work, however, was the identification of 'Streams of Hope' in Connecticut.  These streams are those that are at a tipping point; active management could potentially return these waterbodies to healthy waters status.

To learn more about this work:
{Map depicting land cover based stream health categories.}
Incorporating the Biological Condition Gradient (BCG) into Assessments 
The Monitoring Program recently developed Biological Condition Gradient models for two of Connecticut's aquatic life communities (fish and macroinvertebrates).  The Biological Condition Gradient (BCG) is a conceptual model that describes changes in aquatic communities. The BCG model provides a more refined way of assigning stream health than a pass/fail approach.  Incorporation of the BCG into Connecticut's water quality assessment process will allow the Monitoring Program to better define and identify healthy waters in Connecticut.
{This graph depicts the relationship between the BCG model and Connecticut}
To learn more about this work:
Increased Biological Monitoring Effort in Least Disturbed Streams 
The miles of monitored healthy rivers and streams has been increasing due to targeting of monitoring on healthy waters from 2012 – 2016.  This is attributed to using our landscape models of stream health to direct our programs monitoring effort as well as the effort of the Volunteer Stream Monitoring Program.
{Graph depicting the number of }
To learn more about this work:
  • The Riffle Bioassessment by Volunteers Story Map. The "Where Should You Monitor Next?" tab combines past Monitoring and Assessment program data with RBV data collected to-date to direct volunteers to those watersheds that have not recently (if ever) been monitored, but that are likely to be characterized by excellent water quality based upon land cover.
  • Integrated Water Quality Report to Congress Prepared Pursuant to Clean Water Act Sections 305(b) and 303(d)
Riffle Bioassessment by Volunteers - A Treasure Hunt for Healthy Streams!
The CT DEEP Riffle Boiassessment by Volunteers (RBV) Program is designed for use on small, wadeable streams that flow year-round and are characterized by fast flowing, rocky habitat called “riffles.”  RBV is a screening approach or a ‘treasure hunt’ for the state’s healthiest streams; if volunteers find four or more pollution sensitive taxa it is evidence of very high water quality.  RBV cannot provide a detailed water quality assessment nor can it be used to identify low or impaired water quality, but it is an excellent screening tool for identifying healthy waters in Connecticut.
To learn more about this work:
{RBV volunteers monitor Railroad Brook in Bolton, Connecticut}
Stream Flow Classification
Water quantity is an important aspect of stream ecology and healthy streams and CT DEEP’s program is one of few in the country to develop regulations and classifications for stream flow. There are 4 stream flow classes that range from Class 1 (near natural) to Class 4 (altered). We have completed stream flow classifications for two-thirds of the state with plans to be finished with the entire state by 2018.
To learn more about this work, please visit
Related Posters and Presentations:
Identification of Cold Water Habitat
The Monitoring Program has developed metrics to describe important water temperature classes in Connecticut streams using paired fish community and water temperature data. Our approach, which is based on a robust set of water temperature and fish community data, should be applicable to other temperate regions and will be useful for informing development of thermal criteria, application of multimetric indices, and planning for anticipated effects of climate change. This work can be used to help identify cold water habitat in Connecticut.
To learn more about this work:
  • Beauchene, M, Becker, M, Bellucci, C, Hagstrom, N, Kanno, Y. 2014. Summer Thermal Thresholds of Fish Community Transitions in Connecticut Streams, North American Journal of Fisheries Management, 34:1, 119-131.  
  • The Interactive Catchment Explorer (ICE) is a dynamic visualization interface for exploring catchment characteristics and environmental model predictions including metrics such as mean summer water temperature, and days above temperature thresholds, in addition to other catchment metrics. The CT DEEP Monitoring and Assessment program contributes stream temperature data annually to the database that feeds the model behind ICE. 
{A wild brook trout. Photo courtesy of Pete Zaidel.}
Further Information
For questions or additional information please contact:
Chris Bellucci
Monitoring Program Supervisor
Bureau of Water Protection and Land Reuse
Connecticut Department of Energy and Environmental Protection
79 Elm Street, Hartford CT 06106
Content last updated April 2017.