Overview

Clean water is also important for our economy. The Cape’s economy is a “blue economy” where our residents, visitors and businesses rely upon clean water and healthy natural resources. The economic benefits of clean water and healthy ecosystems are demonstrated by the fact that coastal tourism and commercial and recreational fishing and shellfishing and their supporting industries bring in more than $1 billion to the local economy. For example, in 2018, tourists visiting Cape Cod spent $1.32 billion that supported 10,844 tourism-related jobs and $357.7 million in wages, and generated $133 million in state and local taxes (Cape Cod Chamber of Commerce).

Commercial and recreational fishing and shellfishing also bring in additional millions of dollars each year. From 2000 – 2004, the average annual value of commercial and recreational shellfishing was $11.4 million. In 2009 alone the value of commercial fishing was $19 million, while the value of commercial fishing for species that eat river herring was over $37 million (NRCS, Cape Cod Water Resources Restoration Project: Why It Matters to Massachusetts Economy). In 2018, the economic value of Cape Cod’s commercial fisheries totaled over $73.6 million, accounting for over 11 percent of the economic value of the Commonwealth’s commercial fisheries (“Port by Port: Profiles and Analysis of the Massachusetts Commercial Fishery“). These numbers do not include the economic contribution from water-focused organizations such as oceanographic institutions and businesses, non-governmental organizations, educational institutions, and laboratories that employ people and provide services and products.

Finally, clean drinking water is critically important for human health. The water we drink comes from Cape Cod’s sole-source aquifer, a vast underground natural reservoir of groundwater. Federal, state, and local laws are designed to protect a sole-source aquifer from pollution. However, as we discuss below, our groundwater, ponds, lakes, estuaries and embayments are all interconnected.

WATER POLLUTION

Most of the Cape’s coastal embayments and many freshwater ponds and lakes are suffering from water pollution, based on years of studies and reports on water quality and water pollution. These studies and reports indicate that the Cape’s waters suffer from pollution due to the following pollutants and pollution sources.

Nutrient pollution: Excess nutrients (nitrogen in coastal waters and phosphorus in fresh water) have caused severe eutrophication and severe ecological damage. Eutrophication refers to the harmful effects of excess nutrients on an aquatic ecosystem, resulting in increased growth of phytoplankton and depletion of oxygen. Excess nutrients in water stimulates the growth of phytoplankton (microscopic algae), which depletes the water of oxygen. Oxygen depletion leads to fish kills and impacts on shellfish and other aquatic life. Excess phytoplankton also causes water to become cloudy, reducing the amount of light in the water column, which impacts the growth of other beneficial aquatic plants such as eelgrass. When algae die, their remains settle to the bottom and decompose, causing more oxygen depletion and releasing nutrients back into the water, feeding the nutrient cycle. Also, the buildup of decaying organic matter on the bottom of ponds, lakes and embayments often results in thick muck that is unhealthy for shellfish, fish and other aquatic organisms.

Many of the Cape’s estuaries and embayments are suffering from eutrophication caused by excess nitrogen, as demonstrated by the Massachusetts Estuaries Project and by the Section 208 Water Quality Management Plan for Cape Cod.

Ponds and lakes are also suffering from eutrophication caused by excess nutrients, in particular phosphorus (Cape Cod Commission, Ponds and Lakes).

On Cape Cod, excess nutrients originate largely from human sources and activities. Excess nitrogen comes from poorly treated wastewater (e.g., Title 5 septic systems) as well as fertilizers used on lawns, gardens, golf courses and farms. Some nitrogen also falls out from the atmosphere in precipitation, and this atmospheric nitrogen largely originates from burning fossil fuels. Excess phosphorus also comes from septic systems that discharge phosphorus into groundwater that enters ponds and lakes, as well as fertilizers used on lawns, gardens, golf courses and farms that is carried into ponds and lakes in stormwater runoff.

Harmful bacteria include bacteria that originate from fecal wastes (humans and/or animals). Examples of fecal bacteria are Escherichia coli (E. coli) and enteric bacteria. Fecal bacteria can cause illness in both humans and animals. On Cape Cod, most fecal bacteria contamination originates from domestic animals and wildlife. Failed septic systems (including flooded septic systems) are another source of bacteria. Bacteria are carried into water by stormwater runoff. State and federal water quality standards limit the amounts of fecal bacteria that can be present in waters where swimming and shellfishing are conducted. Swimming beach water quality is monitored by Barnstable County. The Massachusetts Division of Marine Fisheries monitors water quality in shellfish beds and limits shellfishing to waters that meet a stringent water quality standard for fecal bacteria.

Harmful algal and cyanobacteria blooms include toxic red tides in coastal waters and toxic cyanobacteria blooms in freshwater ponds and lakes. In coastal waters, red tide is the common name for several species of toxic phytoplankton, including toxic dinoflagellates. Shellfish that ingest such toxic phytoplankton become toxic themselves, posing a threat to humans who eat contaminated shellfish and impacting the shellfishing industry. In freshwater, harmful cyanobacteria that produce toxins thrive in nutrient-rich and warm waters. APCC’s Cyanobacteria Monitoring Program has documented cyanobacteria blooms in dozens of ponds throughout the Cape and we anticipate that this will be an increasing problem as nutrient pollution continues and the climate warms. This year is the third year that APCC has incorporated cyanobacteria monitoring data into our grading system for freshwater ponds as another indicator of nutrient pollution.

Mercury pollution occurs in waters throughout the Northeast. As of July 2022, the Massachusetts Department of Public Health listed 32 ponds and lakes on Cape Cod with fish consumption advisories that warn people (i.e., children under 12, pregnant women, nursing mothers, women of childbearing age, and the general public) to limit or avoid eating fish from that lake due to mercury pollution (MA DPH Fish Consumption Advisories). Mercury pollution is caused by fallout of mercury from the atmosphere, which originates from coal-burning fuel plant emissions. Incineration of medical wastes and municipal wastes also contributes mercury to the atmosphere. Our assessment does not address mercury pollution, but the State of the Waters; Cape Cod website provides information on mercury pollution and state fish consumption advisories for freshwater lakes and ponds on Cape Cod.

Emerging contaminants and pharmaceutical compounds have been found both in groundwater and surface water throughout Cape Cod. This group of pollutants contains a wide variety of compounds, including endocrine-disrupting compounds, pharmaceutical drugs (including antibiotics), insect repellant, flame retardant, fluorinated compounds and PFAS (per- and polyfluoroacetate substances). The Silent Spring Institute has been monitoring the Cape’s waters’ emerging contaminants. The Center for Coastal Studies and Silent Spring Institute also found pharmaceutical compounds in Cape Cod Bay and in groundwater near septic systems, pointing to septic systems as the source of these pharmaceutical compounds.

PFAS (per- and polyfluoroacetate substances) are manmade chemicals used widely in diverse items (e.g., fireproof clothing, non-stick pans, stain-and-waterproof fabrics, fire-fighting foam, dental floss, cleaning products, paints, electronics manufacturing and other industries and household products). PFAS are long-lasting compounds that have been found worldwide in humans, wildlife, water, soil, and the air. PFAS have been found in Cape Cod water supplies, groundwater, and ponds (in 2022, six of the 32 ponds which had fish consumption advisories due to mercury also had fish consumption advisories due to PFAS). PFAS compounds have been linked to human health impacts such as developmental disorders, immune system disorders, thyroid hormone disruption and cancer. Information on PFAS is provided in APCC’s PFAS Primer. New state regulations limiting PFAS6 in drinking water came into effect in 2021 and were applied in our drinking water grades for this report.

HOW WE GRADED WATER QUALITY

To help people understand where water quality is acceptable vs. unacceptable, APCC has created this State of the Waters: Cape Cod project and website to collect existing information on water quality and translate it into easily understood terms by grading water quality. This website is a key means of collecting and distributing information to the public. Our intent is to guide public policy and investment in restoration and protection efforts.

Using existing data, APCC grades the following water resources:

• Coastal waters in embayments and estuaries;
• Freshwater ponds and lakes; and
• Public water supplies for drinking water (i.e., drinking water after it is treated by the public water supplier and before it is distributed to consumers).

APCC uses three grading systems, one system for grading coastal waters, a second system for grading freshwater ponds and lakes, and a third system for grading public water supplies that provide drinking water. Each of the grading systems scores water quality parameters. The scores are then translated into grades. APCC uses grading systems that meet the following criteria:

• Are scientifically sound;
• Have been used before to evaluate water quality;
• Use key water quality parameters to evaluate water quality problems;
• Allow for annual updating using the most recent available data;
• Are easily understood and can be replicated by others (e.g., it does not require complex methods, modeling or software); and
• Evaluates the most pressing water quality problems.

In order to provide the most up-to-date assessment feasible, each year the grades are updated on a moving basis by dropping older data and adding newer available data through the previous year. The grading systems are explained below.

• Establish baseline water quality;
• Characterize and identify sources of pollution;
• Document long-term environmental trends in water quality;
• Evaluate the relative success of cleanup efforts;
• Facilitate implementation of management efforts in the CCMP; and
• Evaluate the appropriateness of the Buzzards Bay Project’s recommended nitrogen limits.

In addition to the BBC, the Eutrophic Index has also been used by the Center for Coastal Studies, the Pleasant Bay Alliance, and the town of Chatham to evaluate nitrogen pollution in Buzzards Bay, Cape Cod Bay and coastal waters around the Cape, Pleasant Bay, and Chatham. The Eutrophic Index is considered by practitioners to be a well-tested method.

The Eutrophic Index scores parameters that measure the degree of eutrophication are: dissolved oxygen saturation, water clarity (measured using either Secchi disk or a turbidity meter), chlorophyll, dissolved inorganic nitrogen (DIN), and total organic nitrogen (TON). Water quality data for these parameters is used to calculate a numerical score that indicates the degree of eutrophication. To translate scores into an assessment of water quality, the BBC uses three categories to “grade” scores: scores of 65 to 100 indicate Good water quality; scores between 35 and 65 indicated Fair water quality; and scores below 35 indicate Poor water quality.

Following the BBC’s method, APCC calculates numerical Eutrophic Index scores for water quality from stations in coastal embayments and coastal waters around Cape Cod. However, APCC “grades” the numerical scores for water quality from individual stations in a manner that differs from the BBC. APCC assigns scores to two grading categories based on whether they indicate acceptable water quality or unacceptable water quality. The two grading categories are chosen to indicate the type of action needed to protect or restore water quality.

Grading coastal water quality at coastal stations:

EI scores greater than 65 (> 65) are graded as: “Acceptable: requires ongoing protection.”

EI scores of 65 or below (≤ 65) are graded as: “Unacceptable: requires immediate restoration.”

Waters that are graded as “Acceptable: requires ongoing protection” are waters that are healthy and free of excess nutrients. These waters need ongoing protection to remain healthy and free of pollution.

Waters that are graded as “Unacceptable: requires immediate restoration” are waters that are suffering from excess nutrients. These waters need immediate restoration in order to improve water quality.

Grading water quality in coastal embayments:

APCC has taken the additional step of identifying embayments where at least one monitoring station had Unacceptable water quality and graded these embayments as “Unacceptable: requires immediate restoration.” Embayments where all monitoring stations had Acceptable water quality were graded as “Acceptable: requires ongoing protection.” This approach to grading embayments provides a clear summary of which embayments have portions with poor water quality that require restoration vs. embayments with good water quality that require protection.

Grading Ponds and Lakes

Method 1: Carlson Trophic Index

To grade water quality in freshwater ponds and lakes, APCC uses two methods. The first method is the Carlson Trophic Index (CTI) which evaluates the trophic state of the water body in terms of three important parameters for freshwater quality: total phosphorus, chlorophyll, and water transparency. The Carlson Trophic Index was developed in 1996 to assess the trophic state of a freshwater pond or lake, where trophic state refers to the ecological response (algal biomass) to nutrients (Carlson, 1977). Since then, it has been widely used for evaluating freshwater ponds and lakes. The Carlson Trophic Index is analogous to the Buzzards Bay Eutrophic Index in that it evaluates the degree of eutrophication in fresh water.

The Carlson Trophic Index uses a numerical scoring system to evaluate pond trophic status. Using the Carlson Trophic Index, a eutrophic to hypereutrophic pond with high nutrient concentrations would be characterized by high concentrations of algae, algal scums, poor water clarity due to dense algae, low to no dissolved oxygen, and CTI scores between 50 and 100. At the opposite end of the spectrum, an oligotrophic pond with low nutrient concentrations would be characterized by clear, well-oxygenated water, healthy aquatic plants, little to no algal growth, and CTI scores between 0 and 40. A mesotrophic pond with intermediate nutrient concentrations would be characterized by moderately clear water, intermediate amounts of aquatic plants and algae, low dissolved oxygen during the summer, and CTI scores between 40 and 50.

APCC uses a grading system that assigns the following grades to Carlson Trophic Index (CTI) scores:

CTI scores of less than 50 (< 50) are graded as: “Acceptable: requires ongoing protection.”

CTI scores of 50 or above (≥ 50) are graded as: “Unacceptable: requires immediate restoration.”

Ponds that are graded as “Acceptable: requires ongoing protection” are ponds that are healthy and free of excess nutrients. These ponds need ongoing protection to remain healthy and free of pollution.

Ponds that are graded as “Unacceptable: requires immediate restoration” are ponds that are suffering from excess nutrients. These ponds need immediate restoration in order to improve water quality.

Data quality for CTI scoring: Many datasets for pond water quality for Cape Cod ponds are older, i.e., at least five years old or more. Using older data to grade ponds would cause grades to reflect conditions that existed at the time when water samples were collected and analyzed. Conditions in ponds may have changed since such older data were collected. In order to provide an evaluation of recent pond conditions, this project screens out older data on a moving basis each year. For 2022 grading of ponds, APCC screened out pond data older than 2017 and required at least three years of data from 2017 on, as well as data for all three CTI parameters (chlorophyll, total phosphorus, and Secchi disk depth). Application of these stringent data quality requirements for grading resulted this year in only 68 ponds with sufficient water quality data to enable grading using the Carlson Trophic Index. As the Cape has 890 ponds, this points out the severe shortage of recent Cape-wide pond monitoring data to inform pond management and protection measures.

Method 2: Using Cyanobacteria Monitoring Data

Since 2018, APCC has been monitoring cyanobacteria and cyanobacteria blooms in over 100 freshwater ponds on Cape Cod. Cyanobacteria blooms occur when there are sufficient nutrients to stimulate growth of these photosynthetic bacteria. Warmth and sunlight are other factors that stimulate cyanobacteria growth, but in the absence of nutrients or when nutrient concentrations are very low, cyanobacteria growth is generally minimal. Cyanobacteria blooms therefore represent another indicator of nutrient enrichment in freshwater ponds.

APCC’s Cyanobacteria Monitoring Program uses an EPA-approved protocol developed by EPA for the Cyanobacteria Monitoring Collaborative and refinements added under the guidance of Dr. James Haney (emeritus professor, University of New Hampshire) and Nancy Leland of Lim-tex, Inc. (Leland and Haney, 2018; Leland, Haney, Conte, Malkus-Benjamin and Horseley, 2019). The EPA protocol utilizes a combination of field observations, microscopy and fluorometry to analyze samples from freshwater lakes and ponds for cyanobacteria. Data collected includes photographs and field observations, microscopy to identify composition and dominance of cyanobacteria genera, and concentrations of phycocyanin and chlorophyll pigments indicative of the biomass of cyanobacteria vs. biomass of other algae and phytoplankton, respectively. By monitoring biweekly from May to October, APCC tracks changes in cyanobacterial composition, dominance and abundance throughout the season. At this sampling frequency, it is often possible to forecast when cyanobacteria blooms may be about to form or when cyanobacteria concentrations may lead to cyanobacteria toxin concentrations approaching harmful levels. APCC then increases the frequency of testing to inform town officials to be aware of potential threats and to plan for proactive management actions to protect public safety. To learn more, visit APCC’s Cyanobacteria Monitoring Program.

The scarcity of recent pond water quality data led APCC in 2020 to adopt a second method of grading ponds using cyanobacteria monitoring data to provide an additional measure of pond health. The use of cyanobacteria data helps to fill the gap in freshwater pond data by providing a different measure of trophic status. APCC’s cyanobacteria grading system utilizes our three-tiered risk warning system for assigning monitored cyanobacteria concentrations into “Low,” “Moderate” and “High” risk tiers, which describe potential risks in terms of exposure to children, pets, exposure during recreational activities, toxin concentrations, and presence of visible cyanobacteria blooms. To grade ponds using cyanobacteria risk tiers, the tiers are assigned into “Acceptable” or “Unacceptable” grades according to the risk definitions. The previous year’s monitoring results are used. The highest risk tier that is documented in a pond in a monitoring season is used to assign a grade.

Cyanobacteria risk tiers and grading system used this year:

This year, APCC revised our risk tier definitions for the 2022 Cyanobacteria Monitoring Program. The revisions in risk definitions reflect input from local and state public health officials and scientists, incorporation of state limits for cyanobacteria toxin in recreational waters, and a new regional capability for cyanobacteria toxin testing at the Barnstable County water quality lab. The 2022 risk tiers are given below.

Acceptable (“Low” risk): No concerning cyanobacteria results at the time and place of sampling. To the best of APCC’s knowledge and based on our monitoring results, regular recreational usage of the pond is safe with respect to cyanobacteria and toxins. Map color is blue. Formerly the Low Warning Tier.

Potential for Concern (“Moderate” risk): Monitoring results or the presence of cyanobacteria scum at the time and place of sampling indicate a potential for increased risk for exposure to cyanobacteria toxins approaching, but below, state standards. Conditions do not yet warrant the posting of a recreational human health advisory according to guidelines from the Massachusetts Department of Public Health (MDPH). While these conditions pose low health risks to adults, risks are higher for children or pets based on lower body mass, particularly if contaminated water is incidentally ingested. Children may inadvertently consume pond water while swimming and pet exposure can result from drinking or ingesting pond water or from grooming after swimming. Map color is yellow. Map color yellow with crosshatching indicates a municipal pet advisory has been issued. Formerly the Moderate Warning Tier.

Use Restriction Warranted (“High” risk): Monitoring results at the time and place of sampling indicate the pond is unsafe for recreation by humans and pets based on one or more of the following criteria: 1) presence of microcystin at or above state standards (8 ppb microcystin) as described in MDPH guidance, 2) presence of significant cyanobacteria scum layers according to MDPH guidance, 3) a municipal health agent issues a closure for any other reason related to cyanobacteria. Recreational risk to adults is moderate following exposure. Recreational risks are especially high for children and pets following exposure through accidental ingestion of contaminated water. Children may inadvertently consume pond water while swimming and pet exposure can result from ingestion or directly drinking pond water or from grooming after swimming. Due to lower body masses, children and pets are more susceptible to cyanobacteria risks than adults. Map color is red. Map color red with crosshatching indicates a municipal advisory has been issued. Formerly the High Warning Tier.

The 2022 cyanobacteria grading system for 2021 cyanobacteria data is given below:

Cyanobacteria levels in the “Low” and “Moderate” risk tiers were graded as: “Acceptable: ongoing protection is needed”; and

Cyanobacteria levels in the “High” risk tier were graded as “Unacceptable: requires immediate restoration.”

Combined Pond Grading System

As in previous years, APCC’s combined pond grading system utilizes available Carlson Trophic Index grades and cyanobacteria grades, as follows:

1. Carlson Trophic Index scores and grades for ponds were calculated for ponds where water quality data from 2017 on was available, and where at least three years of data were available for all three CTI parameters (chlorophyll, total phosphorus, and Secchi disk depth).
2. Cyanobacteria monitoring data from 2021 were used to grade ponds using APCC’s revised cyanobacteria risk tiers and grading system described above:
   1. Ponds with cyanobacteria levels in the “High” risk tier were graded as “Unacceptable: requires immediate restoration”;
   2. Ponds with cyanobacteria levels in the “Low” and “Moderate” risk tiers were graded as “Acceptable: requires ongoing protection.”
3. If a pond had both Carlson Trophic Index grades and Cyanobacteria grades:
   1. The pond was graded as “Acceptable: requires ongoing protection” only if both grades were Acceptable;
   2. The pond was graded as “Unacceptable: requires immediate restoration” if at least one of the grades was Unacceptable.
4. If a pond had only one grade (i.e., Carlson Trophic Index grade or Cyanobacteria grade), that grade was used as the sole determinant of the overall pond grade.

Grading Public Water Supplies of Drinking Water

The grading system for drinking water is based on a modification of a method developed by the Natural Resources Defense Council (NRDC) to grade drinking water. The NRDC grading system evaluates three areas of drinking water: water quality and compliance, source water protection, and right-to-know compliance. APCC evaluates water quality and compliance of public water supplies after treatment and before distribution to consumers, the so-called “finished water.” This represents the underlying quality of the public water supply before it is distributed to customers, not the quality of the water as it comes out of the tap, which can be affected by pipes and plumbing in the distribution system and in homes and businesses. APCC evaluates public water supplies in this manner because underlying water quality represents the first line of defense in ensuring safe drinking water supplies and because many water protection measures are aimed at protecting source water quality.

To grade Cape Cod public water supplies, APCC uses publicly available Consumer Confidence Reports (CCRs) for the previous year to determine if water quality met existing state and federal drinking water standards (i.e., Maximum Contaminant Levels, or MCLs).

In the 2019 and 2020 State of the Waters report, APCC applied a two-level grading system based on whether public water supplies met all existing state and federal drinking water standards were met in the previous year. If a public water supply met all existing state and federal drinking water standards, it was graded as “Excellent”; if not, it was graded as “Poor.” In the 2019 and 2020 reports, all public water suppliers met all existing state and federal drinking water standards. Resulting grades were all “Excellent.”

In 2021, the grading system was revised to a three-level grading system: “Excellent,” “Good,” and “Poor.” The change was based on the need to report on varying degrees of potential risk posed by violations, e.g., ranging from one or two violations of the total coliform standard followed by compliance, to several violations of two drinking water standards occurring at different locations on different dates requiring issuance of a boil-water order representing a high potential risk level. APCC felt it was important to distinguish the different levels of potential risk. The 2021 three-level grading system was as follows: “Excellent”: Public water supply met all existing state and federal health and reporting standards (unchanged); “Good”: Public water supply had one or more exceedances of the total coliform MCL and/or no more than one violation of an existing state and/or federal standard that posed a risk to public health and that violation was neither chronic nor repeated; and “Poor”: Public water supply had two or more violations of an existing state and/or federal standard that posed a risk to public health or a violation that was repeated or persisted through more than one sampling round.

Grading system used this year (2022)

The major change in drinking water regulation since last year’s report involved the new state drinking water standard for PFAS6 that went into effect in April 2021 (MassDEP PFAS Drinking Water Regulation Quick Reference Guide). PFAS refers to per- and polyfluoroalkyl substances, a family of manmade chemicals used in industry and consumer products worldwide since the 1950s to manufacture stain-resistant, water-resistant, and non-stick products. Thousands of PFAS compounds are known. PFAS6 refers to the sum of six per- and polyfluoroalkyl substances. The new PFAS6 standard is 20 parts per trillion (ppt) based on the average of the monthly samples over a quarter. If any one sampling location is in violation, then the PWS is in violation. If any sample result would cause the quarterly average to exceed the PFAS6 MCL, the PWS is immediately in violation and begins compliance actions.

For grading this year, APCC used the three-level grading system but clarified the definitions as follows:

Excellent: In 2021, finish water met all existing state and federal health and reporting standards.

Good: In 2021, finish water had one or more exceedances of the Total Coliform MCL and/or no more than one violation of an existing state or federal standard that posed a risk to public health and that violation was neither chronic nor repeated.

Poor: In 2021, finish water had violations of two or more existing state and/or federal standards that posed a risk to public health or a violation that was repeated or persisted through more than one sampling round.

In addition, APCC identified PWSs that had detectable PFAS6 but met the state standard with an asterisk (*).

Regional data sources. These sources provided data covering multiple embayments or large areas of the Cape. Sources of coastal data are also shown in Figure 1.

• Association to Preserve Cape Cod: 2021 cyanobacteria monitoring data for freshwater ponds located in the towns of Barnstable, Bourne, Brewster, Chatham, Dennis, Eastham, Falmouth, Harwich, Mashpee, Orleans, Provincetown, Sandwich, Truro, Wellfleet, and Yarmouth;
• Partners who assisted APCC with cyanobacteria sample collection included: Brewster Ponds Coalition, Falmouth Water Stewards, Friends of Chatham Waterways, Friends of Long Pond Marstons Mills, Orleans Ponds Coalition, Oyster Pond Environmental Trust, the towns listed above, and other organizations and individuals.
• Barnstable Clean Water Coalition: coastal water quality data for stations located in the Three Bays embayment and pond water quality data;
• Buzzards Bay Coalition: Eutrophic Index scores for coastal stations and embayments located in Buzzards Bay along the coasts of Falmouth and Bourne;
• Center for Coastal Studies: coastal water quality data for stations located in embayments on Cape Cod Bay, Nantucket Sound and Vineyard Sound;
• Cape Cod Commission: coastal and pond water quality data collected by and for the Cape Cod Regional Water Quality Database, a project to collect and make publicly available all water quality monitoring data for the Cape. The project was funded by the EPA Southeast New England Coastal Watershed Restoration Program (EPA SNEP);
• Cape Cod Commission and University of Massachusetts at Dartmouth, School of Marine and Atmospheric Science and Technology (SMAST): Pond and Lake Stewards (PALS) data for pond water quality (note: most of the pond data provided by towns and organizations listed below was provided by PALS and SMAST for the towns and organizations);
• Pleasant Bay Alliance: coastal Eutrophic Index scores for stations located in Pleasant Bay;
• Waquoit Bay National Estuarine Research Reserve (WBNERR): coastal water quality data for stations located in Waquoit Bay.

Municipal data sources:

• Town of Barnstable: coastal and pond water quality data;
• Town of Brewster: pond water quality data for one pond;
• Town of Chatham: coastal Eutrophic Index scores for coastal stations in Chatham and Pleasant Bay;
• Town of Eastham: coastal and pond water quality data;
• Town of Harwich: coastal and pond water quality data;
• Town of Mashpee: coastal and pond water quality data;
• Town of Orleans: coastal and pond water quality data.

Data quality

In order to evaluate recent water quality conditions, APCC applies data quality standards that include using the most recent and complete data available. Data quality requirements for grading water quality data are summarized below. Data sets can be found under Resources.

Coastal water quality data: For this 2022 report, APCC collected the most recent available coastal water quality data up to and through 2021 from the data sources listed above. Our criteria for grading coastal water quality data included at least five years of data from 2017 on (e.g., 2017, 2018, 2019, 2020, and 2021). There were two exceptions: Harwich coastal water quality data where data from 2016, 2017, 2018, 2019, and 2021 were used for grading monitoring in 2020 was suspended due to the COVID-19 pandemic; and WBNERR where data for 2016-2020 were utilized as 2021 data were not available.

Freshwater pond and lake water quality data: Since 2000, the Cape Cod Ponds and Lakes Stewardship Program (PALS) has worked with volunteers and organizations who monitor many ponds across the Cape. The PALS program was developed by the Cape Cod Commission, APCC and SMAST, in coordination with organizations and towns that monitor water quality on an annual snapshot basis. Other pond associations and organizations have gathered a considerable amount of data with their member volunteers. For this 2022 report, APCC collected pond water quality data from the sources listed above. Our criteria for grading pond water quality data included at least three years of data from 2017 on, and data for all three Carlson Trophic Index parameters (chlorophyll, transparency, and total phosphorus).

Cyanobacteria data for ponds and lakes: For this 2022 report, APCC utilized 2021 cyanobacteria monitoring data collected by APCC’s Cyanobacteria Monitoring Program. Cyanobacteria monitoring data were collected according to an EPA-approved Quality Assurance Project Plan for cyanobacteria monitoring.

Drinking water and public water supplies: For this 2022 report, APCC collected each town’s public-right-to-know reports for 2021 monitoring results, also known as the Consumer Confidence Reports (CCRs) for drinking water. CCRs are posted on each town’s website. Links to the CCRs are provided under Resources, in the popups on the interactive viewer, and in our Public Water Supplies grading sheet. APCC used the CCRs to grade water quality and compliance with existing drinking water regulations. In some cases, APCC contacted water superintendents for additional information.

RESULTS

Our 2022 grades for coastal embayments and stations, freshwater ponds and lakes, and public water supplies are provided as maps and in the spreadsheets found here. Our findings are described below.

Coastal embayments and coastal stations

Coastal embayments:

• The number and percentage of Unacceptable embayments increased to 43 this year, representing 90% of graded embayments. Last year in our 2021 report, 41 embayments or 87% were Unacceptable. In our 2020 report, 38 embayments or 79% were Unacceptable. In our 2019 report, 32 embayments or 68% were Unacceptable. Over the past four years of the State of the Waters reporting, the number of Unacceptable embayments has steadily increased.
• The number and percentage of Acceptable embayments decreased to five this year, representing 10% of graded embayments. Last year in our 2021 report, six or 13% of graded embayments were Acceptable. In our 2020 report, 10 of 48 embayments or 21% were Acceptable. In our 2019 report, 15 of 47 embayments or 32% were Acceptable. Over the past four years of the State of the Waters reporting, the number of Acceptable embayments has steadily decreased.
• There were 48 embayments graded this year, compared to 47 embayments graded in 2021, 48 in 2020, and 47 in 2019.
• The new Unacceptable embayment this year is the Pamet River on Cape Cod Bay.
• As in 2021, all embayments on Nantucket Sound were Unacceptable, all embayments in Buzzards Bay were Unacceptable with the exception of Quissett Harbor, and Pleasant Bay and Nauset Estuary were Unacceptable.
• Cape Cod Bay continued to have the largest number of Acceptable grades (three) but the Pamet River embayment became Unacceptable.
• There were no embayments that improved from Unacceptable to Acceptable.

Coastal stations:

• Coastal stations had similar numbers and percentages of Unacceptable stations compared to previous years, with over two-thirds of stations graded as Unacceptable. There were 131 Unacceptable coastal stations, representing 69% of graded stations. In our 2021 report there were 133 Unacceptable stations or 68% of graded stations. In our 2020 report there were 106 Unacceptable stations or 70% of graded stations. In our 2019 report there were 98 Unacceptable stations or 64% of graded stations.
• There were similar numbers and percentages of Acceptable stations compared to previous years, with the percentage of Acceptable stations less than one-third of graded stations. There were 60 Acceptable coastal stations, representing 31% of graded stations. In our 2021 report there were 64 Acceptable stations or 32% of Acceptable stations. In our 2020 report there were 46 Acceptable stations or 30% of graded stations. In our 2019 report there were 54 Acceptable stations or 36% of graded stations.
• There were 191 coastal stations graded this year, reflecting a slight decrease from 2021 when there were 197 coastal stations graded. However, the numbers of coastal stations graded this year and last year were greater than the numbers of coastal stations graded in 2019 and 2020 when there were 152 coastal stations with sufficient data to grade.

Ponds

• This year, 151 ponds had sufficient water quality data and/or cyanobacteria data to enable grading, representing an increase over the number of ponds with sufficient data from previous years (i.e., 109 ponds in 2021, 93 in 2020, and 149 in 2019). However, 151 ponds represents only 17% of the Cape’s 890 freshwater ponds, indicating that there is an ongoing shortage of recent data for grading most of the Cape’s ponds.
• Over one-third of all graded ponds were Unacceptable, i.e., there were 59 Unacceptable ponds or 39% of all graded ponds. In our 2021 report last year there were 38 Unacceptable ponds representing 35% of graded ponds. In our 2020 report there were 39 Unacceptable ponds or 42% of all graded ponds. In 2019 there were 58 Unacceptable ponds or 39% of all graded ponds (Table 4).
• Nearly two-thirds of graded ponds were Acceptable, i.e., there were 92 Acceptable ponds representing 61% of graded ponds. Last year, there were 71 Acceptable ponds or 65% of Acceptable ponds. In 2020, there were 54 Acceptable ponds representing 58% of graded ponds. In 2019, there were 91 Acceptable ponds or 61% of graded ponds (Table 4).
• Sixty-eight ponds had sufficient water quality data to grade them using the Carlson Trophic Index, compared to only 36 ponds last year. Of these ponds, 37 or 54% were Acceptable and 31 or 46% were Unacceptable.
• One hundred and twenty-eight ponds were graded using 2021 cyanobacteria monitoring data. Of these, 93 ponds (72%) were Acceptable and 36 ponds (28%) were Unacceptable (Tables 4, 5). The use of cyanobacteria data enabled an additional 83 ponds to be graded.
• Only 46 ponds had both Carlson Trophic Index and Cyanobacteria grades. Of these ponds with dual grades, 23 ponds had Acceptable grades, and 15 ponds had Unacceptable grades.
• The percentages of Acceptable vs. Unacceptable grades for ponds graded using either the Carlson Trophic Index or cyanobacteria were as follows: 54% of ponds with CTI grades were Acceptable compared to 72% of ponds with cyanobacteria grades of Acceptable. Likewise, 46% of ponds with CTI grades were Unacceptable compared to 28% of ponds with cyanobacteria grades of Unacceptable. More data are needed to determine whether the differences are incidental or reflect a more fundamental difference.
• Towns with sufficient pond water quality data to enable grading using the Carlson Trophic Index included: Barnstable (33 ponds); Orleans (12 ponds); Eastham (9 ponds); Harwich (8 ponds); Mashpee (5 ponds); and Brewster (1 pond).
• Towns with 2021 cyanobacteria monitoring data for ponds included: Barnstable (27 ponds); Bourne (2 ponds); Brewster (22 ponds); Chatham (5 ponds); Dennis (4 ponds); Eastham (7 ponds); Falmouth (16 ponds); Harwich (9 ponds); Mashpee (5 ponds); Orleans (4 ponds); Provincetown (2 ponds); Sandwich (7 ponds); Truro (2 ponds); Wellfleet (8 ponds); and Yarmouth (10 ponds).

Public Water Supplies

Grades for public water supplies are summarized below and shown on the map below.

• A total of 20 public water supplies were graded for the quality of their finish water. Sixteen public water supplies on the Cape had “Excellent” water quality, meaning that they met all state and federal drinking water standards: Barnstable COMM, Barnstable Fire District, Cotuit Water Department, Hyannis Water System, Bourne Water District, North Sagamore Water District, Town of Brewster Water Department, Town of Chatham Department of Public Works Water Division, Town of Dennis Water District, Town of Eastham Water Department, Town of Falmouth Water Department, Town of Harwich Water Department, Mashpee Water District, Town of Orleans Water Department, Town of Provincetown Water Department, and Town of Sandwich Water District.
• However, of the 16 public water suppliers with “Excellent” grades, 10 had detectable levels of PFAS6 but met the new state standard for PFAS6 that became effective in 2021. The ten PWSs were: Barnstable COMM, Barnstable Fire District, Cotuit Water Department, Hyannis Water System, Bourne Water District, Town of Chatham DPW Water Division, Town of Dennis Water District, Town of Falmouth Water Department, Mashpee Water District, and Town of Sandwich Water District.
• Two PWSs were graded as having “Good” water quality, based on their detection of total coliform bacteria in finish water: Buzzards Bay Water District, and Town of Wellfleet Municipal Water System. The presence of total coliform bacteria is used as an indicator that harmful enteric bacteria (e.g., E. coli) may be present. Both PWSs followed up with appropriate response measures and did not detect E. coli.
• Two PWSs were graded as “Poor” due to violations of two or more drinking water standards and several violations at different locations: Otis Air National Guard (Total Coliform and E. coli requiring issuance of a boil water order), and the Town of Yarmouth Water Department (Enterococci, and PFAS6).

For more information on PFAS, see APCC’s PFAS Primer .

Discussion

This is the fourth annual report on the State of the Waters: Cape Cod, which provides an assessment of water quality in coastal embayments, freshwater ponds, and public water supplies using the most recent available data. Collectively these annual reports show that the Cape’s coastal waters and freshwater ponds continue to suffer from eutrophication due to excess nutrients, primarily from septic systems (see map below). In contrast, public water supplies were generally “Excellent” or “Good”, but the two “Poor” exceptions indicate that E. coli bacteria or PFAS6 contamination of finish water occurred, which threatens public health. This report also covers the first year (2021) in which new state regulations limiting PFAS6 concentrations in drinking water came into effect. While PFAS6 was detected in 11 of the 20 public water supply systems that serve Cape Cod, 10 of these met the new DEP drinking water regulations for PFAS6. The widespread detection of PFAS6 in public water supplies calls for ongoing monitoring as well as planning and implementation of effective treatment methods.

Coastal embayments and stations

This year, the majority of Cape Cod’s coastal embayments (90%) were Unacceptable, an increase from previous years. Over the past four years of State of the Waters reporting, the number of Unacceptable embayments has steadily increased. Conversely, the number of Acceptable embayments has steadily decreased over the past four years, reaching a low of 10% of embayments this year. As in previous years, over two-thirds of the Cape’s 191 coastal stations had Unacceptable water quality, and less than one-third had Acceptable water quality, similar to results from previous years. These results show that coastal eutrophication in embayments continues and is expanding.

A number of towns have made significant steps toward managing nutrients by approving construction of modern wastewater treatment projects. While embayment water quality has yet to improve as a result, as these projects are implemented over the next few years the region should begin to see lower nutrient loadings that should be reflected in improving water quality in selected embayments.

Ponds

This year, over one-third of the 151 ponds graded were Unacceptable and nearly two-thirds of ponds graded were Acceptable. Despite the increase in the number of ponds with sufficient data to enable grading, these percentages are similar to percentages in previous years. Also, despite the increase in the number of ponds with sufficient data, there is still a drastic shortage of recent pond data, as 151 ponds represents only 17% of the Cape’s 890 freshwater ponds and lakes.

As APCC’s monitoring has expanded, much has been learned about the scope of the impairment of ponds. While lacking a sufficiently robust and lengthy data record upon which to base trend analyses, it appears that based on recent data, approximately one-third of graded ponds achieve Unacceptable status in any given year, and that there is considerable variability from year to year in which ponds trigger that designation. While the conditions representing impairment exist in many ponds, perhaps a majority of ponds Cape-wide, the actual confluence of events that drive poor water quality conditions in any given pond in a particular year remain hard to predict given the lack of detailed and multi-year data.

A comprehensive review and assessment of overall pond health is also hampered by data quality issues. To grade water quality, APCC uses the Carlson Trophic Index, an index of water quality that describes the trophic status of a water body based on total phosphorus, chlorophyll and transparency, i.e., it is a measure of phytoplankton productivity due to nutrient loading where phytoplankton include algae and cyanobacteria). Many pond data are older, e.g., five years old or more. Using older data to grade ponds would cause grades to reflect conditions that existed at the time when water samples were collected and analyzed. Conditions in ponds may have changed since these older data were collected. This year, APCC screened out pond data older than 2017 and ponds with less than three years of data collected. Using these more stringent requirements for grading resulted in only 68 ponds having sufficient water quality data to enable grading using the Carlson Trophic Index. This points out the severe shortage of more recent Cape-wide pond monitoring data to inform pond management and protection measures.

To help fill the gap in freshwater pond data, APCC utilized the results of our cyanobacteria monitoring program. Since 2018, APCC has been monitoring cyanobacteria and cyanobacteria blooms in dozens of freshwater ponds on Cape Cod. Cyanobacteria blooms occur when there are sufficient nutrients to stimulate growth of these photosynthetic bacteria. Warmth and sunlight are other factors that stimulate cyanobacteria growth, but in the absence of nutrients or when nutrient concentrations are very low, cyanobacteria growth is minimal. Cyanobacteria blooms represent another way to assess phytoplankton productivity due to nutrient enrichment in freshwater ponds and is complementary to the use of the Carlson Trophic Index. Of the 68 ponds with sufficient water quality data to be graded using the Carlson Trophic Index, 46% were Unacceptable. Of the 129 ponds graded using cyanobacteria tiers, 28% were Unacceptable. The differences in percentages of Unacceptable grades between the two grading systems likely reflects the fact that they represent two different ways to measure eutrophication: The Carlson Trophic Index measures overall phytoplankton productivity while the cyanobacteria grade measures cyanobacteria productivity where cyanobacteria represent a component of phytoplankton populations.

Public Water Supplies

The majority of public water supplies (16 of 20) met all existing state and federal drinking water quality standards and were graded as “Excellent.” Several exceptions indicate that bacterial contamination can occur and can threaten public health. The need to issue a boil-water order to protect public health from E. coli resulted in a grade of “Poor” for one public water system (Otis Air National Guard). The town of Wellfleet’s public water system, which was graded “Poor” last year for the same reason, was graded as “Good” this year, as it had improved. Strict adherence to prevention of pollution, monitoring, follow-up actions, treatment, maintenance, and public awareness should address such bacterial issues and protect public health.

This report also covers the first year (2021) in which new state regulations limiting PFAS6 concentrations in drinking water to 20 parts per trillion (ppt) became effective. While PFAS6 was detected in 11 of the 20 public water supply systems, 10 of these systems met the new PFAS6 standard. The exception was Yarmouth where PFAS6 exceeded the state limit, resulting in a grade of “Poor” for that system. The widespread detection of PFAS6 in public water supplies calls for ongoing monitoring as well as planning and implementation of effective treatment methods.

Other water quality issues of concern

• Consumer tap water quality was not evaluated and would require testing of the water coming out of consumers’ taps as well as monitoring data from water distribution systems. Water quality coming out of the tap will be affected by the age and type of pipes in the distribution system and in consumers’ homes and businesses.
• Private wells were not addressed in this project. APCC strongly recommends that private well owners have their water tested and, if needed, treated.
• Drinking water consumers and regulators alike need to consider that there may be other unregulated contaminants affecting drinking water quality. These include:

• • Emerging contaminants in surface water and/or groundwater:

• • • Endocrine-disrupting compounds and pharmaceuticals from inadequately treated wastewater;
    • Microplastics from wastewater, stormwater runoff and atmospheric fallout;
    • Cyanobacteria (aka blue-green algae) in freshwater ponds produce toxins that are harmful to humans and animals if ingested. Public surface water supplies can become contaminated by cyanotoxins, and public water suppliers elsewhere are taking precautions to guard against cyanotoxins in drinking water. This issue is of limited scope on Cape Cod, as only Falmouth utilizes a surface water source for a portion of its public drinking water. APCC has been monitoring cyanobacteria since 2018 and has incorporated cyanobacteria into our pond grading system since 2019.

• Harmful bacteria in coastal waters and freshwater ponds, lakes and streams include fecal coliform bacteria and enteric bacteria that are indicators of human and/or wildlife fecal matter. Bacteria can impact swimming beach water quality and water quality in shellfish beds. Beach water quality and shellfish bed water quality are monitored by Barnstable County and the state, respectively.

• Mercury contamination of surface water continues to be of concern, based on the fact that this year 32 ponds and lakes on the Cape have fish consumption advisories due to high levels of mercury. Last year there were 29 ponds with fish consumption advisories, and the year before 24 ponds. Towns with ponds with fish consumption advisories this year included Barnstable, Bourne, Brewster, Falmouth, Mashpee, Sandwich, Truro, and Wellfleet. Mercury originates from atmospheric fallout of mercury emissions from coal-burning power plants. For more information, visit MA Fish Consumption Advisories
• Six ponds also had fish consumption advisories due to PFAS. Towns with such ponds included Bourne, Falmouth, and Mashpee.
• Climate change impacts for the Northeast are predicted to include warmer air and water temperatures year-round; more precipitation; more intense storms; longer and warmer growing seasons coupled with shorter and warmer winters; shifts in populations of fish, wildlife and invertebrates; rising sea level; changes in groundwater elevations; more flooding; and changes in dynamic landforms such as those found on the Cape (e.g., dunes, beaches, floodplains). Many of these climate change predictions will impact water quality and exacerbate the harmful effects of existing pollutants.

Filling the gaps: recommendations for monitoring

Monitoring is crucially important to understand current conditions and for tracking progress in improving and protecting water quality. Based on our findings, APCC provides the following recommendations for monitoring:

• Coastal embayments need ongoing monitoring to collect up-to-date information on water quality in order to assess whether wastewater management measures and protection measures are working and to determine when success has been achieved.
• Monitoring of five more coastal embayments is needed: Chase Garden Creek in Yarmouth, Red River in Chatham and Harwich, Hatches Harbor in Provincetown, Great Sippewissett Marsh in Falmouth, and Salt Pond in Falmouth. These embayments are listed in the 208 Water Quality Plan as coastal embayments receiving nutrients from their watersheds.
• Pond monitoring should be expanded to many more ponds and lakes throughout the Cape, particularly those where there are swimming beaches, public access, and/or sensitive resources (e.g., diadromous fish, rare species, wildlife). In 2022, the Cape Cod Commission received funding for a 208-scale study of ponds across the region called the Cape Cod Freshwater Initiative. The initiative will enable the Cape Cod Commission and its partners to undertake a comprehensive assessment of the quality of the Cape’s freshwater resources in order to establish a regional plan for restoring and protecting the Cape’s ponds and lakes.

• Cyanobacteria monitoring of ponds should be expanded as it provides a useful measure of eutrophication and a complement to water quality monitoring.
• The PALS program is useful as a “screening tool” to identify ponds where more in-depth monitoring and assessment is needed to determine causes, extent, and severity of problems. However, pond monitoring should be conducted more frequently than the once-a-year snapshot that is typically provided by the PALS program.
• Newer, more recent pond data should be utilized to assess pond conditions and inform restoration and protection efforts.
• Monitoring of pond water quality and cyanobacteria blooms should be conducted hand-in-hand so that water quality data can be used to help predict where serious cyanobacteria blooms may occur, and vice versa.
• Public water suppliers should expand their monitoring of PFAS, emerging contaminants and cyanobacteria to help safeguard public health.

SUCCESS STORIES

Despite the challenges and the need for much greater action in every town, there have been some successes in addressing nutrient pollution. These successes include the following:

• Passage of state legislation in 2018 that established the Cape Cod and Islands Water Protection Fund to provide a non-property tax-based source of funds to help Cape Cod and the Islands pay for necessary wastewater infrastructure and water quality remediation efforts. Through 2022, this fund has provided $98 million to eight towns to assist them with wastewater management and to provide dollar for dollar property tax relief to residents of Barnstable County.
• Barnstable County’s alternative septic system testing center has been testing efficacy of different alternative septic systems and has identified several as being potentially useful;
• Sewer expansion projects in Chatham and in Falmouth;
• Alternative wastewater treatment methods are being tested or utilized in towns, including permeable reactive barriers in Falmouth and Orleans and shellfish aquaculture projects in Falmouth, Barnstable, Mashpee, Yarmouth, Dennis, Orleans and Wellfleet;
• Partnering agreements between towns to share public wastewater treatment facilities (e.g., Harwich and Chatham), including first-ever sewers installed in Harwich;
• Groundbreaking in 2020 for the Orleans wastewater treatment facility and collection system, with sewer construction in downtown Orleans continuing throughout 2022;
• The state’s first Watershed Permit for four towns in the Pleasant Bay watershed, designed to facilitate a coordinated effort by the towns of Brewster, Chatham, Harwich and Orleans and the Pleasant Bay Alliance to control nutrient pollution in Pleasant Bay (see Pleasant Bay Watershed Permit);
• Intermunicipal agreement between Mashpee, Sandwich and Barnstable for nitrogen load sharing for the cleanup of Popponesset Bay;
• Pond restoration success stories have been compiled by the Cape Cod Commission. Success stories for freshwater ponds are fewer because ponds have not received the attention that coastal embayments have received; and
• Additional water quality improvement success stories can be found on the Cape Cod Commission’s website.

Finally, ecological restoration projects provide benefits for water quality as well as ecological benefits for fish and wildlife habitat. Several restoration projects that are planned, underway or completed include: Parkers River tidal restoration, Herring River tidal restoration, Childs River freshwater wetland restoration, Coonamessett River restoration, Sesuit Creek salt marsh restoration, Three Bays stormwater remediation project, Stony Brook salt marsh and fish passage restoration, and others. APCC’s Restoration Coordination Center is assisting with many of these projects and provides Cape Cod communities with assistance in planning and implementing successful restoration projects. For more information on restoration projects on Cape Cod, visit APCC’s website.

Maps

Click on a map image below to open the corresponding PDF.