In June 2009, the Connecticut Department of Energy and Environmental Protection (DEEP) proposed a strategy to address the need for a reduction in phosphorus loadings to non-tidal surface waters from municipal wastewater treatment plant discharges.  That strategy has been the topic of numerous discussions between DEEP, stakeholders, and U.S. EPA.  A revised strategy has been developed which is expected to address the concerns raised in the last 18 months by those parties. 

 

 

Phosphorus is a naturally occurring element that is essential to support plant growth. When present in excessive amounts, phosphorus contributes to a process called “eutrophication” that can impair both aquatic life and recreational use of Connecticut’s water resources.  Eutrophication, or nutrient enrichment, is a serious threat to water quality in Connecticut. Excessive loading of phosphorus to surface waters as a result of discharges from industrial and municipal water pollution control facilities (WPCF) or nonpoint sources such as runoff from urban and agricultural lands, can lead to algal blooms, including blooms of noxious blue green algae, reduction in water clarity, and in extreme cases, depletion of oxygen, fish kills, and other impairments to aquatic life. Currently, 21 water body segments have been identified on Connecticut’s List of Waters Not Meeting Water Quality Standards, where nutrient enrichment is a contributing cause of the impairment. Other water bodies that are not currently listed may also be impacted by nutrient enrichment and could cross the threshold to impaired status if nutrient loads from point and nonpoint sources are not effectively managed.

 

Nutrient enrichment has also been identified as one of the most pressing water quality issues facing the nation as a whole. As a result, the Federal Environmental Protection Agency has increased pressure on all states to take aggressive action to limit the quantity of phosphorus being discharged to surface waters. In Region 1, EPA has mandated that all New England states establish limitations on phosphorus in all wastewater discharge permits where the potential exists for the discharge to contribute to eutrophication and impair designated uses in downstream waters.

 

 

The revised strategy addresses concerns regarding the protection of aquatic life in rivers and streams.  The revised strategy uses best available science to identify phosphorus enrichment levels in waste receiving streams that adequately support aquatic life uses.  The methodology focuses on significant changes in stream algae as the key aquatic life response to excess phosphorus loading.  The methods used to develop this strategy were approved by the U.S. EPA in a letter dated October 26, 2010, as an interim strategy to establish water quality based phosphorus limits in non-tidal freshwaters for industrial and municipal WPCF's National Pollutant Discharge Elimination System (NPDES) permits until numeric nutrient criteria are established in Connecticut's Water Quality Standards (WQS).

 

 

The strategy currently only covers waste receiving rivers and streams.  Ongoing work is currently being conducted to refine the approach through additional data collection and by expanding the methodology to include non-waste receiving streams.  It is expected that the ongoing work will lead to numeric nutrient criteria for all freshwater rivers and streams in the next WQS review cycle.

 

 

 

 

Announcement: Open Meetings to Discuss Public Act 12-155, An Act Concerning Phosphorus Reductions in State Waters 

 

PA 12-155 specifically requires DEEP to collaborate with towns on the following:

 

Public meetings were held regarding nonpoint source strategies (11/28/2012), and point source strategies (12/6/2012) for phosphorus controls in CT non-tidal waters. 

 

 

 

 

 

 

DEEP.phosphorus@ct.gov 

 

 

(will be posted and updated here)

 

 

 

Nutrient Enrichment Analysis Watershed Overview  (PDF) Includes proposed phosphorus limits for Publicly Owned Treatment Works