Water Quality and hypoxia

In a previous post, we celebrated World Water Monitoring Day and highlighted important resources and volunteer opportunities. Today, let’s dive into some of the issues that are monitored to protect the health of our greater Connecticut River and Long Island Sound watersheds.

The Connecticut Department of Energy and Environmental Protection (CT DEEP) is charged with protecting the health of our waters, most notably the Long Island Sound. In the Sound, the state agency conducts water monitoring throughout the year, with a particular focus on hypoxia as it can affect half of the entire Sound every summer. Hypoxia occurs when the water has low or no dissolved oxygen (“DO”) concentrations, and it can be caused or exacerbated by conditions related to nitrogen enrichment and warmer water temperatures. The extra nitrogen can come from “sewage treatment plants, stormwater runoff and atmospheric deposition.” (For more information on stormwater runoff and combined sewage overflows, visit our water facts or Retain the Rain pages.) The excess nitrogen can contribute to the growth of phytoplankton (microscopic plants). When the phytoplankton die, they’re decomposed by bacteria, which use oxygen to break down the plants. These hypoxic areas will have lower oxygen levels and can become “dead zones” that can result in stressed or dead aquatic life. Fish die-offs can also occur in these dead zones.

Extra Nitrogen can encourage plant growth. When those plants die, bacteria will use up oxygen while decomposing the dead plants. Lower oxygen levels can result in stressed or dead aquatic life.

In order to protect the aquatic life and the industries that rely on a healthy ecosystem, it is critical to monitor the water quality of our waters. Monitoring allows us to understand the extent of the issue and track the effectiveness of implemented solutions. CT DEEP and its partners have been monitoring the Sound since 1991, and every year they continue the great work. To see their in-depth reports and annual survey results, you can visit CT DEEP’s website. If you’re interested in national hotspot forecasts on dead zones, algal blooms, and more, you can visit https://oceanservice.noaa.gov/ecoforecasting/ . To help improve water quality in other ways, you can help by reducing stormwater runoff (Retain the Rain), volunteering for water monitoring programs, and participating in cleanups.

Sources: CT DEEP, NOAA

The Retain the Rain program is supported by the National Fish and Wildlife Foundation. The Hartford Mayor’s Office of Sustainability is funded in part by the National Fish and Wildlife Foundation’s Long Island Sound Futures Fund. The views contained in this document are those of the authors and should not be interpreted as representing the opinions or policies of the U.S. Government or the National Fish and Wildlife Foundation and its funding sources. Mention of trade names or commercial products does not constitute their endorsement by the U.S. Government, or the National Fish and Wildlife Foundation or its funding sources.