Status and Trends: Water Quality in the Southern Rhode Island Coastal Lagoons, Salt Ponds 2008 - 2012 Coalition
Prepared by Elise Torello Edward Callender, PhD Salt Ponds Coalition December, 2013
www.SaltPondsCoalition.org Status and Trends: Water Quality in the Southern Rhode Island Coastal Lagoons, 2008 - 2012
Prepared by Elise Torello Executive Director, Salt Ponds Coalition
Edward Callender, PhD Vice President, Salt Ponds Coalition December, 2013
Salt Ponds Coalition Board of Directors Arthur Ganz, President Edward Callender, PhD, Vice President Marshall Mugge, PhD, Treasurer David Bailey, Secretary John Crandall, Sarah Dodd, Barbara Engel, Sharon Frost, Martha Hosp, William Lester, Leo Mainelli, Chris Randall, Richard Sartor, Ted See
www.SaltPondsCoalition.org
Salt Ponds Coalition’s Mission: To protect and enhance the health of the salt ponds for the benefit of wildlife and people.
Salt Ponds Status and Trends 2008 - 2012 Page 2 Message from the Contents Salt Ponds Coalition 4 Introduction President 4 Water Quality Monitoring Back in the late 1970s while working on the de- Sampling Methods velopment of the Salt Ponds Special Area Manage- ment Plan we learned that the most important in- gredient needed to operate and evaluate changes 6 What SPC Monitors and Why in the habitat was monitoring. Experience showed that the state wasn’t going to fund it, and grant money had limitations. Our research group from 7 The Aquatic Health Index the University of Rhode Island, Coastal Resources Management Council, and Department of Environ- 8 Bacteria mental Management was successful in organizing volunteers called the Pondwatchers. Little did I know then how important it was to train dedicated 9 Submerged Aquatic citizens to perform this important function. Lab Vegetation analysis was initially done at URI, later by the U.S. Public Health Service and eventually by URI Watershed Watch. Today, our testing results are 10 Winnapaug Pond shared and have become the baseline for much University and government regulatory research. 12 Quonochontaug Pond This document will present an analysis of the results of five years of testing. Changes in the 14 Ninigret Pond overall water quality are documented. Nutrient enrichment, eutrophication, and bacterial con- tamination are our major threats to healthy pond 16 Green Hill Pond ecosystems. 18 Potter Pond Analysis presented here could not be possible without the knowledge of Dr. Ted Callender, tech- nological skills of Elise Torello, the analytical sup- 20 Point Judith Pond port of URI Watershed Watch, and the countless hours of over 60 Ponds Watchers who have served 26 Bacteria Data in the last 28 years.
Art Ganz, President 30 Pond Stewardship: What We All Can Do to Help Improve Water Quality
SPC is most appreciative of Rhode Island Rivers Council and the Rhode Island Water Resources Board for their ongoing support of our water quality monitoring program.
Page 2 Page 3 Salt Ponds Status and Trends 2008 - 2012 Introduction Salt Ponds Coalition (SPC) has which cost $600 per sampling site per following spring, after all data are ana- been monitoring water quality in the year in laboratory fees. lyzed, processed, and quality assured. southern Rhode Island coastal lagoons, Financial support for water quality At SPC we are often asked, are the also known locally as salt ponds, for monitoring from the State of Rhode ponds getting cleaner or dirtier? This is almost 30 years! SPC is proud to be Island has been more limited every a difficult question to answer. With so the oldest volunteer marine water qual- year. Therefore, Salt Ponds Coalition many natural and man-made processes ity monitoring program in the nation. (SPC) is the only organization collect- in and around the ponds, water quality First and foremost, we sincerely thank ing water quality data in the salt ponds is in a constant state of flux. Within our many dedicated pond watchers— every year, year after year. Having a each pond, depending on how close a without their ongoing efforts every two long-term dataset is critical to moni- site is to a breachway to the ocean, a weeks from May through mid-Octo- toring water quality trends in the ponds freshwater tributary or spring, or a fail- ber, we would not have this important and spotting potential problems that ing septic system, water quality can vary long-term and thorough data record on may be brewing. So far, SPC has over widely. However, this report will par- our salt ponds. We also offer our deep 50,000 data points, and we are adding tially answer the question of whether gratitude to our generous members more each and every year. Data col- conditions are improving or declining, who support our water quality testing lected during the current sampling sea- at least concerning nutrient, bacteria, program by sponsoring sampling sites, son will be added to our database the and algae concentrations.
Water Quality Monitoring Sampling Methods
Planning for a water quality moni- as have several neighborhood groups, toring season begins in late winter fire districts, and individual donors. We each year, when SPC’s Environment are very grateful for their generosity. Committee meets to assess the previ- The sampling season officially be- ous season and determine whether any gins in the middle of April when we modifications are necessary for the hold the yearly training (or refresher) next season. At that time, it is decided program for our monitors. The volun- whether the number and locations of teers learn how to collect samples cor- sampling sites are adequate for deter- rectly and consistently, how to process mining water quality, and whether the the samples and, in the case of dis- funding and volunteers are available to solved oxygen (DO), perform the actual monitor all proposed sites. If necessary, analysis and record the findings. Most plans are made to recruit more volun- volunteers have little to no background teers and secure additional funding for in science, and some are initially a bit monitoring sites. The Rhode Island intimidated by the chemistry involved. Rivers Council has been an ongoing SPC’s trainers reassure our new recruits supporter of our monitoring program, that if you’ve ever followed a recipe in your kitchen, you can certainly perform ing daylight as aquatic vegetation and a DO titration. It is definitely easier algae photosynthesize, which produces than putting together a bookshelf from oxygen. At night, photosynthesis is not Ikea! Samplers also are reassured that occurring and decomposition of dead if they have any questions or encounter plants and algae consumes oxygen. any problems, they have support and Determining the lowest DO of the day backup from the trainers and veteran is important, as a very low (hypoxic) or samplers, some of whom have been no (anoxic) oxygen event can be fatal to sampling for over 10 years! marine organisms. Our volunteer monitors collect There are two types of sampling samples early in the morning (before days during the season—water collec- 8:30 AM) to attempt to capture the tion days and monitoring days. There lowest DO concentrations of the day. are six water collection days per year Spring training session for volunteers. These concentrations tend to rise dur- (one per month, May through Octo- Salt Ponds Status and Trends 2008 - 2012 Page 4 ber), plus six or seven monitoring days. samples from the coolers, then drives These types of sampling days alternate them all to the URI WW lab. Labora- every two (or occasionally three) weeks. tory staff sign in the samples and later On a monitoring day, volunteers perform the analyses. gather their data collection cards and At URI WW, all data, including sampling gear and head out to their field observations recorded by the mon- sampling site(s) by foot (collecting itors on the data cards, are entered into from a dock), kayak, or boat. Every- Excel spreadsheets and undergo several one collects shallow (arm’s length) wa- rounds of quality assurance. Once URI Water monitoring “tools of the trade.” ter samples for DO and chlorophyll-a sends the spreadsheets to SPC, they un- analysis, plus a temperature measure- Winkler titration kits, which give a re- dergo even more quality assurance and ment. The time of day and weather/ sult in milligrams of oxygen per liter of are imported into a Microsoft Access tide conditions are also noted on the water (mg/L). Later, for the purposes database. SPC has developed database data card. At deep sites, where water of assessing aquatic health, these mg/L reporting software to automatically conditions are possibly quite different measurements will be converted to per- produce a one page report with a table at the top and bottom of the water col- cent saturation using the water tem- and a bar chart showing all data for a umn, temperature is measured and DO perature measurement noted during particular sampling parameter (dis- samples are also collected one meter sample collection (% saturation equals solved oxygen, nitrate, ammonia, etc.) above the bottom using special sam- the concentration of DO in the sam- for a particular site (surface and deep pling apparatus. At these sites, water ple divided by the maximum possible for some sites) for every year the site clarity is also measured using a “Secchi concentration of DO in water of that was monitored. Thus far, there are over disk.” A Secchi disk is a weighted circle salinity and temperature, times 100). 1,600 of these files available online, all of wood divided into white and black The water samples collected for deter- accessible through a clickable Google quarters, suspended on a line with mining chlorophyll-a concentration (a Map. Each marker on the maps rep- markings for meters and centimeters of measure of how much phytoplankton, resents a sampling location; clicking on depth. This disk is lowered through the or microscopic algae, are in the water) a marker displays links to the data re- water until an observer using a special are processed by the volunteer by pass- ports for that location. ing (2) 50 milliliter aliquots of each Salt Ponds Coalition is proud to sample through separate fiberglass fil- make our data available for use by pol- ters. These filters are then frozen in icy-makers, scientists, students, and of Ziploc baggies containing desiccant course, the public. With the continued for later transport to the University of support of our members, we look for- Rhode Island Watershed Watch (URI ward to continuing to build this valu- WW) laboratory. able resource for everyone interested in On water collection days, all of the the health of the ponds. activities of monitoring days are per- A Secchi disk. Photo: greatlakesecho.org formed, plus additional water samples for determining nutrient (nitrate, am- viewing tube can no longer see it from monium, total nitrogen, total phos- the surface, at which point the depth phorus, and dissolved phosphorus) of the disk below the water’s surface is and bacteria (fecal coliform and en- noted by looking at the marking on the terococci) concentrations are also col- line from which the disk is suspended. lected. These samples are collected at All water samples are kept on ice in arm’s length; at deep sites, an additional coolers and transported to shore. On nutrient sample is collected one meter shore, the water samples are analyzed above the bottom. The volunteers leave for oxygen concentration and filtered their water samples and chlorophyll-a for later chlorophyll-a analysis. Some filters on ice in coolers at several “cen- samplers work in a garage or other tral” drop-off locations along the south workspace, others in their kitchen— coast of RI. The SPC monitoring co- nothing hazardous is involved. DO ordinator then traverses the state from analysis is performed using standard Westerly to Wakefield collecting the Page 4 Page 5 Salt Ponds Status and Trends 2008 - 2012 SPC’s Water Quality Monitoring Program: WHAT we measure, WHY we measure it, and THRESHOLDS for GOOD vs. POOR scores for components of the Aquatic Health Index (AHI). AHI scores can be in the range of 0 to 100; scores less than 35 are POOR, and scores greater than 65 are GOOD. Bacteria are not part of the AHI, but are also sampled by SPC. See pages 30 - 31 to see what actions can be taken to improve ALL of these parameters.
WHAT We THRESHOLDS for GOOD and WHY We Measure It Measure POOR AHI Scores Dissolved Dissolved oxygen (DO) is critical to marine life. Low-oxygen Oxygen (DO), conditions cause stress to marine organisms, and no-oxygen Temperature conditions can be fatal. DO concentrations fluctuate throughout the HIGHER Dissolved Oxygen day, and tend to be lowest early in the morning, particularly in Saturation is GOOD
deeper water. Warmer water can hold less DO; therefore, we need GOOD: > 72.5 % saturation to know the water temperature in order to calculate how close the POOR: < 57.5 % saturation measured DO concentration was to the maximum DO amount that the water could hold at that temperature (% saturation).
Water Clarity Reduced water clarity is harmful to submerged aquatic vegetation HIGHER Secchi Depth such as eelgrass, the dominant submerged aquatic vegetation is GOOD species in the southern RI salt ponds. A Secchi Disk is used to measure water clarity at SPC’s deeper sampling locations, where the GOOD: > 2.2 meters pond bottom is usually not visible from the surface of the water. POOR: < 1.4 meters Chlorophyll-a Elevated nutrient levels, especially nitrogen, can stimulate excessive LOWER Chl-a Concentration algae growth, which in turn lowers water clarity and dissolved (micrograms per liter, ug/L) oxygen levels (at night when algae are not photosynthesizing, and is GOOD also as bacteria decompose dead algae, a process which consumes oxygen). Measuring chlorophyll-a (Chl-a) concentration gives an GOOD: < 5.5 ug/L indication of how much microscopic algae is in the water. POOR: > 7.6 ug/L Dissolved Excess nitrogen in the ponds is detrimental to water quality and LOWER DIN Concentration Inorganic marine life. Algae and plant growth in estuarine and marine systems (micrograms per liter, ug/L) Nitrogen (DIN) are mainly fueled by Dissolved Inorganic Nitrogen (DIN), which is is GOOD made up of nitrate-nitrogen plus ammonium-nitrogen. Excessive algae growth due to elevated DIN lowers water quality and dissolved GOOD: < 58 ug/L oxygen as noted above for chlorophyll-a. POOR: > 96 ug/L
Total Organic Total Organic Nitrogen (TON) is nitrogen that is part of organic LOWER TON Concentration Nitrogen (TON) compounds; that is, part of living or dead organisms. TON is (micrograms per liter, ug/L) determined by subtracting DIN from total nitrogen data, which is GOOD includes dissolved and particulate inorganic and organic nitrogen forms. TON contributes dissolved inorganic nitrogen back to the GOOD: < 393 ug/L water as dead organisms decompose. POOR: > 489 ug/L Bacteria Elevated bacteria levels can indicate the presence of human sewage RIDEM saltwater primary (Fecal coliform, and pathogens (disease-causing organisms), and result in beach contact recreational criteria, enterococci) closures (due to enterococci levels) and closure of shellfish beds Most Probable Number/100 milliliters (due to fecal coliform levels). Potentially harmful bacteria and Enterococci single sample: pathogens can end up in the marine environment from a variety of 104 MPN/100 mL sources, both natural (wildlife) and anthropogenic (septic systems, Fecal coliform: not more stormwater, pets/livestock, etc.). Heavy rainfall events can than 10% of total samples exacerbate the problem and result in additional closures. > 400 MPN/100 ml
Salt Ponds Status and Trends 2008 - 2012 Page 6 The Aquatic Health Index (AHI) Our very large water quality data- total organic nitrogen (TON), and Sec- reliable ammonium data back to 2008. base includes parameters such as dis- chi depth (at deep sites only). Dissolved Therefore, we have only produced AHI solved oxygen (DO, mg/L), bacteria oxygen is critical to the health of aquat- reports for data going back to that year. (MPN/100mL), chlorophyll-a (ug/L), ic organisms. Excess nitrogen in the We have additional valuable data go- nitrate (ug/L), and ammonium (ug/ form of nitrate and ammonium, which ing back as far as 1985 for some sites, L)—important data which may not together make up DIN, fuels excess but not all of the parameters we would make much sense to non-scientists. algae growth. Abundant algae in the need to calculate AHI scores. For some of these data, high numbers water, indicated by high chlorophyll-a To look at possible improving or are good (DO, for example—more is levels, decreases water clarity and con- declining trends in water quality, the better). For others, high numbers are sumes DO as it decomposes. TON overall AHI scores for each site, and of concern (e.g., bacteria and nutrients). is the nitrogen that is part of organic the AHI scores for each parameter, How do we turn all of these data into compounds, that is, locked up in living were plotted versus time in Micro- information that people can use? This organisms. TON contributes inorganic soft Excel. Using MS Excel’s built-in is an ongoing question with which all nitrogen to the water when living or- functionality, a trendline was computed watershed organizations struggle. ganisms die and decompose. Secchi for each set of AHI scores. From the At SPC, we are fortunate to have depth is included for deeper sites, but equation for each trendline, the slope of a PhD geochemist (with expertise in most of the SPC sampling sites are too the line was used to indicate whether geology and water chemistry) on our shallow for Secchi measurements (the an improving or declining trend was board of directors--Dr. Ted Callen- disk would be visible on the bottom). indicated. We defined a “moderate” der. Dr. Callender adapted an Aquatic An average AHI score is calculated improvement or decline as a trendline Health Index (AHI) developed for for each testing site. At deep sites, the with a slope (m) of greater than 2 (im- Buzzard’s Bay, MA (buzzardsbay.org/ average of the AHI scores for shallow provement of more than 2 AHI points eutroindex.htm) for use with our RI and deep data for each parameter were per year) or less than -2 (decline of salt ponds. This AHI uses equations used to calculate the overall site aver- more than 2 AHI points per year). A based on scientific research about age. SPC produces a yearly report for “strong” improvement or decline was healthy thresholds for five of our test- each pond including a table of AHI defined as a trendline with a slope in ing parameters to score data on a scale values and a map showing symbols for the steepest 75% of slopes for the AHI of 0 to 100, just like a school report the AHI scores for each parameter at scores—thus, defined as a strong trend card (Table 1). Thus, a score of less than each site: blue star = good, green up relative to the data collected at our 35 for a data value is poor and a score triangle = Fair+, yellow down triangle monitoring sites. Using these criteria, of greater than 65 is good, regardless of = Fair-, and red hexagon = poor. All of a strong improvement was defined as a whether an actual low or high data value these reports are available through our trendline with a slope greater than 8.6, is “bad” or “good.” For example, a high web site: www.saltpondscoalition.org/ while a strong decline was defined as a AHI score would be calculated for a monitoring.html. trendline with a slope of less than -8.6. high DO data value (high DO=good!), The AHI maps available for view- “No trend” was defined as a trendline and a high AHI score is also calculated ing on our web site present a snapshot with a slope greater than or equal to for a low dissolved inorganic nitrogen of the water quality status of the ponds -2 and less than or equal to 2, with a (DIN) data value (low DIN=good!). each summer going back through 2008. range of AHI scores over the five years The parameters used in calculating Ammonium is an important factor in (maximum minus minimum) of <= 15. the AHI are DO, chlorophyll-a, DIN, computing the AHI, and SPC only has A range within 15 AHI points was Table 1. AHI linear equations, values for scores of 0 and 100 for each parameter, and score categories. chosen because this is 0 value 100 value the number of points (solving x (solving x AHI representing one AHI AHI Equations Solving for x for y=0) for y=100) Units Guidelines category (Poor to Fair-, Fair- to Fair+, DO y = 2x - 80 x = (y + 80)/2 40.0 90.0 % Sat. Good, >65 and Fair+ to Good). Secchi y = 41.635x - 24.98 x = (y + 24.98)/41.635 0.6 3.0 meters Fair +, 50-65 To represent these Chl-a y = -14.286x + 142.86 x = (y - 142.86)/-14.286 10.0 3.0 ug/L Fair -, 35-50 trends on an AHI DIN y = -795.33x + 111.17 x = (y - 111.17)/-795.33 140 14 ug/L Poor, <35 map, we added anoth- TON y = -313.14x + 188.07 x = (y - 188.07)/-313.14 601 281 ug/L er symbol next to each AHI symbol for each
Salt Ponds Status and Trends 2008 - 2012 Page 6 Page 7 site on each 2012 map (Table 2). The between the AHI and time. It repre- line symbolically by using the color of added symbol is an arrow, indicating sents how well the trendline represents the trend arrow to express the strength a trend, or a circle, indicating that the the data, and how confident one can of the fit of the trendline to the data. data were too variable to see a trend. be in making predictions based on the An r2 >= 0.75 was considered a “strong” The direction that the arrow points in- plot of data. Coefficient of Determi- fit; 0.5 <= r2 < 0.75 was considered a dicates the trend in water quality from nation (r2) values are always within the “moderate” fit; 0.25 <= r2 < 0.5 was con- 2008 - 2012: straight up (12:00 noon) range of 0 to 1. An r2=1 indicates that sidered a “weak” fit; and r2 < 0.25 was = strong improvement, 2:00 = moderate all of the data values fall exactly on the considered too variable to identify a improvement, sideways (9:00 <-> 3:00) trendline and are highly predictable; trend (very weak linear relationship). = no improvement or decline, 4:00 = an r2=0 indicates no linear relationship So, an improving trend with a strong moderate decline, and straight down between time and the AHI. An r2 of fit is dark blue, an improvement with (6:00) = strong decline. 0.75, for example, indicates that 75% of a moderate fit is medium blue, and an The r2, or Coefficient of Deter- the total variation in AHI scores can be improvement with a weak fit is light mination, was also computed for each explained by the linear relationship be- blue; a sideways arrow (no trend) is trendline in MS Excel. The 2r indicates tween time and AHI. yellow; a yellow circle indicates that 2 the strength of the linear association We represent the r for each trend- the data were too variable to indicate Table 2. Symbols indicating AHI trends (m = slope of trendline) and strength of fit a trend; a declining trend (r2 value of trendline) on water quality maps. with a strong fit is dark Flat (Arrow, red, a decline with a mod- Strong Improving Improving -2.0 <= m <= 2.0) Declining Strong Declining erate fit is medium red, (8.6 < m) (2.0 < m <= 8.6) or Too Variable (-8.6 <= m < -2.0) (m < -8.6) (Circle, r2 < 0.25) and a decline with a weak Strong Fit trend is light red (Table 2). 2 (0.75 <= r ) As more years of data are Moderate Fit added, we expect any trends 2 (0.5 <= r < 0.75) in water quality to become Weak Fit 2 more apparent.
(0.25 <= r < 0.5)
Bacteria Failing septic systems, storm drains, uses enterococci bacteria as an indica- ing data are not used for official public non-point storm water runoff, abun- tor of the presence of fecal mater, and health purposes; rather, they are in- dant waterfowl, pets, farm animals, and associated increased risk of contracting tended to be used to find trouble spots wildlife all contribute bacteria to the gastrointestinal illnesses from water and track improvements or declines in salt ponds. Densely populated sea- contact. Therefore, the RI Department bacteria levels over time. The RI DEM sonal communities and warm summer of Health adopted single-value entero- saltwater enterococci primary contact weather can exacerbate bacterial issues cocci standards for licensed swimming recreational/swimming single sample in the ponds. Bacteria levels are also beaches in 2004, and the Rhode Island criterion is 104 MPN (most probable affected by rainfall events, which can Department of Environmental Man- number of bacteria) per 100 millili- cause spikes in bacteria concentrations agement (RI DEM) adopted entero- ters (ml) of water. This is the criterion and result in closure of beaches and cocci for contact recreation standards used for determining beach swimming provisional shellfishing grounds. on all waters (fresh and salt) shortly advisories as evaluated by the RI De- When people learn that Green after (Addy et al, 2010). In addition, as A failed septic system. Hill and eastern Ninigret Ponds are required under the National Shellfish Photo: www.521flow.com closed to shellfishing, they sometimes Sanitation Program for shellfish wa- ask if it is safe to be in contact with the ters and as an indicator of overall water water. One way to determine that is quality, RI DEM continues to assess to test the water for bacteria that in- fecal coliform bacteria levels. dicate the presence of human sewage The water samples collected by SPC and associated pathogens (organisms for bacterial analysis are tested at URI that cause disease). The US Environ- Watershed Watch for both enterococci mental Protection Agency (US EPA) and fecal coliform bacteria. The result- Salt Ponds Status and Trends 2008 - 2012 Page 8 partment of Health (RI DEM Water bacteria, the RI DEM saltwater pri- shall exceed 400 MPN/100 ml, applied Quality Regulations, sos.ri.gov/docu- mary contact recreational/swimming only when adequate enterococci data ments/archives/regdocs/released/pdf/ single sample criterion is that not more are not available. DEM/6224.pdf ). For fecal coliform than 10% of the total samples taken
Submerged Aquatic Vegetation
Submerged aquatic vegetation eelgrass beds. Table 3. Submerged Aquatic Vegetation acreage in the southern (SAV) meadows are extremely impor- Due to the RI coastal ponds, 2009 and 2012 (Data Source: RIGIS). tant habitats in shallow coastal loca- importance of 2009 2012 Change Pond Change (%) tions. These habitats provide numerous eelgrass meadow Acres Acres (Acres) valuable ecosystem services, including: habitat, eelgrass Winnapaug* 0 0 0 0.0 water purification through nutrient is protected at Quonochontaug 93 71 -22 -23.7 uptake and trapping of particulates; both the federal Ninigret** 203 193 -10 -4.9 coastal protection through wave at- and state level. tenuation/dissipation; erosion control Several SAV Green Hill 138 91 -47 -34.1 through sediment stabilization; sup- mapping projects Potter 75 67 -8 -10.7 port of economically important fisher- have been con- Point Judith 94 101 7 7.4 ies through providing reproductive and ducted in Rhode * Winnapaug’s lack of SAV was not ground-truthed in either year. nursery grounds, plus shelter for young Island to docu- **Ninigret’s SAV beds were not ground-truthed in 2009. animals; carbon sequestration (sig- ment the extent nificant carbon used by the plants for of SAV beds and track changes (trends) Ponds lost almost 24% and almost 11%, growth is buried in the sediment when in their distribution. A RI Eelgrass respectively. Winnapaug Pond had no the plants die); and habitat for other Task Force was formed to continue this SAV beds identified in either year. diverse wildlife species (wading birds, effort long-term (Bradley et al, 2013). The authors of the 2013 SAV re- etc.) (Barbier et al, 2011). Analysts at the University of Rhode port caution that only two survey years The most common SAV species in Island Environmental Data Center are not enough to determine a trend, the southern RI salt ponds is eelgrass (URI EDC) manually interpreted or- and the team could not ground-truth (Zostera marina). The other species thophotography (aerial photography) all SAV beds identified in their digital present in a few lower-salinity (com- of the shallow coastal waters of RI to delineations. The authors recommend pared to full seawater) locations is wid- produce preliminary delineations of that SAV mapping be performed every geon grass (Ruppia maritima). Eelgrass SAV beds using Geographic Informa- three years to better enable the deter- is very sensitive to elevated nutrient tion Systems (GIS) software (Bradley mination of long-term trends. levels in coastal waters. Elevated nu- et al, 2013). The analysts also identi- ~~~~~~~~~~~~~~~~~~~~~~ trient concentrations cause increased fied areas to be ground-truthed by team algae growth, which in turn decreases members in the field. References water clarity. Excess algae growth on The final SAV bed delineations are Addy, K., E. Herron, and L. Green. 2010. eelgrass leaves (epiphytes), along with stored and available digitally as GIS da- Bacterial Monitoring. URI Watershed less light penetration through the wa- tasets (shapefiles) from the URI EDC’s Watch. www.uri.edu/ce/wq/ww/Publica- ter column due to abundant microalgae RIGIS data portal. For the southern tions/Bacteria.pdf. (phytoplankton), are detrimental to RI coastal ponds, SAV bed delineations Barbier, E.B., S.D. Hacker, C. Kennedy, Eelgrass (Zostera marina). are available for 2009 and 2012 and are E.W. Koch, A.C. Stier, and B.R. Silliman. Photo: coz.southernfriedscience.com shown on the pond maps in this Status 2011. The value of estuarine and coastal and Trends report. GIS software was ecosystem services. Ecological Mono- used to calculate the sizes of the SAV graphs, 81:2, pp. 169-193. beds, which allowed determinination of Bradley, M., R. Hudson, M.C. Ekberg, K. changes in their aerial extent (Table 3). Raposa, and A. MacLachlan. 2013. 2012 All of the ponds except for Point Judith Mapping Submerged Aquatic Vegetation had declines in the extent of their SAV (SAV) in Rhode Island Coastal Waters. beds. Ninigret Pond lost about 5% of University of Rhode Island, Save the Bay, its SAV area, Green Hill Pond lost over National Estuarine Research Reserve, and 34%, and Quonochontaug and Potter U.S. Fish and Wildlife Service. Page 8 Page 9 Salt Ponds Status and Trends 2008 - 2012 Aquatic Health of Winnapaug Pond: 2012 Status and 2008 - 2012 Trends 2012 AHI Score and 5-year Trend
^_ Good
*# Fair + * # DO: Fair - Chl-a: DIN: %2 Poor TON: Eelgrass 2009 (PROBABLY none--unconfirmed) Eelgrass 2012 (PROBABLY none--unconfirmed)
DO: ^_ Chl-a: East DIN: TON: Basin
SW*# Corner / Miles 0 0.1 0.2 0.4 0.6
RIGIS, URI EDC, RIDEM
Winnapaug Pond: Overall SPC currently monitors two sites in 100 Winnapaug Pond. At both sites, 2012 wa- 90 ter quality for individual parameters and 80 Southwest Corner overall was either in the Fair+ or Good 70 AHI category. In addition, all trends indi- 60 cated by the data were moderate or strong 50 East Basin improvements. At the Southwest Corner 40
Score AHI site, DIN and TON data were too variable 30 Linear (SW Corner, to determine a trend, but DO and chlo- 20 r2=0.57) rophyll AHI scores were both strongly 10 Linear (E. Basin, improving; that is, summer DO concen- 0 r2=0.45) trations are increasing and the 6-month 2008 2009 2010 2011 2012 chlorophyll concentrations are decreasing.
Salt Ponds Status and Trends 2008 - 2012 Page 10
Aquatic Health of Winnapaug Pond: 2012 Status and 2008 - 2012 Trends Winnapaug Pond: Dissolved Oxygen 100 2012 AHI Score and 5-year Trend 90 80 Southwest Corner ^_ Good 70
60 East Basin
*# Fair + 50 * # DO: Fair - Chl-a: 40 Linear (SW Corner,
Score AHI r2=0.43) DIN: 30 %2 Poor TON: 20 Linear (E. Basin, r2=0.30) Eelgrass 2009 (PROBABLY none--unconfirmed) 10 0 Eelgrass 2012 (PROBABLY none--unconfirmed) 2008 2009 2010 2011 2012
Winnapaug Pond: Chlorophyll-a 100 90
80 Southwest Corner DO: ^_ 70 Chl-a: 60 East East Basin DIN: 50 TON: Basin 40 Score AHI 30 Linear (SW Corner, r2=0.79) 20 10 Linear (East Basin, 0 r2=0.32) SW*# 2008 2009 2010 2011 2012 Corner Winnapaug Pond: Dissolved Inorganic Nitrogen 100 90 80 Southwest Corner 70 60 East Basin 50 Linear (SW Corner, 40 Score AHI r2=0.09) 30 / Linear (East Basin, Miles 20 r2=0.58) 0 0.1 0.2 0.4 0.6 10 RIGIS, URI EDC, RIDEM 0 2008 2009 2010 2011 2012 For the East Basin site, summer DO con- Winnapaug Pond: Total Organic Nitrogen centrations are increasing somewhat but 100 chlorophyll concentrations have no trend. 90 The DIN AHI scores exhibited a strong 80 increasing trend, suggesting that the con- 70 Southwest Corner centrations of ammonium and nitrate are 60 East Basin decreasing with time. The moderate im- 50 40 proving trend for TON AHI scores sug- Score AHI Linear (SW Corner, gests that TON concentrations are also 30 r2=0.09) decreasing over time. 20 Linear (E. Basin, Thus, the water quality data indicate 10 r2=0.75) good news for Winnapaug Pond. Unfortu- 0 2008 2009 2010 2011 2012 Continued on page 22. Page 10 Page 11 Salt Ponds Status and Trends 2008 - 2012 Aquatic Health of Quonochontaug Pond: 2012 Status and 2008 - 2012 Trends 2012 AHI Score and 5-year Trend DO: DO: ^_ Good Secchi: Secchi:
Chl-a:
*# Fair + Chl-a:
* DIN: # DIN:
Fair - TON: TON:
* %2 East Basin ^_ N# inigret Crawford Dock Poor Yacht Club Eelgrass 2009 Eelgrass 2012
North ^_ Bill's Island DO: Chl-a: DIN: TON: *# DO: Harmonic Chl-a: Cove Buoy DIN: TON: *# ^_ Harmonic Judge's Cove Channel Rock
DO: Secchi: Chl-a: / DIN: Miles TON: 0 0.125 0.25 0.5 0.75 1
RIGIS, URI EDC, RIDEM
Quonochontaug Pond: Overall East Basin Yacht Quonochontaug Pond is one of Club 100 Harmonic Cove our larger and deeper salt ponds, and 90 Buoy Harmonic Cove has a permanent breachway to the 80 Channel ocean. Because of its complex coast- 70 Judge’s Rock line with several coves and sub-basins, 60 North of Bill’s SPC currently monitors five sites in 50 Island Linear (E. Basin Quonochontaug Pond. All of the sites 40 YC, r2=0.02) Score AHI have either Good or Fair+ overall AHI 30 Linear (H. Cove Buoy, r2=0.74) scores, but three sites (Harmonic Cove 20 Linear (H. Cove Chan., r2=0.82) Buoy, Harmonic Cove Channel, and 10 Linear (Judge's North Bill’s Island) show moderately 0 Rock, r2=0.22) Linear (N. Bill's Is., declining trends in water quality. The 2008 2009 2010 2011 2012 r2=0.29) East Basin Yacht Club site shows no
Salt Ponds Status and Trends 2008 - 2012 Page 12 Quonochontaug Pond: Dissolved Oxygen East Basin Yacht Aquatic Health of Quonochontaug Pond: 2012 Status and 2008 - 2012 Trends Club 100 Harmonic Cove 90 Buoy 2012 AHI Score and 5-year Trend Harmonic Cove 80 DO: DO: Channel ^_ Good 70 Judge’s Rock Secchi: Secchi:
Chl-a: Chl-a: 60 North of Bill’s
*# Fair + 50 Island * DIN: # DIN: Linear (E. Basin
TON: TON: 40 YC, r2=0.34)
Fair - Linear (H. Cove 30 * # Buoy, r2=0.85) East Basin ^_ Ninig Score AHI ret Crawford Dock %2 Poor 20 Linear (H. Cove Yacht Club Chan., r2=0.49) Eelgrass 2009 10 Linear (Judge's 0 Rock, r2=0.67) Eelgrass 2012 Linear (N. Bill's 2008 2009 2010 2011 2012 Is., r2=0.03) Quonochontaug Pond: Chlorophyll-a East Basin Yacht Club North ^_ 100 Harmonic Cove 90 Buoy Bill's Island Harmonic Cove 80 Channel DO: 70 Judge’s Rock Chl-a: 60 North of Bill’s DIN: 50 Island TON: Linear (E. Basin 40 YC, r2=0.08) AHI Score AHI Linear (H. Cove 30 Buoy, r2=0.09) *# 20 Linear (H. Cove Chan., r2=0.31) 10 Linear (Judge's DO: Harmonic 0 Rock, r2=0.09) Linear (N. Bill's Chl-a: Cove Buoy 2008 2009 2010 2011 2012 DIN: Island, r2=1) TON: Quonochontaug Pond: Dissolved Inorganic N East Basin Yacht ^_ Club # 100 Harmonic Cove * 90 Buoy Harmonic Harmonic Cove Judge's Cove Channel 80 Channel Rock 70 Judge’s Rock
60 North of Bill’s DO: 50 Island Secchi: Linear (E. Basin 40 YC, r2=0.93) Chl-a: / Score AHI Linear (H. Cove 30 DIN: Buoy, r2=0.97) TON: Miles 20 Linear (H. Cove 0 0.125 0.25 0.5 0.75 1 Chan., r2=0.97) 10 Linear (Judge's RIGIS, URI EDC, RIDEM 0 Rock, r2=0.87) Linear (N. Bill's 2008 2009 2010 2011 2012 Island, r2=0.95) improvement or decline, and the over- Quonochontaug Pond: Total Organic N East Basin Yacht all AHI scores at the Judge’s Rock site Club 100 Harmonic Cove were too variable to determine a trend. 90 Buoy Harmonic Cove Dissolved oxygen (DO) AHI 80 Channel scores at the westernmost three sites 70 Judge’s Rock
were either Fair- or Poor, and declin- 60 North of Bill’s ing. In 2008 through 2010, DO AHI 50 Island Linear (E. Basin scores at all five sites were relatively 40 YC, r2=0.74) AHI Score AHI Linear (H. Cove similar but diverge widely in 2011, and 30 Buoy, r2=0.00) even more so in 2012. Chloroplyll-a 20 Linear (H. Cove Channel, r2=0.01) AHI scores for all sites were Good, 10 Linear (Judge's and there were no clear pond-wide 0 Rock, r2=0.16) Linear (N. Bill's trends. 2008 2009 2010 2011 2012 Island, r2=0.07) Continued on page 22.
Page 12 Page 13 Salt Ponds Status and Trends 2008 - 2012 Aquatic Health of Ninigret Pond: 2012 Status and 2008 - 2012 Trends 2012 AHI Score and 5-year Trend
^_ Good DO: *
Chl-a: #
*# Fair + DIN: * # DO: TON: Stumpy Fair - Chl-a: Point DIN: %2 Poor TON: %2 Eelgrass 2009 DO: Eelgrass 2012 Chl-a: DIN: %2 TON: %2 *# Vigna's Potato Dock Point
Mid West DO: Basin Chl-a: %2 DIN: TON:
Crawford's * # DO: NA Dock Chl-a: DIN: / TON: Miles 0 0.125 0.25 0.5 0.75 1 1.25 1.5
RIGIS, URI EDC, RIDEM
Ninigret Pond: Overall Crawford Dock Ninigret Pond, the largest of the 100 Potato Point southern RI salt ponds, currently has five 90 Stumpy Point monitoring sites. Two sites are located in 80 the western basin of the pond: Crawford’s Vigna's Dock 70 Dock, at the far western shore, and Mid 60 Western Basin Western Basin. The other three sites are 50 Linear (Crawford at the eastern end of the pond, closer to 40 Dock, r2=0.01) Score AHI Linear (Potato Pt., the permanent breachway to the ocean. 30 r2=0.00) The breachway had filled significantly with 20 Linear (Stumpy Pt., r2=0.05) sand from the ocean, but was dredged in 10 Linear (Vigna's the winter of 2011/2012. Dredging of the 0 Dock, r2=0.59) Linear (W. Basin, breachway will be performed every three to 2008 2009 2010 2011 2012 r2=0.24) five years to prevent sand from burying re-
Salt Ponds Status and Trends 2008 - 2012 Page 14
Aquatic Health of Ninigret Pond: 2012 Status and 2008 - 2012 Trends Ninigret Pond: Dissolved Oxygen Crawford Dock 100 Potato Point 90 2012 AHI Score and 5-year Trend Stumpy Point 80
70 Vigna's Dock
^_ Good DO: *
Chl-a: # 60 Western Basin
*# Fair + 50 DIN: Linear (Crawford * # DO: 40 Dock, r2=0.54) TON: Stumpy Score AHI Fair - Chl-a: Linear (Potato Point DIN: 30 Pt., r2=0.18) %2 Poor TON: 20 Linear (Stumpy %2 Pt., r2=0.01) 10 Linear (Vigna's Eelgrass 2009 0 Dock, r2=0.92) DO: Linear (W. Basin, Eelgrass 2012 Chl-a: 2008 2009 2010 2011 2012 r2=0.01) DIN: %2 %2 Ninigret Pond: Chlorophyll-a Crawford Dock TON: *# 100 Potato Point Vigna's 90 Stumpy Point Potato Dock 80 Point 70 Vigna's Dock
60 Western Basin 50 Linear (Crawford 40 Dock, r2=0.32) AHI Score AHI 30 Linear (Potato Pt., r2=0.67) 20 Linear (Stumpy Pt., r2=0.39) 10 Linear (Vigna's 0 Dock, r2=0.44) Linear (W. Basin, 2008 2009 2010 2011 2012 Mid West r2=0.25) DO: Basin Ninigret Pond: Dissolved Inorganic Nitrogen Crawford Dock Chl-a: %2 100 Potato Point DIN: 90 Stumpy Point TON: 80
70 Vigna's Dock
Crawford's 60 * Western Basin # DO: NA 50 Dock Chl-a: Linear (Crawford 40 Dock, r2=0.35) DIN: Score AHI / 30 Linear (Potato TON: Pt., r2=0.00) Miles 20 Linear (Stumpy 0 0.125 0.25 0.5 0.75 1 1.25 1.5 Pt., r2=0.07 10 Linear (Vigna's RIGIS, URI EDC, RIDEM 0 Dock, r2=0.11) Linear (W. Basin, 2008 2009 2010 2011 2012 r2=0.44) stored eelgrass beds within the pond. Ninigret Pond: Total Organic Nitrogen Crawford Dock The two sites in the western pond 100 Potato Point both had impaired water quality in the 90 Stumpy Point summer of 2012, with a Fair- AHI score 80 at the Crawford’s Dock site and a Poor 70 Vigna's Dock
AHI score at the Mid-Western Basin site. 60 Western Basin Chlorophyll-a scores at both sites were 50 Linear (Crawford Poor, meaning that both sites had high 40
AHI Score AHI Dock, r2=0.28) algae concentrations. Unfortunately, we 30 Linear (Potato Pt., r2=0.74) do not have reliable DO data from the 20 Linear (Stumpy Pt., r2=0.01) Mid-Western Basin site from 2012, but 10 Linear (Vigna's both DIN and TON AHI scores were also 0 Dock, r2=0.34) Linear (W. Basin, 2008 2009 2010 2011 2012 Continued on page 23. r2=0.16) Page 14 Page 15 Salt Ponds Status and Trends 2008 - 2012 Aquatic Health of Green Hill Pond: 2012 Status and 2008 - 2012 Trends
2012 AHI Score and 5-year Trend
^_ Good
*# Fair + %2 * # DO: Fair - DO: Chl-a: Chl-a: Teal %2 Poor DIN: DIN: Rd. TON: Eelgrass 2009 TON: Eelgrass 2012 %2 DO: Chl-a: Indigo DIN: Point TON:
DO:
Chl-a: In Pond * DIN: # TON: Sea %2Lea
Vigna's Dock /
Miles 0 0.125 0.25 0.5
RIGIS, URI EDC, RIDEM
Green Hill Pond: Overall Green Hill Pond is the most impaired 100 In Pond of the six ponds that SPC monitors. It 90 has dense residential development on its 80 Indigo Point shores, many of which until recent years 70 Sea Lea had cesspools or other outdated septic sys- 60 Teal Road tems. There are still cesspools in use near 50 the pond, but they should all be replaced 40 Linear (In Pond, Score AHI r2=0.28) with advanced onsite wastewater treatment 30 Linear (Indigo systems during 2014. In addition to be- 20 Pt., r2=0.30) Linear (Sea Lea, ing impacted by development, Green Hill 10 r2=0.44) Pond’s only water exchange is with neigh- 0 Linear (Teal Rd., r2=0.02) boring Ninigret Pond via a narrow channel 2008 2009 2010 2011 2012 under Creek Bridge. Green Hill Pond has
Salt Ponds Status and Trends 2008 - 2012 Page 16
Green Hill Pond: Dissolved Oxygen Aquatic Health of Green Hill Pond: 2012 Status and 2008 - 2012 Trends 100 90 In Pond 2012 AHI Score and 5-year Trend 80 Indigo Point 70 ^_ Good Sea Lea 60
Teal Road
*# Fair + %2 50 * # 40 Linear (In Pond, DO: Score AHI Fair - r2=0.08) DO: Chl-a: 30 Linear (Indigo Chl-a: Teal DIN: 20 Pt., r2=0.02) %2 Poor DIN: Linear (Sea Lea, Rd. TON: 10 r2=0.00) Eelgrass 2009 TON: 0 Linear (Teal Rd., r2=0.84) Eelgrass 2012 2008 2009 2010 2011 2012 Green Hill Pond: Chlorophyll-a %2 100 DO: 90 In Pond Chl-a: Indigo 80 Indigo Point DIN: Point 70 Sea Lea TON: 60
DO:
50 Teal Road
Chl-a: In Pond * # 40 Linear (In Pond, DIN: Score AHI r2=0.61) TON: Sea 30 Linear (Indigo 20 Pt. r2=0.56) Lea Linear (Sea Lea, 10 r2=0.76) %2 0 Linear (Teal Rd., r2=0.81) 2008 2009 2010 2011 2012 Green Hill Pond: Dissolved Inorganic Nitrogen 100 Vigna's In Pond 90 Dock 80 Indigo Point 70
Sea Lea 60 Teal Road 50 40 Linear (In Pond, AHI Score AHI / 30 r2=0.34) Linear (Indigo Miles 20 Pt., r2=22) 0 0.125 0.25 0.5 10 Linear (Sea Lea, RIGIS, URI EDC, RIDEM r2=0.27) 0 Linear (Teal Rd., 2008 2009 2010 2011 2012 r2=0.76) been closed to shellfishing for decades due Green Hill Pond: Total Organic Nitrogen to bacterial pollution (more on bacterial 100 In Pond testing is in the next section). 90 SPC currently monitors four sites in 80 Indigo Point Green Hill Pond, and all four have degrad- 70
Sea Lea ed water quality. Three of the four sites 60 Teal Road (Sea Lea, Indigo Point, and Teal Road) 50 have Poor AHI scores, and the fourth (In 40 Linear (In Pond, AHI Score AHI r2=0.14) Pond) is Fair-. Furthermore, three of the 30 Linear (Indigo four sites (Sea Lea, Indigo Point, and In 20 Pt., r2=0.69) Linear (Sea Lea, Pond) have declining trends in water qual- 10 r2=0.26) ity, although the r2 values indicate weak fits 0 Linear (Teal Rd., r2=0.84) 2008 2009 2010 2011 2012 Continued on page 24. Page 16 Page 17 Salt Ponds Status and Trends 2008 - 2012 Aquatic Health of Potter Pond: 2012 Status and 2008 - 2012 Trends
2012 AHI Score and 5-year Trend
^_ Good
*# Fair +
* # Fair -
%2 Poor Eelgrass 2009 Eelgrass 2012 North Pond DO: %2 Secchi: Chl-a: DIN: TON:
A cove in northern Potter Pond. DO: Chl-a: DIN: TON:
Mid
Pond * #
* #
West Pond-- Not enough View west toward data Potter Pond from Succotash Rd. Potter Pond: Overall 100 90 80 Mid Pond 70 60 North
50 Linear (Mid Pond, r2=0.36)
Score AHI 40 30 Linear (North, r2=0.12) 20
Miles 10 0 0.125 0.25 0.5 / 0 RIGIS, URI EDC, RIDEM 2008 2009 2010 2011 2012
Salt Ponds Status and Trends 2008 - 2012 Page 18
Potter Pond is situated to the west of Potter Pond: Dissolved Oxygen Point Judith Pond, to which it is connected 100 90 by a channel through a marsh and under 80 Mid Pond the Succotash Rd. bridge. Potter Pond’s 70 only water exchange with the ocean is 60 North via Point Judith Pond through this chan- 50 nel. The north-south orientation of Potter Linear (Mid 40 Pond, r2=0.63) Pond is in contrast to most of the other salt Score AHI 30 Linear (North, ponds, which tend to parallel the coastline. r2=0.42) 20 Potter Pond has year-round residen- 10 tial developments on its shores, as well as 0 several densely populated seasonal neigh- 2008 2009 2010 2011 2012 borhoods (cottages and mobile homes on leased land, plus permanent summer Potter Pond: Chlorophyll-a homes). There is also ongoing agricultural 100 activity adjacent to the western cove of the 90 pond. 80 Mid Pond 70 SPC currently monitors two sites in North Potter Pond—one in the deep (almost 30 60 50 feet) northern basin and one mid-pond, Linear (Mid 40 Pond, r2=0.52) across the pond and southwest of the chan- Score AHI nel. Water quality in the northern basin of 30 Linear (North, r2=0.43) the pond was in the Poor AHI category, but 20 with only three years of monitoring data, 10 a trend cannot be determined. This sec- 0 2008 2009 2010 2011 2012 tion of the pond experiences more limited exchange of seawater due to its distance Potter Pond: Dissolved Inorganic Nitrogen from the channel and also being separated 100 from the rest of the pond by a narrow sec- 90 tion. The mid-pond site had better water 80 Mid Pond 70 quality, but still only in the Fair- AHI cat- North egory. The trend at this site was declin- 60 ing, but with a weak fit of the trendline to 50 Linear (Mid 40 Pond, r2=0.91) the data. The chlorophyll-a AHI scores Score AHI Linear (North, for both sites declined sharply, especially 30 r2=0.63) at the mid-pond site, which went from a 20 chlorophyll-a AHI score of 100 in 2008 10 and 2011 to 0 in 2012. However, the DO 0 Continued on page 24. 2008 2009 2010 2011 2012 Potter Pond: Overall Potter Pond: Total Organic Nitrogen 100 100 90 90 80 Mid Pond 80 Mid Pond 70 70
60 North 60 North 50 50 Linear (Mid Linear (Mid 40 Pond, r2=0.36) Score AHI
Score AHI 40 Pond, r2=0.00) 30 Linear (North, 30 Linear (North, r2=0.12) 20 20 r2=0.10) 10 10 0 0 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012
Page 18 Page 19 Salt Ponds Status and Trends 2008 - 2012 Aquatic Health of Point Judith Pond: 2012 Status and 2008 - 2012 Trends
DO: Secchi: Chl-a: DIN: TON: %2 Ram Point
SPC-guided paddle in the upper pond.
DO: Harbor Island Secchi: Chl-a: DO: DIN: Chl-a: TON: DIN: %2 %2 TON: Gardner Champlin's Island Cove
DO: Chl-a: DIN: TON: Beef Looking west toward Island Snug Harbor and ^_ the channel into Potter Pond.
Great Island DO: 2012 AHI Score Chl-a: East & 5-year Trend DIN: Pond TON: Eelgrass 2009 *# ^_ Good
Eelgrass 2012 Point Judith Pond: Overall Champlin’s Cove
100
*# Fair + Ram Point * # 90 Beef Island Fair - 80 70 East Pond %2 Poor 60 Gardiner Island
Port of 50 Linear (Champ's Galilee 40 Cove, r2=0.68)
Score AHI Linear (Ram Pt., 30 r2=0.21) 20 Linear (Beef Is., r2=0.05) / Linear (East 10 Miles Pond, r2=0.69) 0 0.125 0.25 0.5 0.75 1 0 Linear (Gardiner RIGIS, URI EDC, RIDEM Is., r2=0.93) 2008 2009 2010 2011 2012 Salt Ponds Status and Trends 2008 - 2012 Page 20
Point Judith Pond, which is actually Point Judith Pond: Dissolved Oxygen Champlin’s Cove the estuary where the Saugatucket River 100 Ram Point 90 meets the sea, is oriented north-south Beef Island straddling the South Kingstown-Narra- 80 70 East Pond gansett, RI town line. The Saugatucket Gardiner Island River flows through densely-populated 60 Wakefield and Peace Dale villages, picking 50 Linear (Champ's 40 Cove, r2=0.37) up nutrients and bacteria along the way Score AHI Linear (Ram Pt., from mills and residential and commercial 30 r2=0.35) 20 Linear (Beef Is., development. After the river passes under r2=0.07) 10 Linear (East US Route 1 and enters upper Point Judith 0 Pond, r2=0.31 Pond, the estuary receives additional bac- Linear (Gardiner 2008 2009 2010 2011 2012 Is., r2=0.90) teria and nutrients from more dense devel- opments on the mainland and two islands, Point Judith Pond: Chlorophyll-a Champlin’s Cove plus boating activity at several busy ma- 100 Ram Point 90 rinas. Upper Point Judith Pond has been Beef Island closed to shellfishing for decades, with the 80 East Pond southern boundary of the closure fluctuat- 70 ing frequently. 60 Gardiner Island SPC currently monitors five sites in 50 Linear (Champ's 40 Cove, r2=0.82) Point Judith Pond. Not surprisingly, the Score AHI Linear (Ram Pt., two sites closest to the federally main- 30 r2=0.00) 20 Linear (Beef Is., tained navigation channel into the Point r2=0.09) Judith Harbor of Refuge have the best 10 Linear (East Pond, r2=0.26) water quality: the Beef Island site on the 0 Linear (Gardiner 2008 2009 2010 2011 2012 Is., r2=0.63) west side of the pond had a 2012 AHI score of Good, while the East Pond site Point Judith Pond: Dissolved Inorganic Nitrogen Champlin’s Cove located east of Great Island had an AHI 100 Ram Point score of Fair+. The AHI scores for DO 90 Beef Island and chlorophyll-a at the Beef Island site 80 70 East Pond
were in the Good category but were too variable to determine a trend. TON was 60 Gardiner Island also in the Good category, but DIN was 50 Linear (Champ's 40 Cove, r2=0.29) Fair- and declining, indicating an increase Score AHI Linear (Ram Pt., in nitrogen in the water. Overall, the wa- 30 r2=0.28) 20 Linear (Beef Is., ter quality appeared to be remaining about r2=0.53) the same at the Beef Island site from 2008- 10 Linear (East Pond, r2=0.54) 2012. Water quality at the East Pond site 0 Linear (Gardiner Is., r2=0.86) Continued on page 25. 2008 2009 2010 2011 2012 Point Judith Pond: Overall Champlin’s Cove Point Judith Pond: Total Organic Nitrogen Champlin’s Cove 100 Ram Point 100 Ram Point 90 90 Beef Island Beef Island 80 80 70 East Pond 70 East Pond 60 Gardiner Island 60 Gardiner Island
50 Linear (Champ's 50 Linear (Champ's 40 Cove, r2=0.68) 40 Cove, r2=0.44) Score AHI Linear (Ram Pt., Score AHI Linear (Ram 30 r2=0.21) 30 Point, r2=0.84) 20 Linear (Beef Is., 20 Linear (Beef Is., r2=0.05) r2=0.15) 10 Linear (East 10 Linear (East Pond, r2=0.69) Pond, r2=0.01) 0 Linear (Gardiner 0 Linear (Gardiner 2008 2009 2010 2011 2012 Is., r2=0.93) 2008 2009 2010 2011 2012 Is., r2=0.20)
Page 20 Page 21 Salt Ponds Status and Trends 2008 - 2012 Pond Narratives, continued.
Winnapaug Pond, continued from page 11. nately, this does not tell the whole story. cation). Winnapaug salt marsh. What you hear from “old timers” is that In addition, the Winnapaug Pond used to contain lush pond has, over the eelgrass beds from end to end, so thick years, become heav- that the eelgrass would clog boat pro- ily silted in with pellers. Now, there is no eelgrass any- sand transported where in the pond, and the cause of its through the Weeka- disappearance is not known. Ortho- paug Breachway. photography of Winnapaug pond was This shallowing and studied by the SAV survey team (Brad- shoaling of the pond ley et al, 2013) in both 2009 and 2012, is expanding further but no likely SAV beds were identified and further west each or ground-truthed. Winnapaug will be year. There was a plan examined again in the next state-wide developed in the early survey (M. Bradley, personal communi- 1990’s for dredging the Weekapaug to perform dredging. A great deal of A young fisherman enjoys an afternoon breachway into the pond, study would be necessary to determine on Winnapaug Pond. along with habitat restoration where to dredge, how deeply to dredge, work within the pond. (the and where to place the dredged mate- Army Corps of Engineers rial (on the beach and/or used as marsh South Shore Restoration elevation enhancement). At SPC, we Project). However, funding continue to pursue this issue and we for the project never mate- are hopeful that funding will become rialized and the plan is no available for restoration work in Win- longer valid due to the major napaug Pond. changes to the pond since its development. So unfortu- Photo: M. Bullinger nately, at this time there is no actionable plan or funding
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Quonochontaug Pond, continued from page 13.
For all five sites, the AHI scores for (with corresponding declines in AHI at Shelter Harbor (the peninsula just DIN are all in the Fair- category and scores) is mostly due to ammonium east of the Harmonic Cove Buoy site), are declining, either moderately (East which, our data show, increases from the western end of Quonochontaug Basin Yacht Club, North Bill’s Island, around 30 ug/L in 2008 to 65 ug/L Pond has longer water residence time and Judge’s Rock) or steeply (Har- in 2012. Conversely, nitrate concen- (less frequent turnover of pond water monic Cove Buoy and Harmonic Cove trations show a moderate Paddlers enjoying Quonnie Pond. Channel). This indicates that DIN decrease during this time, (dissolved inorganic nitrogen, which from 18 to 9 ug/L. There is nitrate plus ammonium) concentra- do not appear to be any tions are INCREASING. The plot clear pond-wide trends of the DIN AHI scores demonstrates in total organic nitrogen this—the scores for all sites are tightly concentrations. clustered and all have very strong fits of Due to its distance the trendlines to the data. This strongly from the breachway and increasing trend in DIN concentration the narrowing of the pond
Salt Ponds Status and Trends 2008 - 2012 Page 22 with clean seawater). These longer wa- GIS ArcMap software gave total for a legitimate trend; we will watch these ter residence times and shallower water Quonochontaug Pond of 93 acres in areas closely in future surveys. depths allow for greater consumption 2009 and 71 acres in 2012 Overwashed sand on the pond side of the of dissolved oxygen by algal respiration (RIGIS, 2009 and 2012). Quonochontaug barrier after extratropical and the benthic oxygen demand of or- This is a loss of 22 acres, or storm Sandy. ganic-rich fluid muds. The eastern two 23.7%. Eelgrass beds were sites receive more consistent flushing located throughout the pond with clean ocean water and have overall and many shifted position be- better water quality. tween 2009 and 2012, but the Eelgrass beds, but no widgeon greatest loss in SAV bed size grass, were found in Quonochontaug appeared to be in Harmonic Pond in both the 2009 and 2012 sur- Cove, and to a lesser extent, veys summarized in the 2013 report near Judge’s Rock. Again,
by Bradley et al. Adding up the areas with only two years of data Photo: M. Bullinger of each individual eelgrass bed using it is impossible to determine ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Ninigret Pond, continued from page 15.
Poor. Both Chlorophyll-a and DIN east side of Fort Neck A Salt Pond Safari in Ninigret Pond. had declining trends, but the r2 values (Tautog) Cove, had an indicated weak fits of the trendlines overall AHI score of to the data. Overall, data at the Mid- Fair-. Potato Point, Western Basin site were too variable to located directly across indicate a trend. The same was true of from the breachway, the Crawford Dock site, overall (high had a score of Fair+. variability); DO and TON indicated Vigna’s Dock, located improving AHI scores, while Chloro- nearer the more dense- phyll-a and DIN scores were declining. ly populated section of The Crawford’s Dock site is very near the pond, had an over- the shore, and has a tendency to col- all AHI score of Poor. Two of the three had AHI scores too variable to de- lect dead vegetation pushed against the eastern sites had highly variable AHI termine trends. Chlorophyll-a AHI shore by the wind. Both western sites scores, making determination of a trend scores have weak to moderate declin- receive less frequent supplies of clean impossible. However, the Vigna’s Dock ing trends pond-wide. Hopefully, as we seawater due to their greater distance site had declining water quality, with continue to add more years of data, we from the breachway compared to the declining AHI scores for DO (strongly will get a clearer picture of water qual- sites in the eastern end of the pond. declining), chlorophyll-a, and TON. ity in Ninigret Pond. The three eastern pond testing sites The DIN scores were too variable to The 2009 and 2012 SAV data (RI- also had impaired water quality. The determine a trend. It is interesting to GIS) indicated a modest decline of 10 Stumpy Point site, located at the north- note that Vigna’s Dock had the high- acres (4.9%) in the extent of SAV beds est DIN concentration and the lowest in Ninigret Pond. All of the SAV was DO concentration of the three stations in the eastern half of the pond, nearer in the eastern part of the Pond. It had the Charlestown breachway. The 2012 a much lower chlorophyll-a concentra- dataset also indicated the presence of tion--only 2.9 ug/L. One would think widgeon grass along with the eelgrass with high DIN and low DO that Vi- in far eastern parts of the pond. There gna’s Dock would have higher chloro- was loss of eelgrass meadow acreage in phyll-a concentrations (a surrogate for the vicinity of Stumpy Point, but the phytoplankton productivity). loss was largely offset by gains in the Dredging the Charlestown Breachway. In summary, four out of five of the eastern pond. sampling locations in Ninigret Pond
Page 22 Page 23 Salt Ponds Status and Trends 2008 - 2012 Green Hill Pond, continued from page 17.
Large numbers of resident Canada geese At first look, the fourth site, scores at all four sites in Green Hill contribute nutrients and bacteria to Green Hill Pond’s waters. Teal Road, has water quality that Pond were below 10, indicating an appears to be in the Poor AHI abundance of organic nitrogen such as category but stable. However, algae in the water. This is supported by looking more closely at the AHI the very low chlorophyll-a AHI scores scores for the individual param- at all four sites in 2011 and 2012, which eters at this site tells a conflict- indicate a high concentration of phyto- ing story. The DO AHI score is plankton in the water. in the Good category and DIN Unfortunately, Green Hill Pond’s is Fair-. However, both of these water quality seems to be continuing to parameters show strong improv- decline. As in Ninigret, chlorophyll-a of the trendlines to the data. At the ing trends supported by strong fits of AHI scores are declining pond-wide. Sea Lea site, which is located within the trendlines to the data. The DO This decline is also apparent in the loss a cove surrounded by dense neighbor- AHI score at this site improved from of 47 acres, or 34.1%, of Green Hill hoods, chlorophyll-a, DIN, and TON Poor to Good in five years, while the Pond’s SAV between 2009 and 2012 were all declining or strongly declining. DIN score improved from AHI=0 three (RIGIS). All of the SAV disappeared The DO AHI scores were too vari- years in a row to Fair-. Conversely, the from the eastern end of the pond, and able to determine a trend. At the In- chlorophyll-a and TON AHI scores the size of the SAV bed in the western digo Point site, chlorophyll-a and TON are both Poor and showing strong side of the pond (which also contains were declining, but DO and DIN were declining trends, both supported by widgeon grass) decreased. too variable to infer a trend. However, strong fits of the trendlines to the data. DIN concentrations are declining with The chlorophyll-a scores Even with its challenges, Green Hill Pond time. The In Pond site has a confus- went from Fair- to Poor, is a beautiful place to explore by kayak. ing mix of Good to Poor AHI scores with AHI scores of 0 for the testing parameters and trends, in 2011 and 2012. The along with a lot of variability. As with TON AHI scores de- the Indigo Point site, DIN concentra- clined similarly, going tions are declining with time. Hope- from (barely) Fair+ in fully, adding more years of data will al- 2008 to Poor, also with low better assessment of what is going scores of 0 in 2011 and at this site. 2012. In fact, the TON
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Potter Pond, continued from page 19. scores at both sites show an improving pond site is declining, with a strong fit the northern basin and southwestern trend. The DIN AHI score at the mid- of the trendline to the data. The TON cove of the pond in the 2009 SAV sur- scores at both sites vey were not present in 2012, account- Potter Pond on a perfect autumn day. were too variable to ing for much of the lost acreage. Other determine a trend. SAV beds shifted location but were still Potter Pond present, and even increased in extent in lost about 8 acres, some locations mid-pond. or 10.7%, of its Salt Ponds Coalition participated SAV bed acre- in the ground-truthing of the Potter age between 2009 Pond eelgrass delineations in 2009 and and 2012 (RIGIS). looks forward to participating in map- The eelgrass mead- ping the extent of SAV in the coastal ows observed in ponds in future surveys.
Salt Ponds Status and Trends 2008 - 2012 Page 24 Point Judith Pond, continued from page 21.
declined from the Good category in The Cham- Point Judith Pond on a typical summer day. 2008-2011 to just under the Good/ plin’s Cove site Fair+ threshold (AHI=65) in 2012. is adjacent to Three individual indicators at that site Harbor Island, declined: DO, chlorophyll-a, and DIN. which is densely The TON AHI scores remained stable. populated and On densely populated Great Island, all not served by homes are served by onsite wastewater sewers. Cham- treatment systems. Fortunately the is- plin’s Cove also land is close to the navigation channel, receives restricted which allows water exchange with the flushing with clean seawater. In 2012, though not steeply and with a weak fit Point Judith Harbor of Refuge. AHI scores for the Champlin’s Cove of the trendline to the data. However, The three monitoring sites in the site ranged from Fair+ (DIN) to Poor the TON AHI scores are declining upper half of the pond all had impaired (chlorophyll-a and TON). Three pa- sharply, with a moderately strong fit of water quality, with AHI scores of Poor. rameters (DO, chlorophyll-a, and the trendline to the data. This shows an Furthermore, at the Gardner Island TON) had declining trends, while the increasing amount of organic nitrogen and Champlin’s Cove sites water qual- DIN AHI scores are remaining about in the water, as indicated by strongly ity is declining. At the Gardner Island the same. increasing chlorophyll-a concentra- site, the 2012 scores for all parameters The Ram Point site, at were either Fair- or Poor. The AHI the northern tip of Point Kids from Camp Fuller work on their sailing skills in western scores for DO, Secchi depth, chlo- Judith Pond where the Sau- Point Judith Pond. rophyll-a, and DIN were all strongly gatucket River enters the declining, while the TON AHI scores “pond,” had a 2012 AHI were too variable to determine a trend. score of Poor, but overall The difference in DIN concentrations is not showing an improv- for surface water and bottom water at ing or declining trend. The the Gardner Island site is the largest for AHI score at this site is all five salt ponds, suggesting that bot- a somewhat unexpected tom sediment release of ammonium is Good for DO, but Poor for an important process affecting its poor all of the other parameters. water quality. However, looking at the trends in the tions. Hopefully, the 2013 monitoring
SPC ground-truthing eelgrass beds AHI scores reveals a confusing mixed data will bring the situation at Ram in Potter Pond (2009). bag of improvements and declines. The Point into clearer focus. Note the flounder scores for DO and DIN are improving, Point Judith Pond was the only salt in the center of the photo but with weak fits of the trendlines to pond that had an overall increase in the at right. the data. Secchi depth is declining, al- extent of its SAV beds between 2009 and 2012 (RIGIS). The total acrage of eelgrass meadows increased by 7 acres, or 7.4% (RIGIS). Two 2009 eelgrass beds totaling about 7 acres at the west- ern side of the pond near the Beef Is- land sampling site were not present in 2012. However, the extent of the eel- grass beds in the eastern pond nearly doubled, from about 16 acres to about 30 acres. In the south-central part of the pond, the extent of the SAV beds remained about the same (about 70 acres total).
Page 24 Page 25 Salt Ponds Status and Trends 2008 - 2012 Bacteria Data Winnapaug Pond Enterococci Winnapaug Pond Fecal Coliforms Bacterial data from the SPC moni- words, 40 individual water samples had 250 250 toring sites from 2008 – 2012 indi- bacteria levels (enterococci, fecal coli- 225 225 cate that high bacteria levels are rare- form, or both) that exceeded RI stan- 200 200 ly a problem at most locations in the dards out of 1,295 total samples, or 175 Southwest Corner 175 150 150 ponds. As a reminder from page 8, the 3.1% of samples. Southwest Corner RI DEM enterococci primary contact The yearly average enterococci and 125 East Basin 125 recreational/swimming single sample fecal coliform concentrations (see plots 100 100 East Basin MPN/100 mL criterion is 104 MPN (most probable at right and next page) never exceeded 75 Enterococci limit, MPN/100 mL 75 number of bacteria) per 100 milliliters the State of RI standards in either Win- 50 single sample 50 (ml) of water. For fecal coliform bac- napaug or Potter Ponds. Five sampling 25 25 teria, the RI DEM saltwater primary sites (Winnapaug Pond Southwest 0 0 contact recreational/swimming single Corner; Quonochontaug Pond East 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012 sample criterion is that not more than Basin Yacht Club and Harmonic Cove 10% of the total samples taken shall ex- Buoy; Potter Pond North, and Point Quonochontaug Pond Enterococci Quonochontaug Pond Fecal Coliforms ceed 400 MPN/100 ml. Judith Pond Gardiner Island) had one 250 250 Bacterial levels in samples from the sample during the five years exceed the 225 East Basin Yacht 225 East Basin Yacht monitoring sites included in this report RI criterion for enterococci but never 200 Club 200 Club exceeded the RI DEM single sample for fecal coliform. 175 Harmonic Cove 175 Harmonic Cove Buoy 150 Buoy criteria 48 times in five years. Most of In Quonochontaug Pond, the aver- Harmonic Cove 150 Harmonic Cove these incidents were exceeded entero- age enterococci (but not average fecal 125 Channel 125 Channel cocci levels (39 times). Fecal coliform coliform) concentration exceeded the 100 Judge’s Rock 100 Judge’s Rock MPN/100 mL levels exceeded the criterion nine times; RI criterion at one site during one year: 75 MPN/100 mL 75 North of Bill’s eight of these were in the same water Harmonic Cove Channel in 2011. 50 Island 50 North of Bill’s sample as exceeded enterococci levels This was the result of the October 2011 25 Enterococci limit, 25 Island (a single water sample is used to deter- sample having an enterococci value of 0 single sample 0 mine both types of bacteria). In other 697 MPN/100 mL. The same sample 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012 Ninigret Pond Enterococci Ninigret Pond Fecal Coliforms 250 250 225 Crawford Dock 225 Crawford Dock 200 200 175 Potato Point 175 Potato Point 150 150 Stumpy Point 125 125 Stumpy Point 100 100 Vigna's Dock Vigna's Dock MPN/100 mL MPN/100 mL 75 75 50 Western Basin 50 Western Basin 25 25 0 Enterococci limit, 0 single sample 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012 yielded a fecal coliform concentration of 531 (the RI standard is 400), but this was not enough to push the yearly av- erage over 400. This site had one other sample that exceeded the enterococci standard, but not the fecal coliform Potential sources of bacteria in the salt ponds: 1. farms; 2. pet waste; 3. waterfowl standard—in October 2012. waste washed in by rain; 4. waterfowl waste deposited directly in the water; 5. other wildlife; 6. storm water runoff; 7. septic systems, especially outdated or failing (e.g., Ninigret Pond had three out of five cesspools); 8. septic waste from boats. sites with elevated bacterial levels. The
Salt Ponds Status and Trends 2008 - 2012 Page 26 Winnapaug Pond Enterococci Winnapaug Pond Fecal Coliforms 250 250 225 225 200 200 175 Southwest Corner 175 150 150 Southwest Corner 125 East Basin 125 100 100 East Basin MPN/100 mL
75 Enterococci limit, MPN/100 mL 75 50 single sample 50 25 25 0 0 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012 Quonochontaug Pond Enterococci Quonochontaug Pond Fecal Coliforms 250 250 225 East Basin Yacht 225 East Basin Yacht 200 Club 200 Club 175 Harmonic Cove 175 Harmonic Cove Buoy 150 Buoy Harmonic Cove 150 Harmonic Cove 125 Channel 125 Channel 100 Judge’s Rock 100 Judge’s Rock MPN/100 mL 75 MPN/100 mL 75 North of Bill’s 50 Island 50 North of Bill’s 25 Enterococci limit, 25 Island 0 single sample 0 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012 Ninigret Pond Enterococci Ninigret Pond Fecal Coliforms 250 250 225 Crawford Dock 225 Crawford Dock 200 200 175 Potato Point 175 Potato Point 150 150 Stumpy Point 125 125 Stumpy Point 100 100 Vigna's Dock Vigna's Dock MPN/100 mL MPN/100 mL 75 75 50 Western Basin 50 Western Basin 25 25 0 Enterococci limit, 0 single sample 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012 yearly average enterococci concentra- Dock sites each exceeded the entero- those samples, the fecal coliform cri- tion exceeded the RI standard at the cocci criterion twice, and both were terion was also exceeded (September Crawford Dock site one year (2011) in the same months: August of 2009 of 2011). The Crawford Dock site is and at the Vigna’s Dock site in two and July of 2010. The samples from near the shore at the far western end years (2009 and 2010). No site had a Crawford Dock during those two of Ninigret Pond. This location tends yearly average fecal coliform concen- months also exceeded the enterococci to accumulate dead plant material and tration that exceeded the RI standard criterion. At the Crawford Dock site, doesn’t have as frequent water exchange for recreational contact. In Ninigret the enterococci criterion was exceeded with cleaner ocean water as other parts Pond, the Potato Point and Vigna’s in four additional samples; in one of of the pond.
Page 26 Page 27 Salt Ponds Status and Trends 2008 - 2012 Green Hill Pond has been closed restricted channel from neighboring Green Hill Pond Enterococci Green Hill Pond Fecal Coliforms to shellfishing for over a decade due to Ninigret Pond. In addition, Green Hill 250 250 bacterial contamination. Rhode Island Pond receives runoff and freshwater in- 225 In Pond 225 adheres to bacterial (fecal coliform) put from several sources, all of which 200 200 standards set by the National Shellfish add to the bacterial load. Green Hill In Pond 175 Indigo Point 175 Sanitation Program in determining ar- Pond fecal coliform bacteria counts ap- 150 150 Indigo Point eas closed to shellfishing. That standard pear to be increasing with time, 2009 125 Sea Lea 125 requires that the median (geographic to 2012. 100 100 Sea Lea MPN/100 mL mean or MPN, or most probable num- Point Judith Pond had only one 75 Teal Road MPN/100 mL 75 ber) fecal coliform bacteria level shall sampling location with bacteria con- 50 50 Teal Road not exceed 14 (colonies) per 100 ml centration problems: Ram Point. Both 25 Enterococci limit, 25 90% of the time. the yearly average enterococci and fe- 0 single sample 0 While the yearly average fecal co- cal coliform concentrations exceeded 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012 liform concentrations did not exceed RI criteria in 2008. However, the plots the RI recreational contact standard of both bacterial forms indicate that Potter Pond Enterococci Potter Pond Fecal Coliforms for any site, the average enterococci concentrations have improved since 250 250 concentration at the Teal Road site that year. In 2008, 2009, and 2010, two 225 225 did—in 2010. All 15 of the individual samples in each year exceeded RI crite- 200 200 samples from Green Hill Pond that ria: in 2008 and 2010, for both entero- 175 175 exceeded RI criteria for bacteria were cocci and fecal coliform, and in 2009 Mid Pond 150 150 from Indigo Point (six samples) and for enterococci only. In 2011 and 2012, Mid Pond 125 125 Teal Road (nine samples), and all but one sample in each year exceeded RI North 100 100 North one were high enterococci concentra- criteria for both bacterial forms. Ram MPN/100 mL MPN/100 mL 75 75 tions (the Indigo Point August 2011 Point is located at the northern end of Enterococci limit, 50 single sample sample exceeded the fecal coliform Point Judith Pond where there is dense 50 standard). These two sites had samples development, freshwater input from 25 25 that exceeded the state criteria all five the Saugatucket River (which also runs 0 0 years. Green Hill Pond has dense de- through densely developed Wakefield), 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012 velopment on its shores and receives and limited flushing with clean seawa- very limited clean seawater through a ter due to its distance from the channel Point Judith Pond Enterococci Point Judith Pond Fecal Coliforms 500 500 450 450 Champlin’s Cove Champlin’s Cove 400 400 Ram Point 350 Ram Point 350 300 300 Beef Island Beef Island 250 250 200 East Pond 200 East Pond MPN/100 mL 150 MPN/100 mL 150 100 Gardiner Island 100 Gardiner Island 50 50 Enterococci limit, Fecal coliform limit, 0 single sample 0 single sample 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012
to the Harbor of Refuge. There are also several busy marinas and limited waste pumpout stations. In summary, the vast majority of the SPC samples showed little problem with bacterial contamination in the ponds. Problem areas were limited to a Diagram of an advanced onsite wastewater treatment system (figure from University of Rhode Island Onsite Wastewater Resource Center). few areas with known issues. We hope
Salt Ponds Status and Trends 2008 - 2012 Page 28 Green Hill Pond Enterococci Green Hill Pond Fecal Coliforms 250 250 225 In Pond 225 200 200 In Pond 175 Indigo Point 175 150 150 Indigo Point 125 Sea Lea 125 100 100 Sea Lea MPN/100 mL
75 Teal Road MPN/100 mL 75 50 50 Teal Road 25 Enterococci limit, 25 0 single sample 0 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012 Potter Pond Enterococci Potter Pond Fecal Coliforms 250 250 225 225 200 200 175 Mid Pond 175 150 150 Mid Pond 125 North 125 100 100 North MPN/100 mL MPN/100 mL 75 Enterococci limit, 75 50 single sample 50 25 25 0 0 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012 Point Judith Pond Enterococci Point Judith Pond Fecal Coliforms 500 500 450 450 Champlin’s Cove Champlin’s Cove 400 400 Ram Point 350 Ram Point 350 300 300 Beef Island Beef Island 250 250 200 East Pond 200 East Pond MPN/100 mL 150 MPN/100 mL 150 100 Gardiner Island 100 Gardiner Island 50 50 Enterococci limit, Fecal coliform limit, 0 single sample 0 single sample 2008 2009 2010 2011 2012 2008 2009 2010 2011 2012
that continuing replacement of outdat- ce/wq/RESOURCES/wastewater/ ed and failing septic systems with ad- Onsite_Systems/Advanced/index.htm. vanced treatment systems (see figure at Ongoing waterfowl control measures left) will continue to improve bacteria (Canada goose egg oiling, riparian buf- concentrations. For more information fer installations, and educating people on these advanced treatment systems, to not feed waterfowl), plus better han- visit the URI Onsite Wastewater Re- dling of storm water, will also benefit source Center website at www.uri.edu/ the cleanliness of the ponds.
Page 28 Page 29 Salt Ponds Status and Trends 2008 - 2012 Pond Stewardship: What We All Can Do to Help Improve Water Quality
Human activities in the ponds and on their surrounding water- sheds affect the waters of the ponds. The ways in which we choose to live, work, and/or recreate in or near the salt ponds can have real pos- itive or negative impacts. Using excess fertilizer, leaving pet waste on the ground, feeding waterfowl, improperly disposing of waste from boat holding tanks, continuing to use outdated or failing septic sys- tems, and allowing stormwater to run freely into the ponds all can adversely affect water quality. People live near, work in, and play on the salt ponds because they appreciate their beauty and enjoy their benefits--nobody wants to inadvertently harm the beautiful pond that drew them to the area. Here are some simple steps that people can take to protect water quality in the salt ponds.
Rain barrels and rain gardens catch roof runoff before it can pick up fertilizers, pet waste, and goose droppings and carry them into the pond. Water from rain barrels can be used in gardens during dry spells and outdoor water bans.
A vegetated buffer of native plants is beau- tiful, plus it catches yard runoff and discourages Canada geese from walking out of the pond onto your lawn.
Photo: a nice rain garden at the Sci- tuate, RI tax asses- sor’s office, near the Scituate Reservoir.
Pet waste contains high levels of nutrients and bacteria. Cleaning up after pets prevents these from washing into the pond. Please seal the waste tightly in a plastic bag and put it in the trash.
Photo: coz.southernfriedscience.com
Salt Ponds Status and Trends 2008 - 2012 Page 30 Pond Stewardship: What We All Can Do to Help Improve Water Quality
Watch Your Fertilizer Use Near the Ponds
Fertilizer not used by plants ends up in the pond...
where it causes excess algae growth...
which reduces water clarity; decomposition uses oxygen...
very low oxygen can cause kills of shellfish and finfish
* Use fertilizer sparingly or not at all. * If you must fertilize, use organic or low-soluble inorganic fertilizer. * Have your soil tested to determine your lawn’s needs (if any) to avoid overfertilizing. * Ensure that excess fertilizer does not reach the pond by sweeping any fertilizer that spills onto driveways or walkways into the grass. * Fertilize once or twice per year; not after late October. * Older (10+ years) lawns need less fertilizer. * Consider using organic methods--healthy, resilient lawns and yards need fewer fertilizers and pesticides.
Lawn Maintenance Tips: * Mow high (3”) and leave clippings on the lawn. * Reduce excessive or frequent/shallow irrigation. Too much water moves nitrogen below the root zone; frequent/shallow watering encourages shallow root zones and weak plants. * Aerate and thatch to reduce compaction. * Shift to fescue grasses, which need less nitrogen and water
Geese don’t like places where there is cover in which a predator can hide, so shrubs near the water will discourage them. And please don’t feed the geese!
Try to be a “green” boater: * Limit use of cleaning agents that can wash into the pond; use non-toxic and biodegradable products whenever possible. * Use pumpout facilities to empty holding tanks.
Page 30 Page 31 Salt Ponds Status and Trends 2008 - 2012 Salt Ponds Coalition: A Brief History
Mission: To protect and enhance the health of the salt ponds for the benefit of wildlife and people.
The coastal lagoons, or salt ponds, of southern Rhode Island are a regional treasure. They are shallow brackish-to-marine bodies of water separated from the ocean by coast- al barriers. They support productive habitat and diverse wildlife, including shorebirds, mammals, fish, and shellfish. They are also valued highly by people who enjoy their natural beauty and special time spent in and on pond waters. The ponds are critical habitat to a multitude of commercially and recreationally important fish and shellfish, and contribute substantially to two of Rhode Island’s largest industries: tourism and fisheries.
Salt Ponds Coalition (SPC) recognizes that humans are an important part of the salt pond ecosystem. Along with the benefits we enjoy from the ecosystem services of the ponds, we have a responsibility to be stewards of the ponds to ensure that they continue to provide these services for generations to come. Not only does this benefit us, but it benefits the important habitat and abundant wildlife in the ponds.
SPC has an almost three-decade history. The Pondwatcher Program began with a grant from the University of Rhode Island (URI) Sea Grant program in 1984. SPC, formed shortly thereafter, was a merger of several neighborhood salt pond advocacy groups covering the south coastal region of Rhode Island from Watch Hill to Point Judith. SPC was incorporated as a 501(c)(3) educational and advocacy non-profit organiza- tion in 1985. The Pondwatcher program became part of SPC and recently completed its 28th year of water quality monitoring. In 2003, SPC was designated by the State of Rhode Island as the official watershed council for the salt ponds region. Thus, SPC be- came the recognized spokespersons to participate in local and state regulatory forums and policy development.
SPC’s activities in support of our mission include: • Water Quality Monitoring • Research • Data Analysis and Dissemination • Communication • Advocacy and Outreach • Restoration/Conservation • Education and Exploration • Watchdog
P.O. Box 875, Charlestown, RI 02813 (401) 322-3068 [email protected] www.saltpondscoalition.org