objective

Pathogens

Reduce pathogens and increase monitoring to protect water quality and human health, ensuring safe recreational and commercial use.

Year	Percent of beaches graded B- and above	5 year rolling average	2035 Goal
2003	66%	n/a	85%
Year 2003 Percent of beaches graded B- and above 66% 5 year rolling average n/a 2035 Goal 85%
2004	69%	n/a	85%
Year 2004 Percent of beaches graded B- and above 69% 5 year rolling average n/a 2035 Goal 85%
2005	80%	n/a	85%
Year 2005 Percent of beaches graded B- and above 80% 5 year rolling average n/a 2035 Goal 85%
2006	73%	n/a	85%
Year 2006 Percent of beaches graded B- and above 73% 5 year rolling average n/a 2035 Goal 85%
2007	71%	72%	85%
Year 2007 Percent of beaches graded B- and above 71% 5 year rolling average 72% 2035 Goal 85%
2008	88%	76%	85%
Year 2008 Percent of beaches graded B- and above 88% 5 year rolling average 76% 2035 Goal 85%
2009	80%	78%	85%
Year 2009 Percent of beaches graded B- and above 80% 5 year rolling average 78% 2035 Goal 85%
2010	65%	75%	85%
Year 2010 Percent of beaches graded B- and above 65% 5 year rolling average 75% 2035 Goal 85%
2011	66%	74%	85%
Year 2011 Percent of beaches graded B- and above 66% 5 year rolling average 74% 2035 Goal 85%
2012	70%	74%	85%
Year 2012 Percent of beaches graded B- and above 70% 5 year rolling average 74% 2035 Goal 85%
2013	82%	72%	85%
Year 2013 Percent of beaches graded B- and above 82% 5 year rolling average 72% 2035 Goal 85%
2014	79%	72%	85%
Year 2014 Percent of beaches graded B- and above 79% 5 year rolling average 72% 2035 Goal 85%
2015	83%	76%	85%
Year 2015 Percent of beaches graded B- and above 83% 5 year rolling average 76% 2035 Goal 85%
2016	75%	78%	85%
Year 2016 Percent of beaches graded B- and above 75% 5 year rolling average 78% 2035 Goal 85%
2017	79%	79%	85%
Year 2017 Percent of beaches graded B- and above 79% 5 year rolling average 79% 2035 Goal 85%
2018	73%	78%	85%
Year 2018 Percent of beaches graded B- and above 73% 5 year rolling average 78% 2035 Goal 85%
2019	70%	76%	85%
Year 2019 Percent of beaches graded B- and above 70% 5 year rolling average 76% 2035 Goal 85%
2020	84%	76%	85%
Year 2020 Percent of beaches graded B- and above 84% 5 year rolling average 76% 2035 Goal 85%
2021	83%	78%	85%
Year 2021 Percent of beaches graded B- and above 83% 5 year rolling average 78% 2035 Goal 85%
2022	78%	78%	85%
Year 2022 Percent of beaches graded B- and above 78% 5 year rolling average 78% 2035 Goal 85%
2023	73%	78%	85%
Year 2023 Percent of beaches graded B- and above 73% 5 year rolling average 78% 2035 Goal 85%
2024	72%	78%	85%
Year 2024 Percent of beaches graded B- and above 72% 5 year rolling average 78% 2035 Goal 85%
2025	77%	77%	85%
Year 2025 Percent of beaches graded B- and above 77% 5 year rolling average 77% 2035 Goal 85%
2026	n/a	n/a	85%
Year 2026 Percent of beaches graded B- and above n/a 5 year rolling average n/a 2035 Goal 85%
2027	n/a	n/a	85%
Year 2027 Percent of beaches graded B- and above n/a 5 year rolling average n/a 2035 Goal 85%
2028	n/a	n/a	85%
Year 2028 Percent of beaches graded B- and above n/a 5 year rolling average n/a 2035 Goal 85%
2029	n/a	n/a	85%
Year 2029 Percent of beaches graded B- and above n/a 5 year rolling average n/a 2035 Goal 85%
2030	n/a	n/a	85%
Year 2030 Percent of beaches graded B- and above n/a 5 year rolling average n/a 2035 Goal 85%
2031	n/a	n/a	85%
Year 2031 Percent of beaches graded B- and above n/a 5 year rolling average n/a 2035 Goal 85%
2032	n/a	n/a	85%
Year 2032 Percent of beaches graded B- and above n/a 5 year rolling average n/a 2035 Goal 85%
2033	n/a	n/a	85%
Year 2033 Percent of beaches graded B- and above n/a 5 year rolling average n/a 2035 Goal 85%
2034	n/a	n/a	85%
Year 2034 Percent of beaches graded B- and above n/a 5 year rolling average n/a 2035 Goal 85%
2035	n/a	n/a	85%
Year 2035 Percent of beaches graded B- and above n/a 5 year rolling average n/a 2035 Goal 85%

Year	# of OWTS replacements, upgrades, and removals	Cumulative	2035 Goal
2025	28 in Nassau County and 61 in Suffolk County 89	89	11500
Year 2025 # of OWTS replacements, upgrades, and removals 28 in Nassau County and 61 in Suffolk County 89 Cumulative 89 2035 Goal 11500
2026	n/a	n/a	11500
Year 2026 # of OWTS replacements, upgrades, and removals n/a Cumulative n/a 2035 Goal 11500
2027	n/a	n/a	11500
Year 2027 # of OWTS replacements, upgrades, and removals n/a Cumulative n/a 2035 Goal 11500
2028	n/a	n/a	11500
Year 2028 # of OWTS replacements, upgrades, and removals n/a Cumulative n/a 2035 Goal 11500
2029	n/a	n/a	11500
Year 2029 # of OWTS replacements, upgrades, and removals n/a Cumulative n/a 2035 Goal 11500
2030	n/a	n/a	11500
Year 2030 # of OWTS replacements, upgrades, and removals n/a Cumulative n/a 2035 Goal 11500
2031	n/a	n/a	11500
Year 2031 # of OWTS replacements, upgrades, and removals n/a Cumulative n/a 2035 Goal 11500
2032	n/a	n/a	11500
Year 2032 # of OWTS replacements, upgrades, and removals n/a Cumulative n/a 2035 Goal 11500
2033	n/a	n/a	11500
Year 2033 # of OWTS replacements, upgrades, and removals n/a Cumulative n/a 2035 Goal 11500
2034	n/a	n/a	11500
Year 2034 # of OWTS replacements, upgrades, and removals n/a Cumulative n/a 2035 Goal 11500
2035	n/a	n/a	11500
Year 2035 # of OWTS replacements, upgrades, and removals n/a Cumulative n/a 2035 Goal 11500

1
Baseline established by Chris Eagler

Year	# of sites	# of samples collected	2035 Goal >93 stations sampled
2023	93	983	1,081.30
Year 2023 # of sites 93 # of samples collected 983 2035 Goal >93 stations sampled 1,081.30
2024	133	1398	1,081.30
Year 2024 # of sites 133 # of samples collected 1398 2035 Goal >93 stations sampled 1,081.30
2025	156	1705	1,081.30
Year 2025 # of sites 156 # of samples collected 1705 2035 Goal >93 stations sampled 1,081.30
2026	n/a	n/a	1,081.30
Year 2026 # of sites n/a # of samples collected n/a 2035 Goal >93 stations sampled 1,081.30
2027	n/a	n/a	1,081.30
Year 2027 # of sites n/a # of samples collected n/a 2035 Goal >93 stations sampled 1,081.30
2028	n/a	n/a	1,081.30
Year 2028 # of sites n/a # of samples collected n/a 2035 Goal >93 stations sampled 1,081.30
2029	n/a	n/a	1,081.30
Year 2029 # of sites n/a # of samples collected n/a 2035 Goal >93 stations sampled 1,081.30
2030	n/a	n/a	1,081.30
Year 2030 # of sites n/a # of samples collected n/a 2035 Goal >93 stations sampled 1,081.30
2031	n/a	n/a	1,081.30
Year 2031 # of sites n/a # of samples collected n/a 2035 Goal >93 stations sampled 1,081.30
2032	n/a	n/a	1,081.30
Year 2032 # of sites n/a # of samples collected n/a 2035 Goal >93 stations sampled 1,081.30
2033	n/a	n/a	1,081.30
Year 2033 # of sites n/a # of samples collected n/a 2035 Goal >93 stations sampled 1,081.30
2034	n/a	n/a	1,081.30
Year 2034 # of sites n/a # of samples collected n/a 2035 Goal >93 stations sampled 1,081.30
2035	n/a	n/a	1,081.30
Year 2035 # of sites n/a # of samples collected n/a 2035 Goal >93 stations sampled 1,081.30

Focus Question

Are pathogens decreasing on the coastlines of Long Island Sound?

Answer: Yes, based on the five-year rolling average of beaches graded B- or above from Save the Sound’s Sound Health Explorer, pathogen detection has declined since 2007. However, this average has been relatively constant at 75 to 77 percent for the last five years. In the future, the Partnership will emphasize improving wastewater treatment infrastructure and increasing the scope of nearshore monitoring to meet the improved beach grade goal of 85 percent by 2035. These infrastructure improvements may help to reduce the pathogens impacting Long Island Sound beaches and shellfish areas; and increased monitoring, with wider spatial coverage, will improve the assessment of pathogen impacts on Long Island Sound and its resources.

Measures of Success

Achieve a five-year rolling average of 85 percent of beaches graded B- and above based on beach data from Sound Health Explorer (starting from a baseline of 75.5 percent from 2003-2023); complete 11,500 onsite wastewater treatment systems replacements, upgrades, and removals; and increase the number of samples collected by 10 percent and increase the spatial coverage of monitoring relative to a 2023 baseline (983 samples collected at 93 sites).*

*The Objective’s Measures of Success define reasonable outcomes and ensure that progress towards the Objective can be clearly and precisely tracked over time.

Objective’s Status

Based on the Measures[ of Success, the overall status of this Objective is:

On-Track

Achieve a five-year rolling average of 85 percent of beaches graded B- and above based on beach data from Sound Health Explorer. (On-track)
Complete 11,500 onsite wastewater treatment system replacements, upgrades, and removals. (Behind Schedule)
Increase the number of samples collected by 10 percent and increase the spatial coverage of monitoring relative to a 2023 baseline. (Met Goal)

Indicators’ Status

These indicators provide supporting data and insight into the progress made towards the Objective.

Approved Shellfish Areas

Acres approved

Very Good

Increase

Beach Closures and Advisories

Number of days Long Island Sound beaches are closed

Poor

Increase

Status, Challenges, & Importance

The primary measures of success are to achieve a five-year rolling average of 85 percent of beaches graded B- and above based on beach data from Sound Health Explorer (starting from a baseline of 75.5 percent from 2003-2023); to complete 11,500 onsite wastewater treatment system (OWTS) replacements, upgrades, and/or removals; and increase the number of samples collected by 10 percent and increase the spatial coverage of monitoring relative to a 2023 baseline (983 samples collected at 93 sites).

Status

This objective aims to reduce pathogen contamination from wastewater and stormwater infrastructure and onsite treatment. To track progress, the Partnership tracks three measures: beach grades from the Sound Health Explorer, onsite wastewater treatment systems replaced, upgraded, and removed, and water monitoring for pathogen presence.

Beach Grades

The five-year rolling average of beaches graded B- or above from Save the Sound’s Sound Health Explorer, pathogen detection has declined since 2007 shows recent stability and a slightly increasing trend. This indicates the Partnership is on track to meet the goal of a five-year rolling average of 85 percent of beaches graded B- and above by 2035. The most currentcurrent 5-year average (77%) is slightly above the time series average (75%). In 2024 and 2025, there were lessfewer high-scoring beaches than usual, but in 2025 the grades bounced back up so that 77% of the beaches received grades higher than B-. See details on how Save the Sound compiles beach grades in the data notes at the bottom of this page.While the overall average regional beach grades vary from year to year, recent data is relatively stable since 2019. However, grades declined from 2023 to 2024 across Connecticut and in western Suffolk County but were otherwise constant for other New York beaches.

Unsafe levels of pathogens in the water can be caused by aging wastewater and stormwater infrastructure, polluted runoff from developed land, improperly functioning OWTS, and uncontrolled/untreated runoff from pet and wildlife waste. Furthermore, other environmental influences can impact the concentration of pathogens – increased temperatures can increase bacterial growth and intense rain events flush more pathogenic bacteria into the Sound.

Onsite Wastewater Treatment Systems

The number of Onsite Wastewater Treatment Systemts (OWTS) replaced, upgraded, and removed will is also be tracked to monitor the Partnership’s progress towards this objective to reduce pathogen contamination. In 2025, there were 28 onsite wastewater treatment systems (OWTS) replaced, upgraded, or removed in Nassau County and 61 in Suffolk County. This is a total of 89 projects, which indicates the Partnership is behind schedule to meet the ambitious goal of 11,500 OWTS replacements, upgrades, or removals by 2035. To be on schedule an average of 1,150 system replacements, upgrades, or removals would be needed each year, on average.

Suffolk County cited challenges they faced to stay on track towards the 2069 goal in an August 2026 Newsday article. One challenge mentioned was delays in incorporating a measure intos the sanitary code to require homeowners in certain priority areas to install innovative and alternative on-site wastewater treatment systems when replacing a failing system. Another challenge mentioned was perceived higher installation costs of innovative and alternative systems. The article cites various grants and resources to reduce installation costs to low or no cost to the homeowner.

Sample Collection for Pathogen Monitoring

Another aspect of this objective aims to enhance our understanding and to better inform the management of pathogen contamination through increased monitoring. The Partnership monitors water for the presence of pathogens by testing for indicator bacteria. The presence of indicator bacteria at certain levels is used to presume the presence of pathogens. The Nnumber of samples collected, and temporal and geographic distribution, track progress of this objective.

The Partnership had great success with increasing water sampling for the presence of pathogens in 2025. In 2025, a total of 1,705 samples were collected. This exceeds the goal of increasing the number of samples by 10% relative to a 2023 baseline of 983 samples. Additionally, the Partnership is on track to meet its goal to increase the spatial coverage of monitoring to a baseline of 93 sites; 156 sites were sampled in 2025. It will be important for the Partnership to continue this trend of rigorous sampling to reliably keep track of pathogen contamination in Long Island Sound.

Challenges

Sufficient funding for needed wastewater (including OWTS) and stormwater, upgrades is a major challenge as funding is limited and much of this infrastructure is decades old. It is difficult to pin-point the locations of failing systems as they are diffuse sources. The impacts of the changing climate including increasing temperatures, sea level rise, and more severe storms will further challenge this aging infrastructure.

Importance

The presence of pathogens is a major factor in beach and shellfish area closures. This impacts how people can safely interact with the Sound. Beach closures due to high pathogens means less beach days. The closure of shellfish area limits recreational and commercial shellfish harvesting. and can therefore significantly inhibit some of the major human uses of Long Island Sound if not sufficiently controlled.

Contact

Kelly Streich, CT DEEP, kelly.streich@ct.gov
Hope Savercool, NYSDEC, hope.savercool@dec.ny.gov

Data Notes

The technical explanation of the objective and actions is found in Appendix B of the Comprehensive Conservation and Management Plan.
Save the Sound compiles beach grades for over 200 beaches around Long Island Sound measured against state pathogen criteria for safe swimming. Local health departments collect and analyze samples for fecal indicator bacteria as mandated by recreational swimming beach criteria and permits. This information is available back to 2003 and is found on Save the Sound’s Sound Health Explorer.
Information on the other measures of success, such as the number of onsite wastewater systems removed or upgraded, is available from the Connecticut Department of Energy and Environmental Protection (CT DEEP) and Nassau and Suffolk counties in New York. The numbers and geographic distributions of pathogen samples are available from Save the Sound and the Interstate Environmental Commission.

What's Being Done View Objective and Its Actions

objective

Pathogens

Reduce pathogens and increase monitoring to protect water quality and human health, ensuring safe recreational and commercial use.

Focus Question

Are pathogens decreasing on the coastlines of Long Island Sound?

Measures of Success

Objective’s Status

Indicators’ Status

Status, Challenges, & Importance

Status

Beach Grades

Onsite Wastewater Treatment Systems

Sample Collection for Pathogen Monitoring

Challenges

Importance

Contact

Data Notes

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