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HomeMy WebLinkAboutPY6 Catchment Investigations Memo40 Shattuck Road | Suite 110 Andover, Massachusetts 01810 www.woodardcurran.com T 800.426.4262 T 978.557.8150 F 978.557.7948 MEMORANDUM TO: John Livsey, Director of Public Works – Town of Lexington Marissa Liggiero, Senior Civil Engineer – Town of Lexington FROM: Garrett Bergey, Project Manager – Woodard & Curran James Sharrard, Technical Manager – Woodard & Curran Margaret Byrne, Project Scientist – Woodard & Curran Leah Finn-Erb, Technical Specialist – Woodard & Curran DATE: July 9, 2024 RE:MS4 General Permit Compliance Illicit Discharge Detection and Elimination Program Permit Year 6 Catchment Investigation Summary EXECUTIVE SUMMARY Between July 2023 and October 2023, drainage infrastructure within twenty-eight catchments in the Town of Lexington, Massachusetts (Town) were inspected during dry weather conditions for evidence of non-stormwater discharges. Results are summarized in the following findings: Potential Illicit Discharges •Dry weather flow sampled from two of the investigated catchments, DMH-0128 and OF-0078, contained concentrations of ammonia, surfactants, and chlorine above MS4 General Permit (Permit) potential illicit discharge threshold criteria. Potential Illicit Discharge Parameter(s) Below Permit Threshold Criteria •Drainage infrastructure within nine investigated catchments contained concentrations of illicit discharge parameters (ammonia, chlorine, and/or surfactants) detected in flow below combined Permit threshold criteria. These detections do not require additional investigation under the Permit requirements. However, the Town may want to periodically revisit areas with detections above individual Permit threshold criteria during dry weather conditions to verify whether potential sewage or non-stormwater related discharges are present. No Potential Illicit Discharges •Drainage infrastructure within the seventeen remaining investigated catchments contained no concentrations of illicit discharge parameters (ammonia, chlorine, and/or surfactants) above the Permit threshold criteria. No further investigation of these catchments is required except where noted. Lexington, MA (0227871.17) 2 Woodard & Curran, Inc. Lexington, MA MS4 PY6 Catchment Investigation Memo July 2024 Additional Recommendations It is recommended that the Town: •Investigate all instances where structures were unable to be located in the field or were found to deviate from existing mapping. If investigation results in significant alterations to mapping, further IDDE investigation may be required. •Maintain all infrastructure found to contain standing water. Catchment investigation prioritizations have been updated based on the information provided in this memorandum. Additional illicit discharge detection and elimination (IDDE) activities should be conducted in the two catchments with potential illicit discharges that are listed above to identify and mitigate non-stormwater discharges to the Town’s drainage system, if present, per the recommendations presented in this memorandum. Refer to Attachment B and Attachment C for specific locations where investigation and/or maintenance is recommended. PURPOSE AND BACKGROUND This memorandum describes the results of IDDE investigations performed in the Town of Lexington, MA (Town) during Permit Year (PY) 6 within twenty-eight catchments. This memorandum is intended to fulfill Permit Part 2.3.4.8.c.iii, which requires all data collected as part of catchment investigations to be recorded and reported annually. Dry weather outfall screening and sampling results obtained for the Town’s outfalls screened during previous IDDE investigations were initially used to prioritize the order of catchment investigations. Catchments where potential illicit discharge indicators were detected above individual Permit threshold criteria in dry weather flow collected from outfalls were assigned an elevated prioritized for future investigation. The remaining catchments were assigned a low priority for investigation due to no observed dry weather flow or no detections of potential illicit discharge parameters in sampled flow. Drainage infrastructure within the following twenty-eight catchments was investigated during the period discussed in this memorandum: •DMH-01281 •OF-0077 •OF-0394 •DMH-1045 •OF-00781 •OF-0399 •OF-0032 •OF-0080 •OF-0400 •OF-0034 •OF-0114 •OF-0401 •OF-0036 •OF-0188 •OF-0402 •OF-0046 •OF-0287 •OF-0403 •OF-0054 •OF-0327 •OF-0435 •OF-0056 •OF-0362 •OF-0437 •OF-0057 •OF-0363 •OF-0059 •OF-0382 Notes: 1. Additional investigations are required to determine source(s) of potential illicit discharge(s). Lexington, MA (0227871.17) 3 Woodard & Curran, Inc. Lexington, MA MS4 PY6 Catchment Investigation Memo July 2024 IDDE INVESTIGATION METHODOLOGY Between July 2023 and October 2023, SDE, Inc. performed catchment investigations following the methodology in Permit Part 2.3.4.8.c.ii.1.c-d (Catchment Investigations) and the Town’s IDDE Program Manual. Drain manholes, and in some cases, catch basins were opened and visually inspected to determine the presence or absence of dry weather flow and visible and/or olfactory indicators of sewage. Where flow was observed, samples were collected and screened for potential illicit discharge indicators using field test kits. Select samples were also submitted for laboratory ammonia analysis. General observations related to infrastructure condition were also recorded when structures were accessed as presented in Attachment C. In general, drainage infrastructure was investigated throughout the drainage network starting upstream and working downstream (outfall) to understand the relationship between potential upstream contamination on downstream water quality. Where field test kits detected concentrations of potential illicit discharge parameters above Permit threshold criteria in dry weather flow, nearby infrastructure was accessed and screened to bracket the source of potential illicit discharges for future investigations. Building and/or infrastructure dye tests were not performed during this round of catchment investigations. Generally, dye testing is used in some locations where visual evidence of sewer impacts or potential illicit discharges is identified in drainage infrastructure once the extent of impacts have been bracketed. During the dye test non-toxic dye is introduced to either plumbed fixtures within building(s) or sanitary sewer manholes adjacent to identified impacted drainage infrastructure to determine whether dye is visible in the drainage infrastructure. Information obtained during catchment investigation activities was recorded in ESRI’s ArcGIS Field Maps application. This information is available in the geographic information system (GIS) setup by Woodard & Curran and shared with the Town. DRY WEATHER SCREENING DATA EVALUATION CRITERIA Permit Part 2.3.4.8.c.ii.1.c-d requires drainage infrastructure investigations during dry weather flow. Where dry weather flow is present, it is typically sampled using field test kits for the presence of ammonia, surfactants, and chlorine. In some cases, dry weather flow is sampled for bacteria; however, this is not required during catchment investigations and no bacteria samples were collected during the catchment investigations described in this memorandum. In accordance with the MS4 General Permit, flow is considered likely to contain illicit discharges from sanitary sources if dry weather screening indicates: •Olfactory or visual evidence of sewage; •Ammonia ≥0.5 parts per million (ppm), surfactants ≥0.25 ppm, and bacteria ≥ water quality standards; or •Ammonia ≥0.5 ppm, surfactants ≥0.25 ppm, and detectable chlorine. Lexington, MA (0227871.17) 4 Woodard & Curran, Inc. Lexington, MA MS4 PY6 Catchment Investigation Memo July 2024 Dry weather sample screening results obtained during catchment infrastructure investigations were compared against these criteria to determine the potential presence of illicit discharges. In addition, test kit results where ammonia, surfactants and/or chlorine are detected above their individual Permit threshold criteria but below the combined Permit criteria for potential illicit discharges can be potential indicators of other illicit discharges, such as swimming pool dewatering discharges, vehicle/equipment wash waters, incorrectly connected washing machine laterals, or diluted flow from sewer-related sources. These types of potential illicit discharge indicators are not typically regulatory drivers for additional investigations, but investigations may be warranted depending on a variety of factors such as the proximity of the corresponding drainage pipe(s) to identified potential illicit discharges, the location of the catchment outfall in relation to sensitive receptors, and other community-specific factors. This data and the infrastructure should be reviewed on a case-by- case basis to determine whether non-Permit drivers are present that would warrant further investigation. CATCHMENT INVESTIGATION RESULTS An evaluation of the dry weather flow screening results identified potential sewer-related illicit discharges to drainage infrastructure in two of the twenty-eight investigated catchments. In general, potential illicit discharges were isolated to specific drainage pipe segments, as shown on the figures in Attachment A. A summary of the drainage system infrastructure investigation findings is provided in Table 1, below. Note that “complete” drainage system infrastructure investigation statuses refer to investigation of the Town-owned drainage infrastructure located within the system and not the confirmation of location and removal of illicit discharges that may be present in sanitary sewer or private infrastructure discharging to the MS4. TABLE 1: SUMMARY OF CATCHMENT INVESTIGATION RESULTS Catchment ID Drainage System Infrastructure Investigation Status Notes Potential Illicit Discharge(s) Detected DMH-0128 Complete1 Ammonia, surfactants, and chlorine detected in one drainage pipe segment. Additional source investigations are required. OF-0078 Complete1 Ammonia, surfactants and chlorine detected in one drainage pipe segment. The pipe was subsequently re-investigated and was observed with standing water. The initial inspection indicating potential illicit discharge should be further investigated. Additional source investigations are required. Catchments with Potential Illicit Discharge Parameter(s) Detected Below Permit Threshold Criteria OF-0046 Partial4 Chlorine detected in two drainage pipe segments above Permit individual threshold criteria. OF-0057 Complete3 Ammonia and surfactants detected in one drainage pipe segment above Permit individual threshold criteria. Lexington, MA (0227871.17) 5 Woodard & Curran, Inc. Lexington, MA MS4 PY6 Catchment Investigation Memo July 2024 Catchment ID Drainage System Infrastructure Investigation Status Notes Catchments with Potential Illicit Discharge Parameter(s) Detected Below Permit Threshold Criteria OF-0077 Partial 2, 4 Chlorine detected in one drainage pipe segment abovePermit individual threshold criteria. OF-0080 Complete3 Chlorine detected in one drainage pipe segment above Permit individual threshold criteria. OF-0114 Partial4 Chlorine detected in one drainage pipe segment above Permit individual threshold criteria. OF-0188 Complete3 Surfactants and/or chlorine detected in four drainage pipe segments above Permit individual threshold criteria. OF-0363 Complete3 Surfactants detected in one drainage pipe segment above Permit individual threshold criteria. OF-0400 Complete3 Surfactants and/ or chlorine detected in two drainage pipe segments above Permit individual threshold criteria. OF-0437 Complete3 Chlorine detected in four drainage pipe segments above Permit individual threshold criteria. Catchments with No Potential Illicit Discharges Detected DMH-10456 OF-00325 OF-00345 OF-00365 OF-00544 OF-00565 OF-00594 OF-02874 OF-03275 OF-03625,7 OF-03824 OF-03945 OF-03995 OF-04015 OF-04025 OF-04035 OF-04354 -- Notes: 1. Additional investigations are required to determine source(s) of potential illicit discharge(s). 2. Additional mapping is required to determine pipe configurations. 3. Pipe segments have been substantially investigated and no further catchment investigations are required. Some pipe segments contain concentrations of potential illicit discharge parameters below Permit criteria. 4. Additional catchment investigations are required to complete drainage pipe investigations. 5. Pipe segments have been substantially investigated and no further catchment investigations are required. 6. Pipe segments investigated during PY6 investigations were cleared, but pipes with positive test kits were found during previous investigations. 7. All pipe segments in this catchment contain either standing water or are partially inspected. Maintenance should be conducted. A table summarizing screening results obtained during catchment investigations is provided in Attachment B, and a table summarizing surficial drainage infrastructure noted during catchment investigations is provided in Attachment C. CONCLUSIONS AND RECOMMENDATIONS Catchments with Identified Potential Illicit Discharges Potential illicit discharges have been identified in flow sampled from drainage infrastructure in the following catchments, which will require additional investigation to determine the source(s) Lexington, MA (0227871.17) 6 Woodard & Curran, Inc. Lexington, MA MS4 PY6 Catchment Investigation Memo July 2024 of identified indicator parameters: DMH-0128 and OF-0078. Specific recommendations regarding these catchments are provided below. DMH-0128 Ammonia, surfactants, and chlorine were detected above potential illicit discharge criteria in dry weather flow collected from the northeast inlet of DMH-0018 (DGM-0447) at Lexington High School on Waltham Street. During prior investigations conducted in 2019, pipe segment DGM-0450, which is immediately upstream of pipe segment DGM-0447, could not be located. There were no inlets observed in DMH-0021 during this initial investigation indicating that DMH-0021 is the drain starter. The issue here appears to originate in DGM-0047. Typically, the recommendation for this scenario would be dye testing the adjacent infrastructure. Given that the adjacent building is the Lexington High School, additional laboratory sampling (E. coli, surfactants, total and human Bacteroides) should be conducted to verify the contamination. If follow up sampling indicates a potential illicit discharge then dye testing will be recommended. OF-0078 Ammonia, surfactants, and chlorine were detected above potential illicit discharge criteria in dry weather flow collected from the northeast inlet of DMH-0871 (DGM-2945) at the intersection of Fairlawn Lane and Fiske Road. This pipe segment was later revisited and standing water was observed. DGM-2945 should be returned to determine if the pipe contains flow or standing water. The pipe segment directly upstream (DGM-2943) of DGM-2945 on Fairlawn Lane was cleared indicating that the contamination likely originates in DGM-2945. However, the standing water present during the second inspection makes it difficult to verify that for certain. It is recommended the Town removes standing water in this pipe in order to bracket the source of contamination. If the Town is unable to remove standing water upstream, dye testing of the adjacent buildings area should be complete. Catchments with Non-Stormwater Parameters Below Combined Permit Threshold Criteria Dry weather flow sampled from drainage infrastructure in the nine catchments listed in Table 1 contained concentrations of one or more illicit discharge indicator parameters above individual Permit threshold criteria but below the combined Permit threshold criteria for potential illicit discharges. Although these detections do not require additional catchment investigation under the Permit, the Town may consider investigating these locations in the future once investigations are completed in higher priority catchments. In some cases, detection of individual illicit discharge criteria can indicate a dilute source of an illicit discharge in the vicinity. Catchments Cleared of Potential Illicit Discharges Drainage infrastructure has been substantially investigated and no potential illicit discharges or positive test kit detections have been identified in the 17 catchments listed in Table 1. No further catchment investigations are recommended in these catchments. Lexington, MA (0227871.17) 7 Woodard & Curran, Inc. Lexington, MA MS4 PY6 Catchment Investigation Memo July 2024 Partial drainage infrastructure investigations have been conducted in the five catchments listed in Table 1 with no potential illicit discharges identified. Catchment investigations will resume in these catchments during future field efforts. MAINTENANCE AND MAPPING RECOMMENDATIONS Standing water was observed in pipe segments within several catchments, as depicted on figures in Attachment A and in the summary tables in Attachment B and Attachment C. Locations where standing water have been identified should be maintained and/or evaluated to determine and abate the cause to promote adequate drainage through the catchment. After maintenance has been completed, these catchments should be revisited to attempt to complete catchment investigations. Additionally, drainage infrastructure within some catchments appears to be incompletely mapped, as noted in Table 1. These catchments may require further investigation if new structures are identified that have not been representatively inspected during the investigations summarized in this memorandum. GENERAL RECOMMENDATIONS Additional IDDE activities should be conducted in the catchments with potential illicit discharges that are listed above to identify and mitigate non-stormwater discharges to the Town’s drainage system. Verified illicit discharges should be addressed in accordance with the Town’s IDDE Program Manual and applicable regulations. Upon remediation of an illicit discharge, the associated outfall should be rescreened within one year during dry weather to verify no potential illicit discharge indicators at the catchment discharge point. Lexington, MA (0227871.17) Woodard & Curran, Inc. Lexington, MA MS4 PY6 Catchment Investigation Memo July 2024 ATTACHMENT A: CATCHMENT INVESTIGATION FIGURES CB-0013 CB-0454 CB-0453 CB-7799 CB-0016 CB-0020 CB-7834 CB-7688 CB-7690 CB-7695 CB-0024 CB-0305 CB-0240 CB-0250 CB-0256 CB-0272 CB-0258 CB-0266 CB-0265 CB-0263 CB-0268 CB-0248 CB-0452 CB-7893 CB-0465 CB-0501 CB-0503 CB-7693 CB-0499 CB-7867 CB-0245 CB-0244 CB-0236 CB-0231 CB-7837 CB-0225 CB-7691 CB-0233 CB-0485 CB-7705 CB-0023 CB-0021 CB-0508 CB-0514 CB-0505 CB-0436 CB-0429 CB-0014 CB-0422 CB-0510 CB-0511 CB-0469 CB-0431 CB-0435 CB-0275 CB-0440 CB-0433 CB-0442 CB-0428 CB-0438 CB-0495 CB-0026 CB-0015 CB-7710 CB-0496 CB-0420 CB-0460 CB-7689CB-7692 CB-7694 CB-0237 CB-0229 CB-0441 CB-0512 CB-0466 CB-0504 CB-0267 CB-0269 CB-0421 CB-0018 CB-0439 CB-0513 CB-0278 CB-0493 CB-7568 CB-0235 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT DMH-0128 0 330165 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole CB-0193CB-0316 CB-4056 CB-4052 CB-4057 CB-0194 CB-0195 CB-0395 CB-4047 CB-4059 CB-0197 CB-4035 CB-4040 CB-4050 CB-4054 CB-4058 CB-4034 CB-4025 CB-7552 CB-0360 CB-0358 CB-4048 CB-4038 CB-7550 CB-4029 CB-4046 CB-7548 CB-0396 CB-4028 CB-4036 CB-4037 CB-4032 CB-4041 CB-4043 CB-4026 CB-4027 CB-4042 CB-7553 CB-4030 CB-4049 CB-7554 CB-7808 Culvert ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT DMH-1045 0 310155 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole DMH-0206 DMH-0509 DMH-0510 DMH-0511 DMH-0513 DMH-0515 CB-0673 CB-1630 CB-1743 CB-1635 CB-7378 CB-1629 CB-1744 CB-1636 CB-1626 CB-7417 CB-1745 CB-1628 CB-7852 CB-1634 OF-0032 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0032 0 13065 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole CB-7282 CB-0405 CB-0414 CB-0404 CB-7285 CB-1653 CB-1649 CB-1652 CB-1666 CB-1663 CB-1650 CB-7427 CB-7281 CB-0413 CB-1641 CB-1665 CB-7437 CB-0408 CB-7438 CB-7287 CB-7289 CB-0406 CB-1637 CB-1638 CB-1664 CB-0411 CB-7286 CB-1671 CB-0407 CB-1647 CB-1667 CB-1669 CB-1668 CB-0412 CB-1639 CB-1648OF-0034 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0034 0 300150 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole DMH-0519 DMH-0528 DMH-0530 CB-1659 CB-1660 CB-1685 CB-7944 CB-1673 CB-1683 CB-1678 CB-1661 CB-1679 CB-1681 OF-0036 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0036 0 11055 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole CB-1914 CB-1982 CB-2272 CB-7382 CB-2267 CB-2303CB-7385 CB-7387 CB-1972 CB-7746 CB-7949 CB-7951 CB-7384 CB-2005 CB-1996 CB-2004 CB-2310 CB-2319 CB-1881 CB-8067 CB-8069 CB-1913 CB-2008 CB-1999 CB-1968 CB-1909 CB-2301 CB-1987 CB-2293 CB-1989 CB-1883 CB-2300 CB-2294 CB-1981 CB-1983 CB-2010 CB-1910 CB-2297 CB-1975 CB-1907 CB-2269 CB-7379 CB-1912 CB-2296 CB-1971 CB-2009 CB-1969 CB-1988 OF-0046 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0046 0 310155 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole DMH-0646 DMH-0647 DMH-0648 DMH-0649 DMH-0658 DMH-0659 DMH-0660 CB-2118 CB-2089 CB-2121 CB-2078 CB-8074 CB-8075 CB-7980 CB-2131 CB-2088 CB-2127 CB-2085 CB-2117 CB-2130 CB-2120 CB-2132 CB-2091 CB-2122 CB-2128CB-2083 CB-2119 CB-2080 OF-0054 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0054 0 210105 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole DMH-0655 DMH-0656 DMH-0657 DMH-0661 DMH-0662 DMH-0664 DMH-0665 DMH-1998 DMH-1999 DMH-2000 CB-2140 CB-2136 CB-2134 CB-2123 CB-2141 CB-2143 CB-2137 CB-2125 CB-2149 CB-2193 CB-8073 CB-7743 CB-2124 CB-2135 CB-2146 CB-2114 CB-2109 CB-2145 CB-2142 CB-2110 CB-2138 CB-2139 CB-2112 CB-2111 Unknown OF-0056 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0056 0 16080 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole CB-7587 CB-2151 CB-2703 CB-2155 CB-2199 CB-2149 CB-2691 CB-2688 CB-2144 CB-2175 CB-2169 CB-2206 CB-2694 CB-2191 CB-2173 CB-2146 CB-2188 CB-2156 CB-2160 CB-2696 CB-2153 CB-2171 CB-3124 CB-2198 CB-2159 CB-2152 CB-2176 OF-0057 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0057 0 360180 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole CB-2140 CB-3030 CB-7587 CB-2151 CB-7740 CB-3099 CB-3098 CB-3108 CB-2703 CB-2155 CB-2195 CB-2143 CB-3032 CB-2704 CB-3033 CB-2149 CB-2691 CB-2693 CB-2688 CB-2144 CB-2175 CB-2169 CB-2162 CB-3106CB-3103 CB-2173 CB-2196 CB-2146 CB-2163 CB-3100 CB-2167 CB-2156 CB-2160 CB-2696 CB-2153 CB-2164 CB-3135 CB-2171 CB-7734 CB-3124 CB-2170 CB-2708 CB-2159 CB-2139 CB-3028 CB-3111 CB-7598 Unknown Culvert OF-0078 OF-0057 OF-0059 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0059 0 380190 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole CB-7587 CB-2151 CB-2703 CB-2155 CB-2199 CB-2149 CB-2691 CB-2688 CB-2144 CB-2175 CB-2169 CB-2206 CB-2694 CB-2191 CB-2173 CB-2146 CB-2188 CB-2156 CB-2160 CB-2696 CB-2153 CB-2171 CB-3124 CB-2198 CB-2159 CB-2152 CB-2176 OF-0057 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0077 0 360180 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole OF-0078 OF-0057 OF-0059 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0078 0 630315 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole DMH-0845 DMH-0849 DMH-0850 DMH-0851 DMH-0852 DMH-1753 DMH-1754 CB-3064 CB-3039 CB-3042 CB-3057 CB-0690 CB-3048 CB-0686 CB-0691 CB-3063 CB-3043 CB-3040CB-3045 CB-3065 CB-3068 CB-3046 CB-3067 CB-3044 CB-3058 CB-3066 CB-3062 CB-3059 CB-3060 Unknown Culvert OF-0080 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0080 0 200100 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole CB-0887 CB-3269 CB-3783 CB-3729 CB-7744 CB-0884 CB-0885 CB-3672 CB-3706 CB-0924 CB-3777 CB-3778 CB-3792 CB-7754 CB-7753 CB-3715 CB-3725 CB-3737 CB-3733 CB-7878 CB-0888 CB-0893 CB-0909 CB-3779 CB-0902 CB-0620 CB-3719 CB-3704 CB-3697 CB-3698 CB-3727 CB-3673 CB-0905 CB-0906 CB-3274 CB-3722 CB-3776 CB-3273 CB-3750 CB-3711 CB-3713 CB-3784 CB-3721 CB-0904 CB-0890 CB-3710 CB-3731 CB-3716 CB-3781 CB-3712 CB-3692 CB-3691 CB-3693 CB-3694 CB-0908 CB-3709 CB-3708 CB-3696 CB-3700 CB-3271 OF-0114 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0114 0 420210 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole Headwall Headwall Headwall OF-0188 OF-0146 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0188 0 520260 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole CB-1897 CB-1899 CB-2054 CB-2058 CB-2057 CB-2063 CB-2059 CB-2043 CB-2133 CB-2073 CB-2066 CB-2071 CB-2062 CB-1929 CB-2078 CB-2035 CB-2069 CB-2040 CB-7980 CB-1920 CB-1926 CB-2214 CB-7741 CB-7137 CB-1924 CB-2088 CB-2075 CB-2055 CB-2103 CB-1932 CB-2222 CB-2215 CB-1921 CB-2039 CB-2051 CB-1931 CB-2045 CB-2065 CB-2101 CB-2048 CB-2047 CB-7745 CB-2042 CB-2046 CB-2108 CB-1928 CB-1896 CB-2072 CB-2061 CB-2104 CB-2038 CB-2037 CB-2105 CB-2056 CB-1898 CB-2080 CB-2068 CB-1901 CB-7850 CB-1927 Unknown OF-0287 OF-0382OF-0382 OF-0394 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0287 0 310155 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole DMH-0827 DMH-1945 DMH-0825 DMH-0824 DMH-0826 CB-2902 CB-2907 CB-2908 CB-2900 CB-3023 CB-2904 CB-2650 CB-2649 CB-2901 CB-2906 CB-2903 CB-2905 OF-0327 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0327 0 12060 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole DMH-1452 CB-5674 CB-5673 CB-5675 CB-5672 Headwall OF-0362 OF-0363 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0362 0 14070 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole DMH-1452 DMH-1453 DMH-1454 DMH-1455 DMH-1458 DMH-1459 CB-5676 CB-5674 CB-5689 CB-5678 CB-5673 CB-5681 CB-5688 CB-5680 CB-7187 CB-5675 CB-5691 CB-5690 Headwall Headwall OF-0362 OF-0363 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0363 0 210105 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole DMH-0643 DMH-0644 DMH-0645 DMH-0646 DMH-0650 DMH-0653DMH-0654 DMH-0652 DMH-0627DMH-0627DMH-0627DMH-0628DMH-0629DMH-0629 DMH-0630 DMH-0631 DMH-0632 DMH-0633 DMH-0634 DMH-0635 DMH-0637 DMH-0638 DMH-0639 DMH-0640 DMH-0641 DMH-0642 DMH-1749 DMH-1750 DMH-1751 DMH-1752 CB-2218 CB-2054 CB-2058 CB-2057 CB-2063 CB-2098 CB-2059 CB-2043 CB-2133 CB-2073 CB-2066 CB-2071 CB-2062 CB-7327 CB-2078 CB-2069 CB-2040 CB-7980 CB-7985 CB-7989 CB-2092 CB-2214 CB-7741 CB-7137 CB-1924 CB-2044 CB-2088 CB-2075 CB-2055 CB-2215 CB-1921 CB-2051 CB-2045 CB-2065 CB-2100 CB-2048 CB-2047 CB-2219 CB-7745 CB-2046 CB-2072 CB-2061 CB-2105 CB-2056 CB-2068 OF-0287 OF-0382OF-0382 OF-0394 ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0382 0 275137.5 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole OF-0394 DMH-0633 DMH-0634 DMH-0635 DMH-0639 DMH-0640 DMH-1749 DMH-1750 DMH-1751 DMH-1752 CB-2218 CB-2059 CB-2214 CB-2055 CB-2215 CB-2220 CB-2216 CB-2219 CB-2061 CB-2049 CB-2056 CB-2223 CB-2068 CB-2213 Unknown ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0394 0 250125 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole OF-0401 OF-0399 DMH-1757 DMH-1758 DMH-1762 DMH-1763 CB-0700 CB-0714 CB-0699 CB-0713 CB-0711 CB-0712 Culvert Culvert ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0399 0 12060 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole OF-0400 OF-0401 OF-0399 DMH-1758 DMH-1759 DMH-1760 DMH-1761 DMH-1762 DMH-1763 DMH-1776 DMH-1777 DMH-1778 CB-0700 CB-0736 CB-0742 CB-0735 CB-0737 CB-0699 CB-0709 CB-0753 CB-0741 CB-0702 CB-0740 CB-0743 CB-0739 CB-0710 CB-0711 CB-0701 CB-0712 Culvert Culvert ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0400 0 18090 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole OF-0401 OF-0399 DMH-0217 DMH-1758 DMH-1763 DMH-1764DMH-1765 DMH-1766 DMH-1767 DMH-1768 DMH-1776 DMH-1777 CB-0704 CB-0706 CB-0700 CB-0707 CB-0660 CB-0703 CB-0736 CB-0735 CB-0699 CB-0702 CB-0708 CB-0705 CB-0749 CB-0701 CB-0750 Culvert ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0401 0 280140 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole OF-0402 OF-0403 DMH-1766 DMH-1767 DMH-1768 DMH-1769 DMH-1770 DMH-1771 DMH-1772 DMH-1773 DMH-1774 DMH-1775 DMH-1776 DMH-1777 DMH-1779 CB-0706 CB-0707 CB-0738 CB-0731 CB-0733 CB-0767 CB-0768 CB-0734 CB-0730 CB-0732 CB-0736 CB-0729 CB-0735 CB-0737 CB-0728 CB-0708 CB-0705 CB-0749 CB-0727 CB-0748 CB-0747 CB-0750 Culvert ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0402 0 320160 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole OF-0400 OF-0403 DMH-1759 DMH-1760 DMH-1761 DMH-1762 DMH-1771 DMH-1772 DMH-1773 DMH-1774 DMH-1775 DMH-1776 DMH-1777 DMH-1778 CB-0738 CB-0731 CB-0733 CB-0734 CB-0730 CB-0732 CB-0736 CB-0742 CB-0729 CB-0735 CB-0737 CB-0709 CB-0753 CB-0728 CB-0741 CB-0740 CB-0743 CB-0739 CB-0727 CB-0710 CB-0711 Culvert Culvert ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0403 0 230115 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole OF-0437 OF-0435 CB-5763 CB-5683 CB-5684 CB-5715 CB-5701 CB-5706 CB-7702 CB-5728 CB-5727 CB-5781 CB-5783 CB-5741 CB-7330 CB-5725 CB-5738 CB-7329 CB-5731 CB-5678 CB-5686 CB-5767 CB-5732 CB-5745 CB-5740 CB-5687 CB-5734 CB-5744 CB-5685 CB-5681 CB-7703 CB-5723 CB-5717 CB-7187 CB-5784 CB-5704 CB-5691 CB-5721 CB-5702 CB-7571 CB-5697 CB-5719 CB-5720 CB-7572 CB-5698 CB-5692 CB-5700 CB-5710 CB-5714 CB-5708 CB-5712 CB-5709 Headwall ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0435 0 500250 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole OF-0437 OF-0362 OF-0435 OF-0363 DMH-1452 DMH-1453 DMH-1454 DMH-1455 DMH-1456 DMH-1457 DMH-1458 DMH-1459 DMH-1460 DMH-1461 DMH-1462 DMH-2044 CB-5676 CB-5683 CB-5684 CB-5701 CB-5674 CB-5689 CB-5678 CB-5673 CB-5686 CB-5687 CB-5685 CB-5681 CB-7186 CB-5688 CB-5680 CB-7187 CB-5691 CB-5690 CB-7572 CB-5698 CB-7573 CB-5692 Headwall Headwall ¯ Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources: Town of Lexington, ESRI, Woodard & Curran, MassGIS, 2024. Town of Lexington, MA PERMIT YEAR 6 IDDE INVESTIGATIONS CATCHMENT OF-0437 0 370185 Feet Map Created: JULY 2024 Stormwater Assets Not Tested Planned No Fixtures Legal No Dye Observed Corrected Dye in SMH & DMH Not Legal Building Dye Testing Not Yet Inspected Standing Water Partial Inspection Cleared UpstreamContamination Positive Test SuspectedIllicit Discharge Visual Evidence ofIllicit Discharge IDDE Pipe Inspections byIllicit Discharge StatusOutfall LegendCatch Basin Inspections Inspected Catch Basin Catch Basin Manhole Inspections Inspected Manhole Manhole Lexington, MA (0227871.17) Woodard & Curran, Inc. Lexington, MA MS4 PY6 Catchment Investigation Memo July 2024 ATTACHMENT B: CATCHMENT INVESTIGATION SCREENING RESULTS Attachment B: Catchment Investigation Screening Results MS4 General Permit Illicit Discharge Detection and Elimination Program Permit Years 6 Catchment Investigation Summaries Lexington, MA Infrastructure ID Inspection Date Pipe ID Standing Water Flow Flow Color Velocity Ammonia (ppm)Surfactants (ppm)Chlorine (ppm)Comments ≥0.5 ppm1 ≥0.25 ppm1 ≥0.02 ppm2 DMH-0128 DMH-0018 10/3/2023 DGM-0447 No Yes Orange Slow 0-0.5 ft/sec 0.5 1.5 1.35 Laboratory samples collected for ammonia. Ammonia - 1.92 mg/L. CB-4049 10/3/2023 DGM-7502 No Yes Colorless Medium 0.5-1.75 ft/sec <0.05 <0.125 <0.02 DMH-0515 8/3/2023 DGM-1616 Yes No N/A N/A ------ Pipe is mapped as extending from DMH-0513 to DMH-0515. In the field, this is two discrete pipes. This pipe inspection is for CB-1635: DMH-0515.OF-0032 8/1/2023 DGM-1620 Yes No N/A N/A ------ CB-1635 8/1/2023 DGM-1616 No No N/A N/A ------ Pipe is mapped as extending from DMH-0513 to DMH-0515. In the field, this is two discrete pipes. This pipe inspection is for DMH-0513:CB-1635. OF-0034 9/5/2023 DGM-1653 Unknown Unknown N/A N/A ------Unable to access outfall. CB-1667 9/5/2023 DGM-1652 No Yes Colorless Medium 0.5-1.75 ft/sec <0.05 <0.125 <0.02 OF-0036 8/1/2023 DGM-1670 No No N/A N/A ------ CB-1975 9/5/2023 DGM-1987 No No N/A N/A ------ CB-1969 9/5/2023 DGM-1999 No No N/A N/A ------ CB-1967 8/21/2023 DGM-2001 Yes No N/A N/A ------ CB-1967 8/21/2023 DGM-1994 No Yes Colorless Medium 0.5-1.75 ft/sec 0.2 <0.125 0.24 CB-1969 8/21/2023 DGM-8723 No No N/A N/A ------ CB-1973 8/21/2023 DGM-8720 No No N/A N/A ------ CB-1973 8/21/2023 DGM-1989 Yes No N/A N/A ------ CB-1973 8/21/2023 DGM-1992 No Yes Colorless Medium 0.5-1.75 ft/sec 0.3 <0.125 0.11 CB-1973 8/21/2023 DGM-8721 No No N/A N/A ------ CB-1975 8/21/2023 DGM-1988 No No N/A N/A ------ OF-0046 8/21/2023 DGM-2008 No Yes Colorless Medium 0.5-1.75 ft/sec <0.05 <0.125 <0.02 CB-8074 7/25/2023 DGM-2107 No No N/A N/A ------ CB-8074 7/25/2023 DGM-2098 No No N/A N/A ------ OF-0056 7/25/2023 DGM-2157 No No N/A N/A ------ CB-2154 10/3/2023 DGM-2180 No No N/A N/A ------ CB-2157 10/3/2023 DGM-2174 No No N/A N/A ------ CB-2151 10/3/2023 DGM-2176 Yes No N/A N/A ------ CB-2151 10/3/2023 DGM-2170 No No N/A N/A ------ OF-0057 10/3/2023 DGM-2172 No Yes Colorless Fast 1.75 ft/sec or Greater 1 0.5 <0.02 CB-2162 9/5/2023 DGM-2191 Yes No N/A N/A ------ CB-2167 9/5/2023 DGM-2190 No No N/A N/A ------ CB-2167 9/5/2023 DGM-2187 Yes No N/A N/A ------ OF-0059 8/21/2023 DGM-2193 Yes No N/A N/A ------ OF-0032 OF-0034 OF-0036 OF-0046 Single Sample Threshold Levels DMH-1045 OF-0054 OF-0056 OF-0057 OF-0059 Lexington, MA (0227871.17) Attach B - CI Results Page 1 of 4 Woodard Curran, Inc. June 2024 Attachment B: Catchment Investigation Screening Results MS4 General Permit Illicit Discharge Detection and Elimination Program Permit Years 6 Catchment Investigation Summaries Lexington, MA Infrastructure ID Inspection Date Pipe ID Standing Water Flow Flow Color Velocity Ammonia (ppm)Surfactants (ppm)Chlorine (ppm)Comments CB-2949 8/1/2023 DGM-2761 No Yes Colorless Unknown 0.4 <0.125 0.4 CB-2950 8/1/2023 DGM-2763 Yes No N/A N/A ------CB-2950 8/1/2023 DGM-2762 Yes No N/A N/A ------ OF-0077 8/1/2023 DGM-2765 Unknown Unknown N/A N/A ------Could not locate. OF-0077 8/1/2023 DGM-2766 Unknown Unknown N/A N/A ------Could not locate. CB-2948 8/1/2023 DGM-8709 Yes No N/A N/A ------ DMH-2066 10/3/2023 DGM-2924 N/A N/A N/A N/A ------DMH-2066 10/3/2023 DGM-7483 Yes No N/A N/A ------ DMH-0843 10/3/2023 DGM-2817 No Yes Colorless Medium 0.5-1.75 ft/sec 0.1 0.5 0.3DMH-0781 10/3/2023 DGM-2570 No Yes Colorless Medium 0.5-1.75 ft/sec <0.05 0.75 <0.02 CB-3162 10/3/2023 DGM-2941 No No N/A N/A ------CB-3160 10/3/2023 DGM-2943 No No N/A N/A ------ DMH-0871 9/5/2023 DGM-8711 No No N/A N/A ------DMH-0871 9/5/2023 DGM-2939 Yes No N/A N/A ------ DMH-0787 9/5/2023 DGM-2583 No No N/A N/A ------ DMH-0871 9/5/2023 DGM-2945 Yes No N/A N/A ------ This pipe was inspected twice. On 8/29/2023 it was flowing and flow met the likely sewer indicator threshold. On 9/5/2023 the manhole was revisited and this pipe was observed with standing water. CB-3144 9/5/2023 DGM-2973 No No N/A N/A ------DMH-0784 9/5/2023 DGM-8140 No No N/A N/A ------ DMH-0784 9/5/2023 DGM-2600 No No N/A N/A ------CB-3171 9/5/2023 DGM-2932 No No N/A N/A ------ DMH-0784 9/5/2023 DGM-2598 No No N/A N/A ------DMH-0787 8/29/2023 DGM-2588 No Yes Colorless Slow 0-0.5 ft/sec 0.3 <0.125 0.2 CB-3187 8/29/2023 DGM-7267 No Yes Colorless Slow 0-0.5 ft/sec <0.05 <0.125 <0.02CB-3149 8/29/2023 DGM-2968 No Yes Colorless Slow 0-0.5 ft/sec <0.05 <0.125 0.21 DMH-0871 8/29/2023 DGM-2945 No Yes Colorless Slow 0-0.5 ft/sec 10 0.5 0.53 This pipe was inspected twice. On 8/29/2023 it was flowing and flow met the likely sewer indicator threshold. On 9/5/2023 the manhole was revisited and this pipe was observed with standing water. CB-3138 8/29/2023 DGM-2980 No Yes Colorless Medium 0.5-1.75 ft/sec <0.05 <0.125 0.1 CB-3149 8/29/2023 DGM-2966 No Yes Colorless Medium 0.5-1.75 ft/sec 0.2 <0.125 0.15 CB-3144 8/29/2023 DGM-2972 No Yes Colorless Fast 1.75 ft/sec or Greater 0.3 0.25 0.11 OF-0078 9/5/2023 DGM-2820 No Yes Colorless Medium 0.5-1.75 ft/sec 0.1 <0.125 0.26 CB-3138 8/29/2023 DGM-2959 No Yes Colorless Medium 0.5-1.75 ft/sec <0.05 <0.125 0.35 OF-0080 9/5/2023 DGM-2828 No Yes Colorless Medium 0.5-1.75 ft/sec 0.3 <0.125 0.32 DMH-0992 8/3/2023 DGM-8673 No Yes Colorless Slow 0-0.5 ft/sec <0.05 <0.125 0.1 OF-0114 8/3/2023 DGM-3417 No Yes Yellow Slow 0-0.5 ft/sec <0.05 <0.125 <0.02 CB-3729 8/1/2023 DGM-3428 No Yes Colorless Unknown <0.05 <0.125 <0.02 OF-0114 8/1/2023 DGM-7342 Unknown Unknown N/A N/A ------Could not locate. DMH-0992 8/1/2023 DGM-3406 No No N/A N/A ------ CB-3715 8/1/2023 DGM-8136 Yes No N/A N/A ------ CB-3712 8/1/2023 DGM-3408 No No N/A N/A ------ OF-0078 OF-0077 OF-0080 OF-0114 Lexington, MA (0227871.17) Attach B - CI Results Page 2 of 4 Woodard Curran, Inc. June 2024 Attachment B: Catchment Investigation Screening Results MS4 General Permit Illicit Discharge Detection and Elimination Program Permit Years 6 Catchment Investigation Summaries Lexington, MA Infrastructure ID Inspection Date Pipe ID Standing Water Flow Flow Color Velocity Ammonia (ppm)Surfactants (ppm)Chlorine (ppm)Comments DMH-1324 7/25/2023 DGM-8724 No Yes Colorless Fast 1.75 ft/sec or Greater 0.2 0.25 2 DMH-1324 7/25/2023 DGM-4687 Yes No N/A N/A ------DMH-1316 7/24/2023 DGM-4685 No No N/A N/A ------Outfall was inaccessible. DMH-1316 7/24/2023 DGM-4734 No No N/A N/A ------CB-5051 7/24/2023 DGM-4465 No Yes Colorless Fast 1.75 ft/sec or Greater 0.3 0.25 1.5 CB-5051 7/24/2023 DGM-4461 No No N/A N/A ------CB-5756 7/24/2023 DGM-5285 No Yes Colorless Medium 0.5-1.75 ft/sec <0.05 <0.125 0.04 CB-5756 7/24/2023 DGM-5313 No No N/A N/A ------DMH-1323 7/24/2023 DGM-7499 No No N/A N/A ------ DMH-1323 7/24/2023 DGM-6915 No No N/A N/A ------DMH-1315 7/24/2023 DGM-4670 No No N/A N/A ------ DMH-1315 7/24/2023 DGM-4672 No No N/A N/A ------OF-0188 7/25/2023 DGM-0188 No Yes Colorless Medium 0.5-1.75 ft/sec 0.1 0.25 0.26 DMH-1323 7/24/2023 DGM-8518 No No N/A N/A ------ DMH-0627 10/3/2023 DGM-2076 No No N/A N/A ------DMH-0627 10/3/2023 DGM-2041 No No N/A N/A ------ DMH-0629 10/3/2023 DGM-2078 No No N/A N/A ------OF-0287 8/21/2023 DGM-2079 Unknown Unknown N/A N/A ------Outfall was inaccessible. OF-0327 8/1/2023 DGM-2727 No Yes Colorless Unknown <0.05 <0.125 <0.02 CB-5674 7/18/2023 DGM-5193 No No N/A N/A ------ OF-0362 7/18/2023 DGM-5195 Yes No N/A N/A ------DMH-1452 7/18/2023 DGM-5192 Yes No N/A N/A ------ DMH-1452 7/18/2023 DGM-5194 Yes No N/A N/A ------ CB-5672 7/24/2023 DGM-5189 No Yes Colorless Slow 0-0.5 ft/sec 0.1 <0.125 <0.02CB-5673 7/18/2023 DGM-5190 No Yes Colorless Slow 0-0.5 ft/sec 0.1 0.25 <0.02 OF-0363 7/18/2023 DGM-5191 Yes No N/A N/A ------ OF-0382 10/3/2023 DGM-6453 No No N/A N/A ------DMH-0639 9/5/2023 DGM-2051 No No N/A N/A ------ DMH-1749 9/5/2023 DGM-6461 No No N/A N/A ------ OF-0394 8/21/2023 DGM-6460 Yes No N/A N/A ------ OF-0399 8/1/2023 DGM-6484 No No N/A N/A ------ DMH-1760 7/31/2023 DGM-6515 No Yes Colorless Slow 0-0.5 ft/sec <0.05 <0.125 <0.02DMH-1760 7/31/2023 DGM-6513 No Yes Colorless Medium 0.5-1.75 ft/sec <0.05 0.5 <0.02 OF-0400 7/31/2023 DGM-6514 No Yes Colorless Medium 0.5-1.75 ft/sec <0.05 0.5 0.04 DMH-1764 7/31/2023 DGM-6501 No No N/A N/A ------ DMH-1763 7/31/2023 DGM-6504 Yes No N/A N/A ------ DMH-1763 7/31/2023 DGM-6506 No No N/A N/A ------ OF-0401 7/31/2023 DGM-6507 Unknown Unknown N/A N/A ------Could not locate. OF-0363 OF-0394 OF-0382 OF-0399 OF-0400 OF-0188 OF-0287 OF-0327 OF-0362 OF-0401 Lexington, MA (0227871.17) Attach B - CI Results Page 3 of 4 Woodard Curran, Inc. June 2024 Attachment B: Catchment Investigation Screening Results MS4 General Permit Illicit Discharge Detection and Elimination Program Permit Years 6 Catchment Investigation Summaries Lexington, MA Infrastructure ID Inspection Date Pipe ID Standing Water Flow Flow Color Velocity Ammonia (ppm)Surfactants (ppm)Chlorine (ppm)Comments DMH-1769 8/1/2023 DGM-6490 No No N/A N/A ------ DMH-1769 8/1/2023 DGM-6492 No No N/A N/A ------OF-0402 7/31/2023 DGM-6491 Unknown Unknown N/A N/A ------Could not locate. DMH-1773 7/31/2023 DGM-8200 No No N/A N/A ------ DMH-1773 7/31/2023 DGM-6522 No No N/A N/A ------OF-0403 7/31/2023 DGM-6525 Yes No N/A N/A ------ OF-0435 7/24/2023 DGM-8710 No No N/A N/A ------ OF-0437 7/24/2023 DGM-5246 No Yes Yellow Medium 0.5-1.75 ft/sec 0.1 <0.125 <0.02 DMH-1456 7/24/2023 DGM-5231 No Yes Colorless Slow 0-0.5 ft/sec 0.2 <0.125 0.11DMH-1456 7/24/2023 DGM-5229 No Yes Colorless Medium 0.5-1.75 ft/sec <0.05 <0.125 0.86 DMH-1456 7/24/2023 DGM-5228 No Yes Yellow Medium 0.5-1.75 ft/sec <0.05 <0.125 1.97DMH-1461 7/24/2023 DGM-5240 No No N/A N/A ------ DMH-1461 7/24/2023 DGM-5233 No Yes Yellow Medium 0.5-1.75 ft/sec 0.2 <0.125 0.14Notes: 1. Bolded concentrations are above MS4 General Permit individual threshold criteria for potential illicit discharges. 2. Shaded cells indicate locations where all MS4 General Permit threshold criteria for potential illicit discharges were exceeded or where visual evidence of an illicit discharge was observed. 3. ND = Not Detected. 4. -- = Not Tested. OF-0403 OF-0437 OF-0402 OF-0435 Lexington, MA (0227871.17) Attach B - CI Results Page 4 of 4 Woodard Curran, Inc. June 2024 Lexington, MA (0227871.17) Woodard & Curran, Inc. Lexington, MA MS4 PY6 Catchment Investigation Memo July 2024 ATTACHMENT C: SURFICIAL DRAINAGE INFRASTRUCTURE CONDITIONS Attachment C: Surficial Drainage Infrastructure Conditions MS4 General Permit Illicit Discharge Detection and Elimination Program Permit Years 6 Catchment Investigation Summaries Lexington, MA Infrastructure ID Location Inspection Date Infrastructure Grade Pavement Condition Cover Condition Frame Condition Corbel Condition Floor Condition Corbel Construction Material Walls Construction Material Comments DMH-0128 DMH-0018 Waltham St 10/3/2023 At Grade Does Not Exist Good Good Good Not Visible Precast Concrete Concrete Block --DMH-1045 CB-4049 Fletcher Ave 10/3/2023 At Grade Good Good Good Good Not Visible Concrete Block Concrete Block --OF-0032 OF-0032 Byron Ave 8/1/2023 N/A N/A N/A N/A N/A N/A N/A N/A Standing water/submerged. DMH-0515 Byron Ave 9/5/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block Bricks and sediment in pipes/channel.OF-0034 OF-0034 Marrett Rd 9/5/2023 N/A N/A N/A N/A N/A N/A N/A N/A Unable to access outfall, heavily vegetated. CB-1667 Marrett Rd 8/21/2023 At Grade Good Good Good Good Not Visible Concrete Block Concrete Block --OF-0036 OF-0036 Churchill Ln 8/1/2023 N/A N/A N/A N/A N/A N/A N/A N/A Erosion present from rain. OF-0046CB-1967 Carville Ave 9/5/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block -- CB-1975 Ames Ave 9/5/2023 At Grade Good Good Good Good Good Concrete Block Brick -- CB-1973 Ames Ave 8/1/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block Unmapped SW inlet, SDE mapped inlet in the field. OF-0046 Carville Ave 8/21/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- CB-1969 Carville Ave 8/21/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block Unmapped SE inlet, SDE mapped inlet in the field. OF-0054 CB-8074 Circle Rd 7/18/2023 At Grade Good Good Good Good Not Visible Precast Concrete Precast Concrete -- OF-0056OF-0056 Ablemarle Ave 7/25/2023 N/A N/A N/A N/A N/A N/A N/A N/A Fishy odor. OF-0057 CB-2157 Lowell St 8/21/2023 At Grade Good Good Good Good Good Concrete Block Concrete Block Mapped as a catch basin but is actually a manhole.CB-2151 Lowell St 7/31/2023 At Grade Good Good Good Good Good Brick Concrete Block -- OF-0057 Lowell St 10/3/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- CB-2154 Summer St 7/31/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block --OF-0059 CB-2162 Bartlett Ave 7/31/2023 At Grade Good Good Good Good Not Visible Precast Concrete Precast Concrete --OF-0059 Bartlett Ave 8/21/2023 N/A N/A N/A N/A N/A N/A N/A N/A Standing water/ submerged. CB-2167 Bartlett Ave 7/24/2023 At Grade Good Good Good Good Not Visible Precast Concrete Precast Concrete -- OF-0078DMH-2066 Lowell St 10/3/2023 At Grade Good Good Good Good Good Precast Concrete Precast Concrete -- DMH-0843 Lowell St 10/3/2023 At Grade Does Not Exist Good Good Good Not Visible Brick Brick -- CB-3162 Fairlawn Ln 10/3/2023 At Grade Good Good Good Good Not Visible Concrete Block Concrete Block --CB-3160 Fairlawn Ln 10/3/2023 At Grade Good Good Good Good Not Visible Concrete Block Concrete Block -- DMH-0781 Whipple Rd 10/3/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block -- CB-3171 Fiske Rd 9/5/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block --DMH-0871 Fiske Rd 9/5/2023 At Grade Good Good Good Good Not Visible Concrete Block Brick Unmapped NW inlet. SDE mapped inlet in the field. Inlet sandbagged. DMH-0784 Locke Ln 9/5/2023 At Grade Good Good Good Good N/A Brick Concrete Block Mapped as a manhole but is actually a catch basin. CB-3187 Wheeler Rd 8/29/2023 At Grade Good Good Good Good N/A Brick Concrete Block --DMH-0787 Whipple Rd 8/29/2023 At Grade Good Good Good Good Good Concrete Block Concrete Block -- CB-3138 Wheeler Rd 8/29/2023 At Grade Good Good Good Not Visible Good Unknown Concrete Block Unable to see floor material due to sediment build up.DMH-0842 Bartlett Ave 8/29/2023 N/A N/A N/A N/A N/A N/A N/A N/A Could not locate. CB-3144 Locke Ln 8/29/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block Need to return to bag NE inlet and dry inlet. CB-3149 Fiske Rd 8/29/2023 At Grade Good Good Good Good Good Concrete Block Concrete Block Need to return to sandbag NW inlet.DMH-2013 Fairlawn Ln 8/29/2023 N/A N/A N/A N/A N/A N/A N/A N/A Could not locate. OF-0078 Bartlett Ave 9/5/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- DMH-0865 Lowell St 8/29/2023 N/A N/A N/A N/A N/A N/A N/A N/A Could not locate.OF-0080 OF-0080 Emerson Gardens Rd 9/5/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- OF-0114CB-3715 Fulton Ave 8/1/2023 At Grade Good Good Good Good Good Brick Concrete Block -- CB-3729 Fulton Ave 8/1/2023 At Grade Good Good Good Good Not Visible Concrete Block Concrete Block -- OF-0114 Lowell St 8/1/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- DMH-0992 Laconia St 8/1/2023 At Grade Good Good Good Good Good Brick Concrete Block -- CB-3712 Lowell St 8/1/2023 At Grade Good Good Good Good Good Concrete Block Concrete Block Mapped as catch basins but is actually a manhole. Inlet from CB-3710 does not appear to connect to CB-3712. OF-0188CB-5223 Freemont St 7/25/2023 At Grade Good Good Good Good Not Visible Concrete Block Concrete Block Significant infiltration. Suspect infiltration is coming from a water main SW of catch basin. DMH-1324 Freemont St 7/25/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block Unmapped NW inlet. SDE mapped inlet in the field. DMH-1315 Asbury St 7/24/2023 At Grade Good Good Good Good Good Brick Concrete Block --DMH-1316 Freemont St 7/24/2023 At Grade Good Good Good Good Good Brick Concrete Block -- CB-5051 Constitution Rd 7/24/2023 At Grade Good Fair Good Good Good Brick Brick -- CB-5756 Oxbow St 7/24/2023 At Grade Good Good Good Good Good Brick Concrete Block --OF-0188 Constitution Rd 7/25/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- DMH-1323 Bellflower St 7/24/2023 At Grade Good Good Good Good Good Brick Concrete Block Unmapped SE Inlet. SDE mapped inlet in the field. Sandbagged on 7/24. OF-0287DMH-0629 Fottler Ave 10/3/2023 At Grade Good Good Good Good Good Brick Concrete Block -- DMH-0627 Fottler Ave 10/3/2023 At Grade Good Good Good Good Good Brick Concrete Block -- OF-0287 Fottler Ave 8/21/2023 N/A N/A N/A N/A N/A N/A N/A N/A Outfall is inaccessible. Outfall discharges into culvert.OF-0327 OF-0327 Barrett Rd 8/1/2023 N/A N/A N/A N/A N/A N/A N/A N/A --OF-0362 CB-5675 Woodpark Cir 7/18/2023 At Grade Good Good Good Good Good Brick Brick Standing water. DMH-1452 Woodpark Cir 7/18/2023 At Grade Does Not Exist Good Good Good Good Brick Concrete Block Appears to be a culvert. Flow at beginning of culvert, standing water at outfall. Lexington, MA (0227871.17) Attach C - Structures Page 1 of 2 Woodard Curran, Inc. June 2024 Attachment C: Surficial Drainage Infrastructure Conditions MS4 General Permit Illicit Discharge Detection and Elimination Program Permit Years 6 Catchment Investigation Summaries Lexington, MA Infrastructure ID Location Inspection Date Infrastructure Grade Pavement Condition Cover Condition Frame Condition Corbel Condition Floor Condition Corbel Construction Material Walls Construction Material Comments CB-7186 Woodpark Cir 7/18/2023 At Grade N/A N/A N/A N/A Good Unknown Precast Concrete This structure is an inlet from a stream. Sample results: pH: 6.75 temp: 25.7 conductivity: 209 salinity: 0.1 A: 0.3 C:0 S:0.OF-0362 Woodpark Cir 7/18/2023 N/A N/A N/A N/A N/A N/A N/A N/A Standing Water/Submerged. CB-5674 Woodpark Cir 7/18/2023 At Grade Good Good Not Visible Not Visible N/A N/A N/A Standing Water/Submerged.OF-0363 CB-5672 Woodpark Cir 7/24/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block -- OF-0363 Woodpark Circ 7/18/2023 N/A N/A N/A N/A N/A N/A N/A N/A Standing Water/Submerged.CB-5673 Woodpark Cir 7/18/2023 At Grade Good Good Good Good Not Visible Brick Concrete Block -- OF-0382DMH-0639 Drew Ave 8/21/2023 At Grade Good Good Good Good Good Brick Concrete Block -- OF-0382 Bow St 8/21/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- OF-0394DMH-1749 S Rindge Ave 8/21/2023 At Grade Good Good Good Good Good Precast Concrete Precast Concrete -- OF-0394 S Rindge Ave 8/21/2023 N/A N/A N/A N/A N/A N/A N/A N/A Standing Water/Submerged. OF-0399OF-0399 Bartlett Ave 7/31/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- OF-0400 DMH-1760 Butterfield Rd 7/31/2023 At Grade Good Good Good Good Not Visible Precast Concrete Precast Concrete --OF-0400 Butterfield Rd 7/31/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- OF-0401 DMH-1764 Solomon Pierce Rd 7/31/2023 At Grade Good Good Good Good Not Visible Precast Concrete Precast Concrete --OF-0401 Solomon Pierce Rd 7/31/2023 N/A N/A N/A N/A N/A N/A N/A N/A Could not locate. DMH-1763 Solomon Pierce Rd 7/31/2023 At Grade Good Good Good Good Not Visible Precast Concrete Precast ConcreteOF-0402 DMH-1769 Solomon Pierce Rd 7/31/2023 At Grade Good Good Good Good Not Visible Precast Concrete Precast Concrete -- OF-0402 Solomon Pierce Rd 7/31/2023 N/A N/A N/A N/A N/A N/A N/A N/A Could not locate.OF-0403 DMH-1773 Joseph Comee Rd 7/31/2023 At Grade Good Good Good Good Not Visible Precast Concrete Precast Concrete OF-0403 Joseph Comee Rd 7/31/2023 N/A N/A N/A N/A N/A N/A N/A N/A Standing Water/Submerged. OF-0435 OF-0435 Wood St 7/24/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- OF-0437DMH-1461 Woodpark Cir 7/24/2023 At Grade Good Good Good Good Good Concrete Block Precast Concrete -- DMH-1456 Woodpark Cir 7/24/2023 At Grade Good Good Good Good Good Brick Precast Concrete --OF-0437 Woodpark Cir 7/24/2023 N/A N/A N/A N/A N/A N/A N/A N/A -- Lexington, MA (0227871.17) Attach C - Structures Page 2 of 2 Woodard Curran, Inc. June 2024