July 29, Report Date: September 8, 2009 Technical Report #

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1 1 Bacterial Assessment: Weeks Pond, Atkins Brook, Winn s Brook July 29, 2009 Report Date: September 8, 2009 Technical Report # Summary: This report documents the results of a single monitoring event that took place at Weeks Pond, Turtle Pond, Winn s Brook, Atkins Brook and associated tributaries and outfalls in Belmont, MA. Monitoring took place during dry weather conditions. Bacteria counts at levels that fail to meet the Massachusetts Department of Environmental Protection State Water Quality Standards for primary contact / swimming were documented at two sites, Tributaries 2 and 3 of Weeks Pond. Further evaluation is required to establish whether these bacteria levels are the result of wildlife or the result of infiltration of septic systems. This evaluation could begin with simple tests for levels of ammonia and optical brighteners in the tributaries.

2 2 CITATION This report was prepared by: Mystic River Watershed Association 20 Academy St. Suite 306 Arlington, MA Principal Investigators: Patrick Herron, PhD Roger Frymire Water Quality Monitors: Roger Frymire Lab Analysis: EPA Region 1 Laboratory, Chelmsford MA This report describes monitoring data collected by MyRWA under its MassDEP and EPAapproved Quality Assurance Project Plan with funding support from the Boston Foundation, the Caswell Foundation and funding from an anonymous foundation. This report should be cited in the literature in the following manner: Bacterial Assessment: Weeks Pond, Atkins Brook, Winn s Brook, July 29, 2009 Technical Report Mystic River Watershed Association, Arlington, MA. September 8, 2009 MYSTIC RIVER WATERSHED ASSOCIATION Technical Report #:

3 3 Table of Contents 1. Cover Sheet 2. Citation information 3. Table of Contents 4. Executive Summary a. Conclusions and Action Items 5. Base report a. Introduction b. Methods c. Results 6. Quality Assurance, Quality Control, and Data Validation 7. Tables and Figures Maps Site Information September 8, 2009 MYSTIC RIVER WATERSHED ASSOCIATION Technical Report #:

4 4 Executive Summary Bacterial Monitoring Results: July 29, 2009 MyRWA conducted a single monitoring event on the morning of July 29, 2009 in which grab samples were tested for bacteria. Samples were collected in dry conditions with total amount of precipitation during the previous 48 hours equal to Overall, the measured water quality parameters indicated normal water quality in most areas tested. However, a few sites stood out as deserving further investigation due to relatively high bacteria counts or high salinity. Tributaries 2 and 3 both had counts of E. coli that exceeded the Ma-DEP State Water Quality Standards for primary contact/ swimming with values of 324 and 572 MPN (most probable number) bacteria / ml. This level of bacteria could be the result of the activity of wildlife or the result of leaking septic systems. Further evaluation could be accomplished with low-cost testing of other indicators of human generated sewage: optical brighteners (present in clothes detergents) and ammonia. By taking samples in a sequential manner from source to outlet into Weeks Pond, a potential source of nutrients or bacteria could be identified. Atkins Brook at Somerset had elevated E. coli values of 233 MPN/100 ml. It is important to restate however, that bacteria levels found at all three of these sites could be the result of wildlife activity. Weeks Pond has significant amount of duckweed (Lemna sp.) and Turtle Pond has some submerged vegetation (as observed caught on outlet grate). The level of duckweed in Weeks Pond is characteristic of ponds with moderate sources of nutrients and low outlet flow such that duckweed is never leaving the system. The relatively low dissolved oxygen numbers at the outlets of both Turtle and Weeks Pond is likely the result of the aquatic vegetation respiring and drawing down oxygen values at night. We would expect that levels of dissolved oxygen would be much higher during later in the day. The salinity levels at Tributary 3 of Weeks Pond were relatively high (0.8 mg/l). During much of the summer, salinity values throughout the freshwater parts of the Mystic River Watershed usually range from 0.1 to 0.5 mg/l. Conclusions and Action Items: 1. Tributary 2 and 3 of Weeks Pond: MyRWA would recommend testing in both tributaries for ammonia and optical brighteners to help determine whether bacteria levels are the result of human activity or natural sources. 2. Tributary 3 of Weeks Pond: MyRWA recommends a visual survey of the local environment, roads and business to provide clues as to the cause of the relatively high salinity. September 8, 2009 MYSTIC RIVER WATERSHED ASSOCIATION Technical Report #:

5 5 Introduction Background. The Mystic Monitoring Network (MMN) was created in 2000 by the Mystic River Watershed Association (MyRWA) to collect valuable water quality data along the Mystic River and its tributaries. The MMN is a volunteer-based project that is made up of trained citizen volunteers, student interns, and scientific advisors throughout the region. The goals of the MMN are to establish a high quality baseline of data for the Mystic River Watershed, identify and address water pollution problems, raise public, municipal and state agency awareness of water quality in the Mystic, and create a network of informed and active citizen advocates. MMN s Hot Spot monitoring program at MyRWA allows the organization to test water quality in locations not regularly sampled in our baseline program or that are suspected of having problems with bacteria loading. Methods Water quality samples are always collected by trained MyRWA staff and volunteers following the protocol written in MyRWA s Quality Assurance Project Plan (QAPP). For centerline locations, bacteria samples are collected directly from the river and for endof-pipe samples, water is collected directly from the outfall. In fresh water, samples are analyzed for the bacteria E. coli and in saltwater, samples are analyzed for the presence of Enterococcus. The bacteria samples are collected in sterile containers containing a sodium thiosulfate tablet and kept on ice until delivery to either the EPA lab in Chelmsford, or MyRWA s lab at Tufts University. Samples are analyzed using the Colilert method for enumerating colony forming units (cfu) of bacteria. Physical habitat parameters are measured according to the QAPP. A YSI meter is used to collect measurements for water temperature, dissolved oxygen, specific conductivity, and salinity. The coordinates of each sample location are recorded with a Garmin 76Cx GPS unit. Air temperature is recorded with an alcohol thermometer at the beginning and end of the sampling period. Data on precipitation during the past 48 hours are obtained from the USGS website (real-time data for stream gage located at Muddy River in Brookline: Results Below, tables and graphs summarize the results of bacteria sampling during the monitoring event. ND = bacteria not detected in sample. Each water body we tested is September 8, 2009 MYSTIC RIVER WATERSHED ASSOCIATION Technical Report #:

6 6 a Class B water body, and any bacteria level above 235 cfu/100 ml E. coli or 104 cfu/100 ml Enterococcus is a violation of the state water quality standard for bacteria. September 8, 2009 MYSTIC RIVER WATERSHED ASSOCIATION Technical Report #:

7 7 Quality Assurance Quality control procedures have been documented for each parameter tested by MyRWA, and can be reviewed in Table B5-1 of the QAPP (approved December 2006). Quality control of data is ensured in several ways. YSI meters are subjected to pre- and post-calibration for each sampling event. Thermometers are calibrated on an annual basis. GIS coordinates are marked at an accuracy of 20. As discussed in the QAPP, field duplicates are not collected due to the heterogeneous nature of bacteria in an aquatic medium. EPA Region 1 Laboratory has submitted a copy of their quality assurance plan and standard operating procedures. They do not submit results of their quality control measures, such as relative percent difference, but QC protocol are followed according to their standard operating procedures (available on request). During this sample event, no violations of QC occurred. All samples were delivered to the EPA lab within the designated holding time, and the EPA lab did not report any violations of their standards. Data received from the EPA lab and collected from the field were entered into MyRWA s Excel database by the Project Manager and were checked for error by another staff person. No changes to the data entry were made. Following the QAPP, these data, as reported here, are sent to the Department of Public Works and the Board of Health of the relevant municipalities. After 30 days, the data will be sent to MassDEP, the EPA, conservation commissions of the relevant communities, and any other stakeholders that have expressed interest in receiving water quality data. September 8, 2009 MYSTIC RIVER WATERSHED ASSOCIATION Technical Report #:

8 Location Water Bodies Hot Spot Sample Date Rain Events (past 48 hours) Air Temp, beginning and ending Monitors Lab Belmont Weeks Pond, Atkins Brook, Winns Brook 7/29/ " 7/29, 0" 7/28, 0.15" 7/27 R. Frymire EPA Region 1 - Chelmsford Sample # Site ID E coli cfu/100ml H2O Temp. C DO mg/l Sp. Cond. μs/cm Salinity Time (AM) Type Comments GPS Waypoint 1788 TURTOUT :44 Turtle Pond Outlet ATB :00 Atkins Brook u/s Wee WEEKT :07 Trib1 to Weeks Pond WEEKT1S ND :12 Headwater Spring to T WEEKT :17 Trib2 to Weeks Pond WEEKT :22 Trib3 to Weeks Pond WEEKOUT :28 Outlet from Weeks Po ATB :39 Atkins Brook@Somer WIB :46 Winns Brook U/S Atki WIB :07 Winns Brook U/S Atki WIB : WIBUTB :25 Un-named trib B to W 22 Data Entry PMH Data QA: JRR

9 E. coli MPN/100ml Location Belmont Water Bodies Weeks Pond, Atkins Brook, Winns Brook Hot Spot Sample Date 7/29/2009 Rain Events (past 48 hours).04" 7/29, 0" 7/28, 0.15" 7/27 Air Temp, beginning and ending - Monitors R. Frymire Lab EPA Region 1 - Chelmsford 700 Bacterial Monitoring Weeks Pond, Winn and Atkins Brook July 29, Primary Contact/Swimming standard: 235 E. coli MPN/ 100 ml Site ID Figure 1. Bacteria counts from samples collected by MyRWA on 07/29/09 during Hotspot sampling event in Belmont at Weeks Pond, Turtle Pond, Winns and Atkins Brook. Two of twelve samples failed to meet water quality standards for primary contact/swimming in a Class B water body (235 MPN/100 ml). See maps and site descriptions for information on sampling locations. MyRWA Hot Spot Monitoring July 29, 2009 Weeks Pond, Atkins and Winns Brook, Belmont

10 Location Belmont Water Bodies Weeks Pond, Atkins Brook, Winns Brook Hot Spot Sample Date 7/29/2009 Rain Events (past 48 hours).04" 7/29, 0" 7/28, 0.15" 7/27 Air Temp, beginning and ending - Monitors R. Frymire Lab EPA Region 1 - Chelmsford Blue labels = water quality standards met (E. coli concentrations < 235 cfu / 100 ml) Yellow labels = primary contact / swimming standards not met (E. coli between cfu / 100 ml) Red labels - secondary contact / boating standards not met (E. coli > 1260 cfu / 100 ml) Figure 1. Location of all Hotspot sampling in Belmont, MA on July 29,2009. Sites were all located south of Route 2. and west of Route 60. The white bar on the left of figure represents a distance of 0.5 MyRWA Hot Spot Monitoring July 29, 2009 Weeks Pond, Atkins and Winns Brook, Belmont

11 Figure 2. Location of all Hotspot sampling in Belmont, MA on July 29,2009. Figure 3. Location of all sampling in immediate vicinity of Weeks Pond, Belmont, MA MyRWA Hot Spot Monitoring July 29, 2009 Weeks Pond, Atkins and Winns Brook, Belmont

12 Figure 4. Location of all sampling in immediate vicinity of Weeks Pond, Belmont, MA. White bar on left represents 10 m. MyRWA Hot Spot Monitoring July 29, 2009 Weeks Pond, Atkins and Winns Brook, Belmont

13 Location Water Bodies Hot Spot Sample Date Rain Events (past 48 hours) Air Temp, beginning and ending Monitors Lab Belmont Weeks Pond, Atkins Brook, Winns Brook 7/29/ " 7/29, 0" 7/28, 0.15" 7/27 - R. Frymire EPA Region 1 - Chelmsford Sample Site Town Water Body Latitude Longitude Directions Turtle Pond Outlet located behind Track at 1788 TURTOUT Belmont Turtle Pond Belmont Hill School at Marsh St. Short walk (80 meters) upstream on Atkins 1789 ATB005 Belmont Atkins Brook Brook located in Northwest corner of Weeks Pond 1790 WEEKT1 Belmont Tributary 1 to Weeks Pond Short walk (~10 meters) up Tributary 1 located at Southwest corner of Weeks Pond 1791 WEEKT1S Belmont Headwater Spring to Tributary 1 Short walk (~25 meters) up Tributary 1 located at Southwest corner of Weeks Pond 1792 WEEKT2 Belmont Tributary 2 to Weeks Pond Located just to the East of Tributary 1 on South Side of Weeks Pond 1793 WEEKT3 Belmont Tributary 3 to Weeks Pond Short walk (~10 meters) up Tributary 3 located at Southeastt corner of Weeks Pond 1794 WEEKOUT Belmont Outlet from Weeks Pond Located at Northeast corner of Weeks Pond 1795 ATB003 Belmont Atkins Brook Atkins Brook at Somerset Rd 1796 WIB015 Belmont Winns Brook Winns Brook upstream of Atkins Brook, located at end of Shady Brook Ln 1797 WIB013 Belmont Winns Brook Winns Brook upstream of Atkins Brook, located on Howells Rd WIB012 Belmont Winns Brook Winns Brook located at Clifton St WIBUTB Belmont Un-named trib B to Winns Brook Located at corner of Prospect and Clifton St.