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HomeMy Public PortalAboutSemi Annual Report, July 1 to December 31, 20234 stormw'itpr February 13, 2024 Chief, Water Enforcement and Compliance Assurance Branch Water and Wetlands Protection Division U.S. ENVIRONMENTAL PROTECTION AGENCY, REGION 7 11201 Renner Blvd. Lenexa, KS 66219 RE: Metropolitan St. Louis Sewer District Consent Decree Semi-Annual Report - Reporting Period: July 1, 2023 to December 31, 2023 Greetings: Tire Metropolitan St. Louis Sewer District (MSD) is submitting this Semi-Annual Report pursuant to Consent Decree No. 4:07-CV-1120 (CEJ) entered April 27, 2012. Pursuant to the Consent Decree, this report provides data for Constructed SSO Activations, Building Backups, and Sanitary Sewer Overflows. Please find attached the following submissions: Semi-Annual Report - February 15, 2024 Appendix A - Constructed SSO Activations (07/01/2023-12/31/2023) Table A-l: Constracted SSO Activation Data Table A-2: Constructed SSO Activation Data - Excluded Events Appendix B - Building Backups (07/01/2023-12/31/2023) Table B-l: Building Backups Appendix C - Sanitary Sewer Overflows (07/01/2023-12/31/2023) Table C-l: Sanitary Sewer Overflows If you have questions related to this report which are not subject to paragraph 129 of the Consent Decree, please send them to me or by electronic mail at: CDQuestions@stlmsd.com Sincerely, Susan M. Myers General Counsel Metropolitan St. Louis Sewer District Enclosures: Certification Report Distribution Electronic Documentation on Enclosed Disk METROPOLITAN ST. LOUIS SEWER DISTRICT | 2350 MARKET STREET | ST. LOUIS, MO 63103-2555 (314)768-6260 | WWW.MSDPROJECTCLEAR.ORG Metropolitan St. Louis Sewer District Semi-Annual Report CERTIFICATION I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. The infonnation submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. BRIAN HOELSCHER, P.E. Executive Director Metropolitan St. Louis Sewer District DATE: Metropolitan St. Louis Sewer District Semi-Annual Report REPORT DISTRIBUTION United States: Chief, Environmental Enforcement Section Environment and Natural Resources Division U.S. Department of Justice Box 7611 Ben Franklin Station Washington, D.C. 20044-7611 Re: DOJ No. 90-5-1-1-08111 ERA: Chief, Water Enforcement and Compliance Assurance Branch Water and Wetlands Protection Division U.S. Environmental Protection Agency, Region 7 11201 Renner Blvd. Lenexa, KS 66219 David Cozad Regional Counsel Office of Regional Counsel U.S. Environmental Protection Agency, Region 7 11201 Renner Blvd. Lenexa, KS 66219 State of Missouri: Chief Counsel Agriculture and Environment Division State of Missouri Office of Attorney General 207 W. High Street Jefferson City, MO 65102 Chief, Water Pollution Compliance and Enforcement Section Missouri Department of Natural Resources P.O. Box 176 1101 Riverside Dr. Jefferson City, MO 65101 Director, St. Louis Regional Office Missouri Department of Natural Resources 7545 South Lindbergh Blvd., Suite 210 St. Louis, MO 63125 Coalition: Jared Opsal Executive Director Missouri Coalition for the Environment 725 Kingsland Ave, Suite 100 St. Louis, MO 63130 Maxine I. Lipeles Elizabeth J. Hubertz Interdisciplinary Environmental Clinic Washington University School of Law One Brookings Drive Campus Box 1120 St. Louis, MO 63130 MSD: Executive Director Metropolitan St. Louis Sewer District 2350 Market Street St. Louis, MO 63103-2555 General Counsel Metropolitan St. Louis Sewer District 2350 Market Street St. Louis, MO 63103-2555 Director of Engineering Metropolitan St. Louis Sewer District 2350 Market Street St. Louis, MO 63103-2555 Metropolitan St. Louis Sewer District Semi-Annual Report ELECTRONIC DOCUMENTATION ON ENCLOSED DISK REPORT PDF 2023_12 Semi.pdf APPENDIX A FOLDER 2023 12 Semi A1-2 sso activation.xls APPENDIX B FOLDER 2023_12 Semi Bl backup.xls APPENDIX C FOLDER 2023 12 Semi Cl known sso.xls Reporting Period – July 1, 2023 to December 31, 2023 Consent Decree Due Date – February 15, 2024 Metropolitan St. Louis Sewer District SEMI-ANNUAL REPORT Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 TABLE OF CONTENTS 1.0 INTRODUCTION ......................................................................................... 1 2.0 CONSTRUCTED SSO ACTIVATION DATA .............................................. 2 3.0 BUILDING BACKUP DATA ....................................................................... 7 4.0 SANITARY SEWER OVERFLOW DATA ................................................... 9 5.0 CONCLUSION .......................................................................................... 12 LIST OF APPENDICES APPENDIX A: CONSTRUCTED SSO ACTIVATIONS Table A-1 – Constructed SSO Activation Data Table A-2 – Constructed SSO Activation Data – Excluded Events APPENDIX B: BUILDING BACKUPS Table B-1 – Building Backups APPENDIX C: SANITARY SEWER OVERFLOWS Table C-1 – Sanitary Sewer Overflows Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 1 1.0 INTRODUCTION A Consent Decree, with an Effective Date of April 27, 2012, was entered into between the United States of America, the Missouri Coalition for the Environment Foundation, and the Metropolitan St. Louis Sewer District (“MSD”) in the matter of The United States, et al. v. The Metropolitan St. Louis Sewer District, Case No. 4:07-CV-1120-CEJ (E.D. Mo.). MSD prepared this Semi-Annual Report in compliance with paragraph VIII.72 of the Consent Decree. The submission date of this Semi-Annual Report is August 15, 2023 and provides reporting data for the six-month period of July 1, 2023 to December 31, 2023. This Semi-Annual Report includes the following: • Constructed SSO Activation Data (satisfies Consent Decree requirement VIII.72.a) • Building Backup Data (satisfies Consent Decree requirement VIII.72.b) • Sanitary Sewer Overflow Data (satisfies Consent Decree requirement VIII.72.c) Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 2 2.0 CONSTRUCTED SSO ACTIVATION DATA Pursuant to the requirements set forth in paragraph VIII.72.a of the Consent Decree, the Constructed SSO discharge activations that occurred during the six-month reporting period covered in this Semi-Annual Report are listed in Appendix A. The Constructed SSO discharge activation data for MSD’s service area is recorded in a Telog software system. The Telog software has embedded alert formulas that are used to validate field equipment alarms. Site inspection following field equipment alarms is part of MSD’s validation process. Constructed SSO discharge activations determined to be valid are identified in Table A-1. Constructed SSO discharge activations determined to be excluded from the valid data are identified in Table A-2. Activations were excluded from the valid data because: (1) the activations did not meet the pre-set overflow level and voltage requirements for the Telog formula; or (2) a site inspection determined that the activation was not valid based on certain conditions at the outfall (e.g. low battery, bad sensor, debris stuck in the valve, etc.). For the this reporting period of July 1, 2023 – December 31, 2023, there are no discharge activations to report in Table A-2 that were found to be excluded from the valid data. The Constructed SSO activation data included in this report detail activations of the field equipment alarms. Please note, however, that there will be instances where there may be more than one field equipment alarm for a single Constructed Sanitary Sewer Overflow or discharge. This situation occurs from time to time due to intermittent or variable flow conditions within the Sewer System. More particularly, the rubber duck bill valves open and close depending on the amount of pressure provided by the flows within the Sewer System. For the Constructed SSO discharge activation data provided, MSD has included: (i) the Constructed SSO Outfall number; (ii) address; (iii) the start date of the event; (iv) the event duration; and (v) the estimated volume, if known. The column headings of Table A-1 and Table A-2 in Appendix A represent the following information: Bypass Number The bypass number provided is designated by MSD’s Constructed SSO Outfall Inventory. Address, Zip Code The address and zip code of the site provided is designated by MSD’s Constructed SSO Outfall Inventory. Event Start Date, Event End Date These are the date/timestamps representing the start and stop time recorded for this event by the Telog software. Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 3 Event Duration (day hh:mm:ss) This is the information recorded by the Telog software and represents the duration time of the event. The Telog software measures this time in two and one half minute increments. Estimated Volume (gallons) The estimated volume is reported as “unknown” for the majority of valid activations that occurred during this reporting period. Most of the existing monitoring equipment only measures water level, not velocity, which makes any flow volume calculation inaccurate and highly unreliable. All new and replacement flow monitors installed after April 27, 2012 include the capability to measure level and velocity so that a flow rate and subsequent volume may be calculated. MSD provides estimated discharge volume when both level and velocity outputs indicate predictable flow duration curve response during a valid event. Although estimated discharge volumes can be calculated, the quality of the data is questionable due to the less than ideal pipe characteristics for placing the flow meter. More particularly and according to the manufacturer’s recommendations for installation, the flow meter provides the best results in flow streams with uniform flow (not intermittent or variable flow conditions). The manufacturer of the flow meter advises that poor channel conditions may cause incorrect or erratic readings. Areas to avoid pursuant to the manufacturer are: • Outfalls or channel intersections • Flow streams at very low levels with high flow rates • Turbulence • Channel sections that are apt to collect debris or silt • Depths that consistently run below 1 inch All of the flow meter installations are in areas exhibiting most, if not all, of these poor channel conditions. As a result, the reported estimated volumes are likely inaccurate. As of December 31, 2023, MSD has installed ten (10) flow monitors with the capability to measure level and velocity. In some instances, the flow data was found to be completely unacceptable and therefore, was not used for estimating discharge volume. An example of this would be when the meter records negative or zero-value velocities due to backflow or turbulent conditions. Another example would be when the meter records erratic level values due to a faulty sensor. MSD, however, makes good faith and reasonable efforts to obtain accurate volume data whenever possible. Pursuant to subparagraph V.C.15.e of the Consent Decree and in the event MSD cannot obtain accurate velocity data within six months of installation, the equipment can revert to the level-only monitoring setup. Although MSD identified flow meter installations Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 4 meeting this condition more than a year ago (i.e., MSD was unable to obtain accurate velocity data), MSD elected to leave all flow monitors installed to date in service. MSD has historically gone above and beyond Consent Decree obligations regarding the maintenance of the flow meters at these Constructed SSO locations. Due to the concern over flow meter data quality, MSD has maintained two separate systems at the Constructed SSO locations (flow meters and level-only sensors with rubber duck bill valve sensors). However, as the number of area velocity meter locations increase and the amount of accurate velocity data decreases, MSD believes that it is prudent to reduce the time and effort spent on maintaining two separate systems. Moving forward, MSD will invoke subparagraph V.C.15.e of the Consent Decree by actively removing the flow meters in locations that do not provide accurate velocity data within six months of installation. Based on our most recent evaluation, MSD has identified a number of flow meter installations that cannot obtain accurate velocity data and will be removed pursuant to the Consent Decree. MSD did not remove any flow meters during this reporting period, July 1, 2023 through December 31, 2023 as a result of inaccurate velocity data. MSD previously removed flow meters from these locations: • BP-001 at 4705 Upshaw – The flow monitor capable of measuring level and velocity was installed on February 5, 2013 and removed on April 14, 2017. • BP-004 at 1 Cedar Crest – The flow monitor capable of measuring level and velocity was installed on September 16, 2015 and removed on April 14, 2017. • BP-013 at 842 Louwen Drive – The flow monitor capable of measuring level and velocity was installed on April 3, 2015 and removed on December 7, 2016. • BP-014 at 100 McKnight Rd – The flow monitor capable of measuring level and velocity was installed on June 1, 2015 and removed on April 19, 2017. • BP-017 at 126 Pointer Ln – The flow monitor capable of measuring level and velocity was installed on October 22, 2015 and removed on August 2, 2017. • BP-024 at 2338 Goodale – The flow monitor capable of measuring level and velocity was installed on June 12, 2015 and removed on August 19, 2016. • BP-036 at 1593 Narrows – The flow monitor capable of measuring level and velocity was installed on September 20, 2014 and removed on April 12, 2017. • BP-069 at 1217 Crested View Drive – The flow monitor capable of measuring level and velocity was installed on May 23, 2018 and removed on July 1, 2019. Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 5 • BP-087 at 11749 Westport Crossing Dr – The flow monitor capable of measuring level and velocity was installed on January 27, 2016 and removed on July 12, 2019. • BP-110 at 610 St. Marie – The flow monitor capable of measuring level and velocity was installed on April 18, 2018 and removed on May 29, 2020. • BP-141 at 245 Palm Dr – The flow monitor capable of measuring level and velocity was installed on December 14, 2012 and removed on August 3, 2017. • BP-145 at 2529 Sims Ave – The flow monitor capable of measuring level and velocity was installed on January 7, 2016 and removed on August 2, 2017. • BP-155 at 23 Warson Terrace – The flow monitor capable of measuring level and velocity was installed on April 8, 2019 and removed on May 4, 2020. • BP-170 at 10042 Conway Rd – The flow monitor capable of measuring level and velocity was installed on December 11, 2012 and removed on April 13, 2017. • BP-198 at 1324 Rock Hill Road – The flow monitor capable of measuring level and velocity was installed on April 10, 2015 and removed on August 30, 2016. • BP-287 at 10063 Coburgh Lands – The flow monitor capable of measuring level and velocity was installed on January 30, 2016 and removed on April 14, 2017. • BP-305 at 701 Marvin – The flow monitor capable of measuring level and velocity was installed on December 14, 2012 and removed on April 14, 2017. • BP-348 at 24 Overbrook – The flow monitor capable of measuring level and velocity was installed on February 29, 2016 and removed on June 27, 2019. • BP-349 at 25 Overbrook Lane – The flow monitor capable of measuring level and velocity was installed on March 1, 2016 and removed on August 30, 2016. • BP-370 at 7501 Capilia Dr – The flow monitor capable of measuring level and velocity was installed on August 21, 2015 and removed on June 5, 2018. • BP-382 at 9415 Gates Manor – The flow monitor capable of measuring level and velocity was installed on July 16, 2015 and removed on April 12, 2017. • BP-421 at 8507 Crixdale – The flow monitor capable of measuring level and velocity was installed on March 11, 2013 and removed on April 19, 2017. Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 6 • BP-440 at 219 Old Orchard – The flow monitor capable of measuring level and velocity was installed on September 25, 2015 and removed on March 4, 2020. • BP-454 at 7711 St. Charles Rock Road – The flow monitor capable of measuring level and velocity was installed on May 11, 2018 and removed on July 11, 2019. • BP-457 at 7700 Underhill Drive – The flow monitor capable of measuring level and velocity was installed on July 2, 2014 and removed on July 12, 2019. • BP-515 at 9443 Kirchner – The flow monitor capable of measuring level and velocity was installed on June 22, 2015 and removed on March 10, 2020. • BP-516 at 2559 Rolens – The flow monitor capable of measuring level and velocity was installed on October 18, 2014 and removed on August 22, 2016. • BP-527 at 8240 Lindbergh Boulevard – The flow monitor capable of measuring level and velocity was installed on December 14, 2012 and removed on August 19, 2016. • BP-545 at 1100 Des Peres Drive – The flow monitor capable of measuring level and velocity was installed on June 10, 2013 and removed on September 15, 2016. • BP-591 at 10201 Lylewood Drive – The flow monitor capable of measuring level and velocity was installed on June 12, 2015 and removed on July 9, 2019 • BP-597 at 4429 Rolling Drive – The flow monitor capable of measuring level and velocity was installed on April 19, 2013 and removed on October 5, 2016. • BP-599 at 8711 Pardee Lane – The flow monitor capable of measuring level and velocity was installed on April 10, 2019 and removed on July 17, 2019. • BP-618 at 9058 Rosemary Avenue – The flow monitor capable of measuring level and velocity was installed on December 3, 2014 and removed on December 30, 2016. • BP-623 at 8024 Walinka – The flow monitor capable of measuring level and velocity was installed on July 21, 2016 and removed on April 13, 2017. • BP-624 at 8901 Broadway – The flow monitor capable of measuring level and velocity was installed on December 8, 2014 and removed on August 19, 2016. • BP-634 at 7575 Oxford – The flow monitor capable of measuring level and velocity was installed on July 3, 2013 and removed on August 19, 2016. Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 7 3.0 BUILDING BACKUP DATA Pursuant to Consent Decree requirement VIII.72.b, Building Backups that occurred during the six-month period covered in this Semi-Annual Report are listed in Appendix B. The Building Backup data included in Table B-1 was generated from MSD’s computerized maintenance management system. Due to certain limitations with MSD’s computerized maintenance management system, however, a Building Backup in a multi-unit building with different numerical street addresses for each unit within the same building (e.g., an apartment building) are reported as separate occurrences. MSD reports these Building Backups as separate occurrences even though the Building Backup occurred in a single building at the same time. During this reporting period, there were also Building Backups which resulted from water main breaks. Those Building Backups are not included in this report because an investigation by MSD led to the conclusion that these backups were the result of private property defects and did not result from blockages, flow conditions or malfunctions within the Sewer System. Additionally, this data includes occurrences that were the result of the failure of a sewer separation device within a private lateral. Although these backups are the result of a failed sewer separation device, they are reported as Building Backups when caused by blockages, flow conditions, or malfunctions within the Sewer System. Ongoing investigations may result in the cause or causes of certain Building Backups to be reclassified (i.e. blocked main, sewer separation failure, overcharged main, pump station failure, etc.). These changes will not be addressed in the narrative, however may be apparent in future reports should reoccurring Building Backups happen at a given address. When Building Backups occur in the last weeks of a reporting period, they are sometimes not resolved in sufficient time to be included in their respective Semi-Annual Report. Customers have 30 days to report a possible backup and MSD has 30 days to evaluate the backup claim. This total of 60 days exceeds the reporting deadline for Semi-Annual Reports that are due 45 days after the reporting period. MSD identified fifteen (15) Building Backups that occurred during the January 1, 2023 to June 30, 2023 reporting period that were not included in the August 15, 2023 Semi-Annual Report. These fifteen (15) Building Backups are included in Table B-1 of this report and are identified with an asterisk. For the Building Backup data provided, MSD has included: (i) street address at which the Building Backup occurred; (ii) identification of the Watershed/Treatment Plant Service Area in which the Building Backup occurred; (iii) cause or causes of the Building Backup, if known; (iv) call date(s) of any Building Backup(s) that have previously occurred at the same address since the Effective Date of April 27, 2012; and (v) an indication for those Building Backups that have resulted in a discharge to waters of the United States Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 8 (“WOTUS”). The column headings of Table B-1 in Appendix B represent the following information: Service Request Call Date This is the date that MSD received a call from a customer reporting a building backup as recorded in MSD’s computerized maintenance management system. Occurred During Current Reporting Period? This column identifies those building backups that occurred during the current reporting period in order to denote those that previously occurred at the same address since the Effective Date of April 27, 2012. Street Number, Street Name, Zip Code This is the location information that has been recorded in MSD’s computerized maintenance management system by MSD customer care staff. The service address information provided includes a street number, street name and zip code. Watershed/Treatment Plant Service Area The watershed indicated is a wastewater collection area upstream of one (1) of the seven (7) MSD wastewater treatment plants. Service Request Work Order Cause This is the cause or resolution information which has been recorded by MSD staff in MSD’s computerized maintenance management system. Discharge to Waters of the US? This column indicates whether a Building Backup event resulted in a discharge to the WOTUS. An example of how this could occur is if a homeowner has a sump pump in their basement for the purpose of removing groundwater and therefore the homeowner pumps the sewage to the WOTUS. Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 9 4.0 SANITARY SEWER OVERFLOW DATA Pursuant to Consent Decree requirement VIII.72.c, all known Sanitary Sewer Overflows that occurred during the six-month reporting period covered by this Semi-Annual Report are listed in Appendix C. The known Sanitary Sewer Overflow data (other than Constructed SSO activations and Building Backups) is included in Table C-1 and was generated from MSD’s computerized maintenance management system. Per the Consent Decree definition of Sanitary Sewer Overflow, the data only includes overflows, spills, diversions and releases of wastewater from or caused by MSD’s sanitary sewer system. The data does not include overflows for MSD’s combined sewer system. Copies of all unpermitted CSO discharge reports submitted to MDNR will be provided with the Consent Decree Annual Report. MSD, on occasion, receives initial notification of a Sanitary Sewer Overflow occurrence reported by an MSD customer or by a third party. MSD responds as expeditiously as possible, normally within four (4) hours. Instances with extended response times are typically due to the Sanitary Sewer Overflow being first identified as a different problem, such as an odor complaint from a customer. For the Sanitary Sewer Overflow data provided, MSD has included: (i) Watershed/Treatment Plant Service Area where the Sanitary Sewer Overflow occurred; (ii) location description; (iii) facility type; (iv) volume, if known; (v) reason such as blockage, broken pipe, weather conditions, power outage, vandalism, third-party cause, Mississippi River backflow; (vi) cause such as debris, grit, grease, high river flow; (vii) the amount of time to commence investigation of each SSO, as reported; and (viii) the amount of time to correct and/or cleanup each SSO, as necessary. The column headings of Table C-1 in Appendix C represent the following information: Work Order Start Date This is the date of the initial notification to MSD’s Division of Environmental Compliance (“DEC”) after an MSD Operations Crew has arrived onsite and determined that an SSO occurred. DEC records information related to the overflow using a work order in MSD’s computerized maintenance management system. Watershed/Treatment Plant Service Area The watershed indicated is a wastewater collection area upstream of one (1) of the seven (7) MSD wastewater treatment plants. Service Address This is the work order service address location information that has been recorded in MSD’s computerized maintenance management system. This information represents the best address that a MSD Staff member who responded on site determined relates to the overflow. The service address includes a street number, street name and zip code. Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 10 Location Description The location description listed is an MSD collection system structure such as a manhole, gravity main or pump station. These MSD collection system structures denote respective GIS coordinates, when available. Facility Type The facility type indicates the type of MSD collection system structure determined to be source of the Sanitary Sewer Overflow. Estimated Volume (gallons) The estimated volume of the Sanitary Sewer Overflow is indicated in gallons, if known. The estimated volume provided is determined to the best of MSD’s ability, which accounts for the period of time MSD knew about the overflow and the estimated dry weather flow for the sewer from which the Sanitary Sewer Overflow is released. Other factors are used to make this estimation when appropriate. Reason/Cause The reason and the cause for the Sanitary Sewer Overflow are indicated in this combined field under a single column heading. Time To Commence Investigation (day hh:mm) This is the duration of time starting at the initial notification of an SSO up until an MSD Operations Crew has arrived on site to investigate the problem. If the time to commence the investigation is zero that is due to the fact that the Sanitary Sewer Overflow was discovered by an MSD crew or staff member. Time To Correct and/or Cleanup (day hh:mm) This is duration of time starting from when the MSD Operations Crew arrives on site to correct the problem and/or cleanup (as necessary) until the time the Sanitary Sewer Overflow as defined by the Consent Decree has ceased and/or the cleanup effort is completed whichever is later. During this current reporting period there were five (5) sanitary sewer failure events that resulted in the release of wastewater at multiple locations. Although each event was attributable to a single sanitary sewer failure, MSD has separately listed each of the multiple locations having a wastewater release. During the period of July 1, 2023 to December 31, 2023, a total of sixty-five (65) events caused overflows at seventy (70) locations. The details of these events that overflowed at more than one location are described as follows: • On July 19, 2023, a gravity sewer main in the Grand Glaize Treatment Plant service area was blocked with debris. The blockage resulted in sewage being released from the service lateral cleanouts on two separate properties (1000 Weidman Rd and 1004 Weidman Rd) connected to the Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 11 same blocked main (GIS-2513744). Two (2) entries in Table C-1 are related to this one (1) event. • On September 7 and 9, 2023, a broken force main in the Lemay Treatment Plant service area required extensive excavation, establishing a temporary pump and haul, and taking a pump station offline to make repairs. Sewage was released from two (2) locations (E10645 and E11952). Two (2) entries in Table C-1 are related to this one (1) event. • On September 14 and 15, 2023, a gravity sewer main in the Fenton Treatment Plant service area was blocked with debris. The blockage resulted in sewage being released from the service lateral cleanouts on two separate properties (11048 Gravois Industrial Ct. and 11085 Gravois Industrial Ct.) connected to the same blocked main (GIS-2531993). Two (2) entries in Table C-1 are related to this one (1) event. • On November 11, 2023, a gravity sewer main in the Grand Glaize Treatment Plant service area was blocked with debris. Sewage was initially found to be released from one location (GIS-1565557). During cleanup the following day, November 12, 2023, a second discharge site was discovered (GIS-1565556). Two (2) entries in Table C-1 are related to this one (1) event. • On November 13, 2023, a gravity sewer main in the Grand Glaize Treatment Plant service area was blocked with debris. The blockage resulted in sewage being released from two (2) locations (GIS-2418226 and GIS-1552304). Two (2) entries in Table C-1 are related to this one (1) event. Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 12 5.0 CONCLUSION MSD has provided the information contained in this Semi-Annual Report to comply with paragraph VIII.72 of the Consent Decree Case No. 4:07-CV-1120-CEJ. Any questions regarding the content of this Semi-Annual Report can be directed to MSD’s Legal Department. If you have questions related to this report which are not subject to paragraph XVII.129 of the Consent Decree, please send them by letter or email to: Susan M. Myers General Counsel Metropolitan St. Louis Sewer District 2350 Market Street St. Louis, MO 63103 or Electronic mail at: CDQuestions@stlmsd.com Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 APPENDIX A: CONSTRUCTED SSO ACTIVATIONS CONSTRUCTED SSO ACTIVATIONS Attached and Spreadsheet File Provided on Enclosed Disk Metropolitan St. Louis Sewer District Semi-Annual Report Bypass Number Address Zip Code Event Start Date Event End Date Event Duration (day hh:mm:ss) Estimated Volume (gallons) BP-013 842 LOUWEN DRIVE 63124 7/1/2023 16:27 7/1/2023 17:02 0:35:00 N/A BP-013 842 LOUWEN DRIVE 63124 7/17/2023 2:50 7/17/2023 2:55 0:05:00 N/A BP-013 842 LOUWEN DRIVE 63124 8/5/2023 4:37 8/5/2023 5:20 0:42:30 N/A BP-158 1182 GLENWAY DRIVE 63122 7/14/2023 23:17 7/14/2023 23:52 0:35:00 1,724 BP-158 1182 GLENWAY DRIVE 63122 8/5/2023 4:35 8/5/2023 5:02 0:27:30 412 BP-454 7711 ST CHARLES ROCK RD 63114 8/5/2023 4:12 8/5/2023 4:30 0:17:30 N/A BP-501 907 WARSON WOODS DRIVE (B)63122 7/14/2023 23:27 7/14/2023 23:50 0:22:30 N/A BP-605 22 HILLVALE 63105 8/5/2023 4:30 8/5/2023 4:37 0:07:30 133 BP-623 8024 WALINCA 63105 7/1/2023 16:12 7/1/2023 16:15 0:02:30 N/A BP-634 7575 OXFORD 63105 7/1/2023 16:07 7/1/2023 16:27 0:20:00 N/A BP-634 7575 OXFORD 63105 7/17/2023 2:47 7/17/2023 2:57 0:10:00 N/A BP-634 7575 OXFORD 63105 8/5/2023 4:10 8/5/2023 4:17 0:07:30 N/A BP-634 7575 OXFORD 63105 8/5/2023 4:30 8/5/2023 4:45 0:15:00 N/A (07/01/2023 - 12/31/2023) Table A-1: Constructed SSO Activation Data 2023_12 Semi A1-2 SSO Activation Page 1 of 1 Metropolitan St. Louis Sewer District Semi-Annual Report Bypass Number Address Zip Code Event Start Date Event End Date Event Duration (day hh:mm:ss) Estimated Volume (gallons) Table A-2: Constructed SSO Activation Data - Excluded Events (07/01/2023 - 12/31/2023) 2023_12 Semi A1-2 SSO Activation Page 1 of 1 Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 APPENDIX B: BUILDING BACKUPS BUILDING BACKUPS Attached and Spreadsheet File Provided on Enclosed Disk Metropolitan St. Louis Sewer District Semi-Annual Report Service Request Call Date Occurred During Current Reporting Period Street Number Street Name Zip Code Watershed/Treatment Plant Service Area Service Request Work Order Cause Discharge to Water of the US? 1/25/2018 20 ALLEN 63119 LEMAY TREATMENT BLOCKED MAIN NO2/19/2020 20 ALLEN 63119 LEMAY TREATMENT BLOCKED MAIN NO1/27/2022 20 ALLEN 63119 LEMAY TREATMENT BLOCKED MAIN NO12/26/2023 X 20 ALLEN 63119 LEMAY TREATMENT BLOCKED MAIN NO9/14/2023 X 307 ALTUS 63122 GRAND GLAIZE TREATMENT BLOCKED MAIN NO9/25/2023 X 307 ALTUS 63122 GRAND GLAIZE TREATMENT BLOCKED MAIN NO12/27/2015 6682 AMORA 63134 COLDWATER TREATMENT OVERCHARGED MAIN NO5/18/2017 6682 AMORA 63134 COLDWATER TREATMENT OVERCHARGED MAIN NO3/29/2023 6682 AMORA 63134 COLDWATER TREATMENT OVERCHARGED MAIN NO9/25/2023 X 6682 AMORA 63134 COLDWATER TREATMENT OVERCHARGED MAIN NO6/4/2019 5658 ARENDES 63116 LEMAY TREATMENT OVERCHARGED MAIN NO5/19/2022 5658 ARENDES 63116 LEMAY TREATMENT OVERCHARGED MAIN NO6/23/2023 * 5658 ARENDES 63116 LEMAY TREATMENT SEWER SEPARATION FAILURE NO5/23/2019 5702 ARENDES 63116 LEMAY TREATMENT OVERCHARGED MAIN NO5/19/2022 5702 ARENDES 63116 LEMAY TREATMENT OVERCHARGED MAIN NO6/19/2023 * 5702 ARENDES 63116 LEMAY TREATMENT SEWER SEPARATION FAILURE NO4/20/2017 1806 ATMORE 63136 BISSELL TREATMENT BLOCKED MAIN NO6/7/2019 1806 ATMORE 63136 BISSELL TREATMENT BLOCKED MAIN NO9/24/2021 1806 ATMORE 63136 BISSELL TREATMENT BLOCKED MAIN NO9/12/2023 X 1806 ATMORE 63136 BISSELL TREATMENT BLOCKED MAIN NO2/10/2021 14435 AVOCADO 63034 COLDWATER TREATMENT BLOCKED MAIN NO7/27/2022 14435 AVOCADO 63034 COLDWATER TREATMENT OVERCHARGED MAIN NO12/23/2023 X 14435 AVOCADO 63034 COLDWATER TREATMENT BLOCKED MAIN NO10/4/2023 X 135 BEAUJOLAIS 63031 MISSOURI RIVER TREATMENT BLOCKED MAIN NO5/17/2023 * 2621 BIG BEND 63143 LEMAY TREATMENT OVERCHARGED MAIN NO5/17/2023 * 2621 BIG BEND 63143 LEMAY TREATMENT OVERCHARGED MAIN NO5/17/2023 * 2621 BIG BEND 63143 LEMAY TREATMENT OVERCHARGED MAIN NO5/17/2023 * 2625 BIG BEND 63143 LEMAY TREATMENT OVERCHARGED MAIN NO5/17/2023 * 2625 BIG BEND 63143 LEMAY TREATMENT OVERCHARGED MAIN NO5/17/2023 * 2625 BIG BEND 63143 LEMAY TREATMENT OVERCHARGED MAIN NO10/18/2023 X 12 BON PRICE TERRACE 63132 LEMAY TREATMENT BLOCKED MAIN NO12/18/2023 X 13201 BONROYAL 63131 GRAND GLAIZE TREATMENT BLOCKED MAIN NO8/18/2023 X 147 BROOKTRAIL 63141 LEMAY TREATMENT BLOCKED MAIN NO8/14/2023 X 215 BUDDIE 63135 COLDWATER TREATMENT BLOCKED MAIN NO12/18/2023 X 2100 CEDAROYAL 63131 GRAND GLAIZE TREATMENT BLOCKED MAIN NO9/25/2023 X 17151 CHESTERFIELD AIRPORT 63005 MISSOURI RIVER TREATMENT BLOCKED MAIN NO4/29/2020 738 CLAY 63122 LEMAY TREATMENT BLOCKED MAIN NO7/23/2023 X 738 CLAY 63122 LEMAY TREATMENT BLOCKED MAIN NO12/27/2023 X 738 CLAY 63122 LEMAY TREATMENT BLOCKED MAIN NO6/9/2018 2621 CLIFFWOOD 63129 MERAMEC TREATMENT OVERCHARGED MAIN NO9/7/2023 X 2621 CLIFFWOOD 63129 MERAMEC TREATMENT BLOCKED MAIN NO (07/01/2023 - 12/31/2023, Effective Date 04/27/2012) Table B-1: Building Backup 2023_12 Semi B1 backup Page 1 of 5 Metropolitan St. Louis Sewer District Semi-Annual Report Service Request Call Date Occurred During Current Reporting Period Street Number Street Name Zip Code Watershed/Treatment Plant Service Area Service Request Work Order Cause Discharge to Water of the US? (07/01/2023 - 12/31/2023, Effective Date 04/27/2012) Table B-1: Building Backup 6/9/2018 2627 CLIFFWOOD 63129 MERAMEC TREATMENT OVERCHARGED MAIN NO9/7/2023 X 2627 CLIFFWOOD 63129 MERAMEC TREATMENT BLOCKED MAIN NO8/2/2023 X 963 COAL BANK 63138 BISSELL TREATMENT BLOCKED MAIN NO5/15/2023 * 1 DANIEL 63124 LEMAY TREATMENT SEWER SEPARATION FAILURE NO9/12/2023 X 8905 DARNELL 63136 BISSELL TREATMENT BLOCKED MAIN NO9/12/2023 X 8905 DARNELL 63136 BISSELL TREATMENT BLOCKED MAIN NO3/26/2013 2223 DORAN 63125 LEMAY TREATMENT BLOCKED MAIN NO12/1/2023 X 2223 DORAN 63125 LEMAY TREATMENT BLOCKED MAIN NO10/19/2023 X 1278 ENDERBURY 63125 LEMAY TREATMENT BLOCKED MAIN NO10/19/2023 X 1290 ENDERBURY 63125 LEMAY TREATMENT BLOCKED MAIN NO5/23/2019 3818 FEDERER 63116 LEMAY TREATMENT OVERCHARGED MAIN NO6/1/2022 3818 FEDERER 63116 LEMAY TREATMENT OVERCHARGED MAIN NO6/19/2023 * 3818 FEDERER 63116 LEMAY TREATMENT SEWER SEPARATION FAILURE NO7/31/2023 X 1041 FERNBROOK 63031 COLDWATER TREATMENT BLOCKED MAIN NO5/13/2015 8250 FROST 63134 COLDWATER TREATMENT BLOCKED MAIN NO6/26/2015 8250 FROST 63134 COLDWATER TREATMENT OVERCHARGED MAIN NO10/7/2023 X 8250 FROST 63134 COLDWATER TREATMENT BLOCKED MAIN NO9/14/2023 X 11048 GRAVOIS INDUSTRIAL 63128 FENTON TREATMENT BLOCKED MAIN NO2/1/2021 51 GREENDALE 63121 LEMAY TREATMENT BLOCKED MAIN NO10/31/2023 X 51 GREENDALE 63121 LEMAY TREATMENT BLOCKED MAIN NO9/2/2022 1090 GROBY 63130 LEMAY TREATMENT OVERCHARGED MAIN NO10/3/2023 X 1090 GROBY 63130 LEMAY TREATMENT OVERCHARGED MAIN NO10/13/2023 X 4360 HUMBER 63129 LEMAY TREATMENT BLOCKED MAIN NO4/27/2020 3676 ISOLDA 63074 COLDWATER TREATMENT BLOCKED MAIN NO11/26/2022 3676 ISOLDA 63074 COLDWATER TREATMENT BLOCKED MAIN NO12/3/2023 X 3676 ISOLDA 63074 COLDWATER TREATMENT BLOCKED MAIN NO6/13/2022 3404 ITASKA 63111 LEMAY TREATMENT OVERCHARGED MAIN NO7/28/2023 X 3404 ITASKA 63111 LEMAY TREATMENT OVERCHARGED MAIN NO5/20/2022 3417 ITASKA 63111 LEMAY TREATMENT OVERCHARGED MAIN NO8/4/2022 3417 ITASKA 63111 LEMAY TREATMENT OVERCHARGED MAIN NO4/19/2023 3417 ITASKA 63111 LEMAY TREATMENT OVERCHARGED MAIN NO4/19/2023 * 3417 ITASKA 63111 LEMAY TREATMENT OVERCHARGED MAIN NO11/1/2023 X 3417 ITASKA 63111 LEMAY TREATMENT OVERCHARGED MAIN NO6/21/2015 110 JEFFERSON 63122 LEMAY TREATMENT BLOCKED MAIN NO8/28/2015 110 JEFFERSON 63122 LEMAY TREATMENT BLOCKED MAIN NO11/8/2023 X 110 JEFFERSON 63122 LEMAY TREATMENT BLOCKED MAIN NO7/1/2023 X 7758 JEROME 63143 LEMAY TREATMENT OVERCHARGED MAIN NO8/30/2019 8513 KATHLEEN 63123 LEMAY TREATMENT OVERCHARGED MAIN NO11/21/2019 8513 KATHLEEN 63123 LEMAY TREATMENT BLOCKED MAIN NO12/16/2023 X 8513 KATHLEEN 63123 LEMAY TREATMENT BLOCKED MAIN NO12/25/2023 X 8513 KATHLEEN 63123 LEMAY TREATMENT BLOCKED MAIN NO 2023_12 Semi B1 backup Page 2 of 5 Metropolitan St. Louis Sewer District Semi-Annual Report Service Request Call Date Occurred During Current Reporting Period Street Number Street Name Zip Code Watershed/Treatment Plant Service Area Service Request Work Order Cause Discharge to Water of the US? (07/01/2023 - 12/31/2023, Effective Date 04/27/2012) Table B-1: Building Backup 7/14/2023 X 5005 KINGSHIGHWAY 63109 LEMAY TREATMENT OVERCHARGED MAIN NO7/28/2022 5007 KINGSHIGHWAY 63109 LEMAY TREATMENT OVERCHARGED MAIN NO7/14/2023 X 5007 KINGSHIGHWAY 63109 LEMAY TREATMENT OVERCHARGED MAIN NO6/9/2012 8014 LACLEDE STATION 63123 LEMAY TREATMENT BLOCKED MAIN NO11/29/2018 8014 LACLEDE STATION 63123 LEMAY TREATMENT BLOCKED MAIN NO9/2/2019 8014 LACLEDE STATION 63123 LEMAY TREATMENT BLOCKED MAIN NO12/7/2019 8014 LACLEDE STATION 63123 LEMAY TREATMENT BLOCKED MAIN NO1/2/2022 8014 LACLEDE STATION 63123 LEMAY TREATMENT BLOCKED MAIN NO11/8/2023 X 8014 LACLEDE STATION 63123 LEMAY TREATMENT BLOCKED MAIN NO12/29/2023 X 1923 LAKEMONT 63138 BISSELL TREATMENT BLOCKED MAIN NO12/22/2023 X 11168 LANDSEER 63136 BISSELL TREATMENT BLOCKED MAIN NO7/17/2020 9008 LINK 63114 LEMAY TREATMENT BLOCKED MAIN NO7/26/2022 9008 LINK 63114 LEMAY TREATMENT OVERCHARGED MAIN NO11/5/2023 X 9008 LINK 63114 LEMAY TREATMENT BLOCKED MAIN NO10/2/2023 X 1124 LUMIERE PLACE 63102 BISSELL TREATMENT BLOCKED MAIN NO5/24/2019 8543 MACKENZIE 63123 LEMAY TREATMENT OVERCHARGED MAIN NO8/18/2020 8543 MACKENZIE 63123 LEMAY TREATMENT OVERCHARGED MAIN NO4/15/2023 * 8543 MACKENZIE 63123 LEMAY TREATMENT SEWER SEPARATION FAILURE NO3/15/2023 342 MADISON 63119 LEMAY TREATMENT BLOCKED MAIN NO7/3/2023 X 342 MADISON 63119 LEMAY TREATMENT BLOCKED MAIN NO11/15/2023 X 9812 MANCHESTER 63119 LEMAY TREATMENT BLOCKED MAIN NO7/17/2023 X 6278 MARMADUKE 63139 LEMAY TREATMENT OVERCHARGED MAIN NO5/16/2023 7156 MARWINETTE 63116 LEMAY TREATMENT OVERCHARGED MAIN NO7/11/2023 X 7156 MARWINETTE 63116 LEMAY TREATMENT OVERCHARGED MAIN NO8/10/2022 5527 MAZE 63116 LEMAY TREATMENT OVERCHARGED MAIN NO6/18/2023 5527 MAZE 63116 LEMAY TREATMENT OVERCHARGED MAIN NO7/31/2023 X 5527 MAZE 63116 LEMAY TREATMENT OVERCHARGED MAIN NO12/20/2023 X 10255 MEADOWOOD 63114 COLDWATER TREATMENT BLOCKED MAIN NO10/17/2023 X 830 MERAMEC STATION 63088 GRAND GLAIZE TREATMENT BLOCKED MAIN NO11/30/2023 X 3227 MILISSA 63125 LEMAY TREATMENT BLOCKED MAIN NO7/3/2023 X 6421 MINNESOTA 63111 LEMAY TREATMENT OVERCHARGED MAIN NO7/3/2023 X 6421 MINNESOTA 63111 LEMAY TREATMENT OVERCHARGED MAIN NO12/26/2023 X 10219 MONARCH 63136 BISSELL TREATMENT BLOCKED MAIN NO9/12/2023 X 7413 PARKWOOD 63116 LEMAY TREATMENT OVERCHARGED MAIN NO11/7/2023 X 8860 PERSHALL 63042 COLDWATER TREATMENT BLOCKED MAIN NO9/12/2023 X 3084 POSTPORT 63043 MISSOURI RIVER TREATMENT BLOCKED MAIN NO11/10/2017 3087 POSTPORT 63043 MISSOURI RIVER TREATMENT BLOCKED MAIN NO9/12/2023 X 3087 POSTPORT 63043 MISSOURI RIVER TREATMENT BLOCKED MAIN NO11/15/2022 3091 POSTPORT 63043 MISSOURI RIVER TREATMENT BLOCKED MAIN NO9/12/2023 X 3091 POSTPORT 63043 MISSOURI RIVER TREATMENT BLOCKED MAIN NO11/10/2017 3095 POSTPORT 63043 MISSOURI RIVER TREATMENT BLOCKED MAIN NO 2023_12 Semi B1 backup Page 3 of 5 Metropolitan St. Louis Sewer District Semi-Annual Report Service Request Call Date Occurred During Current Reporting Period Street Number Street Name Zip Code Watershed/Treatment Plant Service Area Service Request Work Order Cause Discharge to Water of the US? (07/01/2023 - 12/31/2023, Effective Date 04/27/2012) Table B-1: Building Backup 11/15/2022 3095 POSTPORT 63043 MISSOURI RIVER TREATMENT BLOCKED MAIN NO9/12/2023 X 3095 POSTPORT 63043 MISSOURI RIVER TREATMENT BLOCKED MAIN NO7/29/2023 X 5232 RAYMOND 63113 LEMAY TREATMENT OVERCHARGED MAIN NO8/15/2016 709 REED 63125 LEMAY TREATMENT OVERCHARGED MAIN NO5/15/2023 * 709 REED 63125 LEMAY TREATMENT OVERCHARGED MAIN NO5/17/2023 4210 SAN FRANCISCO 63115 BISSELL TREATMENT OVERCHARGED MAIN NO7/1/2023 X 4210 SAN FRANCISCO 63115 BISSELL TREATMENT OVERCHARGED MAIN NO8/26/2023 X 4815 SAN FRANCISCO 63115 BISSELL TREATMENT BLOCKED MAIN NO7/10/2023 X 2207 SCOTT 63103 BISSELL TREATMENT BLOCKED MAIN NO7/10/2023 X 2215 SCOTT 63103 BISSELL TREATMENT BLOCKED MAIN NO11/24/2023 X 3 SHARDUE 63141 LEMAY TREATMENT BLOCKED MAIN NO5/26/2019 7206 SHELLBURNE 63123 LEMAY TREATMENT OVERCHARGED MAIN NO1/10/2020 7206 SHELLBURNE 63123 LEMAY TREATMENT OVERCHARGED MAIN NO12/24/2023 X 7206 SHELLBURNE 63123 LEMAY TREATMENT BLOCKED MAIN NO7/16/2020 2901 SHORES 63125 LEMAY TREATMENT OVERCHARGED MAIN NO8/9/2020 2901 SHORES 63125 LEMAY TREATMENT OVERCHARGED MAIN NO8/15/2020 2901 SHORES 63125 LEMAY TREATMENT OVERCHARGED MAIN NO11/21/2020 2901 SHORES 63125 LEMAY TREATMENT BLOCKED MAIN NO11/29/2020 2901 SHORES 63125 LEMAY TREATMENT BLOCKED MAIN NO5/13/2023 2901 SHORES 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/17/2023 X 2901 SHORES 63125 LEMAY TREATMENT BLOCKED MAIN NO11/6/2023 X 11836 SMOKE VALLEY 63043 MISSOURI RIVER TREATMENT BLOCKED MAIN NO7/17/2023 X 11405 ST CHARLES ROCK 63044 COLDWATER TREATMENT BLOCKED MAIN NO5/23/2019 3640 STEINS 63116 LEMAY TREATMENT OVERCHARGED MAIN NO7/18/2023 X 3640 STEINS 63116 LEMAY TREATMENT OVERCHARGED MAIN NO12/29/2023 X 1300 SUSANAIRE 63146 MISSOURI RIVER TREATMENT BLOCKED MAIN NO6/3/2020 4708 TARLTON 63128 MERAMEC TREATMENT BLOCKED MAIN NO10/7/2023 X 4708 TARLTON 63128 MERAMEC TREATMENT BLOCKED MAIN NO10/25/2023 X 306 TAYLOR 63042 COLDWATER TREATMENT BLOCKED MAIN NO6/20/2017 4700 TESSON 63116 LEMAY TREATMENT OVERCHARGED MAIN NO5/23/2019 4700 TESSON 63116 LEMAY TREATMENT OVERCHARGED MAIN NO8/30/2019 4700 TESSON 63116 LEMAY TREATMENT OVERCHARGED MAIN NO6/30/2020 4700 TESSON 63116 LEMAY TREATMENT OVERCHARGED MAIN NO8/15/2020 4700 TESSON 63116 LEMAY TREATMENT OVERCHARGED MAIN NO5/18/2023 * 4700 TESSON 63116 LEMAY TREATMENT SEWER SEPARATION FAILURE NO7/23/2023 X 4700 TESSON 63116 LEMAY TREATMENT SEWER SEPARATION FAILURE NO10/11/2023 X 4608 TOWER GROVE 63110 BISSELL TREATMENT BLOCKED MAIN NO12/26/2023 X 508 TWEED 63125 LEMAY TREATMENT BLOCKED MAIN NO10/3/2023 X 6751 VERNON 63130 LEMAY TREATMENT OVERCHARGED MAIN NO6/17/2013 3637 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3637 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO 2023_12 Semi B1 backup Page 4 of 5 Metropolitan St. Louis Sewer District Semi-Annual Report Service Request Call Date Occurred During Current Reporting Period Street Number Street Name Zip Code Watershed/Treatment Plant Service Area Service Request Work Order Cause Discharge to Water of the US? (07/01/2023 - 12/31/2023, Effective Date 04/27/2012) Table B-1: Building Backup 6/17/2013 3639 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3639 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO6/17/2013 3641 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3641 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3643 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3647 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3649 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3651 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3653 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO6/20/2015 3657 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO6/23/2015 3657 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO8/15/2016 3657 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3657 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3659 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3661 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO8/15/2016 3663 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO1/10/2020 3663 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3663 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO8/16/2016 3675 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3675 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO8/15/2016 3677 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3677 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3679 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO8/16/2016 3683 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/6/2023 X 3683 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO7/5/2023 X 3685 VESCOVO 63125 LEMAY TREATMENT OVERCHARGED MAIN NO8/26/2019 204 VEST 63088 GRAND GLAIZE TREATMENT OVERCHARGED MAIN NO7/21/2023 X 204 VEST 63088 GRAND GLAIZE TREATMENT BLOCKED MAIN NO8/7/2023 X 4111 VON TALGE 63128 MERAMEC TREATMENT BLOCKED MAIN NO5/13/2023 6052 WATERMAN 63112 LEMAY TREATMENT OVERCHARGED MAIN NO10/28/2023 X 6052 WATERMAN 63112 LEMAY TREATMENT OVERCHARGED MAIN NO10/15/2023 X 4622 WEBER TERRACE 63123 LEMAY TREATMENT BLOCKED MAIN NO8/10/2023 X 12965 WHITECLIFF 63033 COLDWATER TREATMENT BLOCKED MAIN NO5/15/2023 * 10094 WINDING RIDGE 63124 LEMAY TREATMENT SEWER SEPARATION FAILURE NO100TOTAL BUILDING BACKUPS DURING THE REPORTING PERIOD 2023_12 Semi B1 backup Page 5 of 5 Metropolitan St. Louis Sewer District Semi-Annual Report – July 1 to December 31, 2023 APPENDIX C: SANITARY SEWER OVERFLOWS SANITARY SEWER OVERFLOWS Attached and Spreadsheet File Provided on Enclosed Disk Metropolitan St. Louis Sewer District Semi-Annual Report Table C-1: Sanitary Sewer Overflows 07/01/2023 - 12/31/2023 Work Order Start Date Watershed/ Treatment Plant Service Area Service Address Location Description Facility Type Estimated Volume (gallons) Reason / Cause Time To Commence Investigation (day hh:mm) Time To Correct and/or Cleanup (day hh:mm) 07/11/23 LEMAY TREATMENT 5 WINDING BROOK LN, 63124 GIS-1637947 MANHOLE 100 BLOCKED WITH GRIT 01:29 01:05 07/11/23 MISSOURI RIVER TREATMENT 1602 RIDGE BEND DR, 63038 E64832 PUMP STATION 100 EQUIPMENT FAILURE 00:00 21:50 07/17/23 MISSOURI RIVER TREATMENT 16885 CRYSTAL SPRINGS DR, 63005 E11229 PUMP STATION 6,000 BROKEN PIPE 00:00 03:15 07/19/23 GRAND GLAIZE TREATMENT 1000 WEIDMAN RD, 63017 GIS-2513744 GRAVITY MAIN 100 BLOCKED WITH DEBRIS 00:00 19:23 07/19/23 GRAND GLAIZE TREATMENT 1004 WEIDMAN RD, 63017 GIS-2513744 GRAVITY MAIN 50 BLOCKED WITH DEBRIS 00:00 19:23 07/21/23 COLDWATER TREATMENT 6620 BLOSSOM VIEW DR, 63033 GIS-2340026 GRAVITY MAIN 30 BLOCKED WITH ROOTS 00:21 10:20 07/30/23 LEMAY TREATMENT 9330 MANCHESTER RD, 63119 GIS-1554998 MANHOLE 80 BLOCKED WITH DEBRIS 01:54 15:20 08/05/23 LEMAY TREATMENT 9262 EDDIE AND PARK RD, 63126 GIS-1605156 MANHOLE 300 BLOCKED WITH DEBRIS 01:37 01:30 08/06/23 GRAND GLAIZE TREATMENT 148 CUMBERLAND PARK CT, 63011 GIS-14838717 GRAVITY MAIN 90 BLOCKED WITH DEBRIS 01:30 12:00 08/14/23 MERAMEC TREATMENT 4319 BUTLER HILL RD, 63128 GIS-1617313 MANHOLE 300 BLOCKED WITH GREASE 01:54 14:30 08/16/23 LEMAY TREATMENT 555 N NEW BALLAS RD, 63141 GIS-1531593 MANHOLE 100 BLOCKED WITH GREASE 00:00 20:01 08/25/23 FENTON TREATMENT 1488 PREMIO DR, 63026 E10490 PUMP STATION 100 BROKEN PIPE 00:00 01:36 08/31/23 MERAMEC TREATMENT 2535 OAKMONT TERRACE DR, 63129 GIS-1615884 MANHOLE 150 BLOCKED WITH DEBRIS 00:24 02:30 09/01/23 MISSOURI RIVER TREATMENT 5 CHESTERFIELD LAKES RD, 63005 E69106 PUMP STATION 1,000 VANDALISM BREAKAGE 00:00 06:00 09/06/23 LEMAY TREATMENT 8777 DEL VISTA DR, 63126 GIS-1611743 MANHOLE 160 BLOCKED WITH GRIT 04:48 01:00 09/07/23 LEMAY TREATMENT 810 MARCO DR, 63122 E10645 PUMP STATION 25,000 BROKEN PIPE 00:00 22 DAY 05:30 09/09/23 LEMAY TREATMENT 810 MARCO DR, 63122 E11952 PUMP STATION 4,000 BROKEN PIPE 00:00 20 DAY 15:55 09/09/23 MISSOURI RIVER TREATMENT 108 LADUE GLEN CT, 63017 GIS-1479708 MANHOLE 3,200 BLOCKED WITH DEBRIS 01:17 1 DAY 19:10 09/13/23 LEMAY TREATMENT 7665 GENERAL GRANT CT, 63123 GIS-2464658 GRAVITY MAIN 200 BROKEN PIPE 00:00 5 DAY 00:20 2023_12 Semi C1 known SSO Page 1 of 4 Metropolitan St. Louis Sewer District Semi-Annual Report Table C-1: Sanitary Sewer Overflows 07/01/2023 - 12/31/2023 Work Order Start Date Watershed/ Treatment Plant Service Area Service Address Location Description Facility Type Estimated Volume (gallons) Reason / Cause Time To Commence Investigation (day hh:mm) Time To Correct and/or Cleanup (day hh:mm) 09/13/23 MERAMEC TREATMENT 5775 LILAC TRAILS DR, 63128 GIS-1619495 MANHOLE 60 BLOCKED WITH ROOTS 01:33 01:30 09/14/23 LEMAY TREATMENT 2724 S LINDBERGH BLVD, 63131 GIS-1570890 MANHOLE 100 BLOCKED WITH ROOTS 01:30 1 DAY 04:00 09/14/23 GRAND GLAIZE TREATMENT 63 OAK HILL DR, 63021 GIS-1587833 MANHOLE 100 BLOCKED WITH DEBRIS 02:58 03:45 09/14/23 FENTON TREATMENT 11048 GRAVOIS INDUSTRIAL CT, 63128 GIS-2531993 GRAVITY MAIN 70 BLOCKED WITH DEBRIS 02:04 02:30 09/15/23 FENTON TREATMENT 11085 GRAVOIS INDUSTRIAL CT, 63128 GIS-2531993 GRAVITY MAIN 35 BLOCKED WITH DEBRIS 03:42 00:25 09/17/23 LEMAY TREATMENT 24 FAIR OAKS DR, 63124 GIS-1481829 MANHOLE 30 BLOCKED WITH DEBRIS 00:30 01:45 09/26/23 MISSOURI RIVER TREATMENT 16782 WILLS TRACE ST, 63005 E69120 PUMP STATION 100 BROKEN PIPE 00:00 05:42 09/28/23 COLDWATER TREATMENT 13530 OLD HALLS FERRY RD, 63033 GIS-2535559 GRAVITY MAIN 1,100 BROKEN PIPE 00:00 07:59 10/02/23 FENTON TREATMENT 211 S OLD HIGHWAY 141, 63026 GIS-2479849 GRAVITY MAIN 400 BLOCKED WITH DEBRIS 00:00 1 DAY 22:51 10/05/23 FENTON TREATMENT 1488 PREMIO DR, 63026 E10658 PUMP STATION 2,000 BROKEN PIPE 00:15 00:00 10/05/23 MERAMEC TREATMENT 5801 SORREL TREE CT, 63129 GIS-1623125 MANHOLE 40 BLOCKED WITH DEBRIS 00:48 03:20 10/09/23 LEMAY TREATMENT 5823 OAK FOREST LN, 63128 E10657 PUMP STATION 2,200 BROKEN PIPE 00:30 04:30 10/10/23 MISSOURI RIVER TREATMENT 2504 PEPPERMILL LAKE CT, 63005 E11843 PUMP STATION 3,100 VANDALISM BREAKAGE 01:43 3 DAY 04:40 10/12/23 MERAMEC TREATMENT 2800 BLACKFOREST DR, 63129 GIS-1622839 MANHOLE 1,540 BLOCKED WITH DEBRIS 01:11 1 DAY 03:00 10/19/23 LEMAY TREATMENT 8570 WATSON RD, 63119 GIS-1584942 MANHOLE 920 BLOCKED WITH GREASE 00:40 03:30 10/19/23 BISSELL TREATMENT 2575 REDMAN RD, 63136 GIS-2342862 GRAVITY MAIN 650 BROKEN PIPE 00:50 1 DAY 03:40 10/20/23 MISSOURI RIVER TREATMENT 15043 MANOR KNOLL DR, 63017 GIS-1572864 MANHOLE 140 BLOCKED WITH DEBRIS 00:30 01:30 10/21/23 COLDWATER TREATMENT 7551 HAZELCREST DR, 63042 GIS-1496783 MANHOLE 460 BLOCKED WITH GREASE 02:00 01:50 10/26/23 MERAMEC TREATMENT 3085 CAMBRIDGE VIEW CT, 63129 GIS-1612567 MANHOLE 430 BLOCKED WITH ROOTS 01:00 3 DAY 07:00 2023_12 Semi C1 known SSO Page 2 of 4 Metropolitan St. Louis Sewer District Semi-Annual Report Table C-1: Sanitary Sewer Overflows 07/01/2023 - 12/31/2023 Work Order Start Date Watershed/ Treatment Plant Service Area Service Address Location Description Facility Type Estimated Volume (gallons) Reason / Cause Time To Commence Investigation (day hh:mm) Time To Correct and/or Cleanup (day hh:mm) 10/27/23 BISSELL TREATMENT 1542 NESBIT DR, 63136 GIS-2355165 GRAVITY MAIN 310 BLOCKED WITH GREASE 01:40 20:00 11/01/23 MISSOURI RIVER TREATMENT 10827 MIDLAND BLVD, 63114 GIS-1529942 MANHOLE 240 VANDALISM DUMPING 01:42 07:45 11/03/23 LEMAY TREATMENT 7800 FORSYTH BLVD, 63105 GIS-2395314 GRAVITY MAIN 180 BLOCKED WITH GREASE 00:30 00:45 11/04/23 MERAMEC TREATMENT 7193 DECKSIDE DR, 63129 GIS-1624075 MANHOLE 220 BLOCKED WITH ROOTS 01:03 01:30 11/04/23 MISSOURI RIVER TREATMENT 2150 VILLAGE GREEN PKWY, 63017 GIS-2418555 GRAVITY MAIN 420 BLOCKED WITH DEBRIS 01:20 02:30 11/05/23 LEMAY TREATMENT 9201 CHERRY BROOK LN, 63126 GIS-1611623 MANHOLE 160 BLOCKED WITH ROOTS 00:35 01:00 11/07/23 LEMAY TREATMENT 113 W LOCKWOOD AVE, 63119 GIS-1581689 MANHOLE 200 BLOCKED WITH GREASE 00:12 2 DAY 02:15 11/11/23 COLDWATER TREATMENT 8327 MIDWOOD AVE, 63134 GIS-2349949 GRAVITY MAIN 50 BLOCKED WITH DEBRIS 00:08 1 DAY 00:00 11/11/23 GRAND GLAIZE TREATMENT 1092 MANORS WAY, 63017 GIS-1565557 MANHOLE 200 BLOCKED WITH DEBRIS 00:10 4 DAY 18:47 11/12/23 GRAND GLAIZE TREATMENT 1092 MANORS WAY, 63017 GIS-1565556 MANHOLE 100 BLOCKED WITH DEBRIS 00:00 4 DAY 00:02 11/13/23 GRAND GLAIZE TREATMENT 1103 SHEFFIELD MANOR CT, 63017 GIS-2418226 GRAVITY MAIN 40 BLOCKED WITH DEBRIS 01:40 02:00 11/13/23 GRAND GLAIZE TREATMENT 1017 DEVONWORTH MANOR WAY, 63017 GIS-1552304 MANHOLE 820 BLOCKED WITH DEBRIS 00:50 09:30 11/16/23 FENTON TREATMENT 27 BROOKWOOD DR, 63026 GIS-1618084 MANHOLE 1,336 BLOCKED WITH ROOTS 01:51 1 DAY 20:30 11/20/23 MISSOURI RIVER TREATMENT 3180 BRISTOLHALL DR, 63043 GIS-2361665 GRAVITY MAIN 586 BLOCKED WITH GRIT 00:24 1 DAY 21:40 11/23/23 FENTON TREATMENT 12473 ROBYN RD, 63127 GIS-1604217 MANHOLE 100 BLOCKED WITH ROOTS 01:42 02:00 11/29/23 MISSOURI RIVER TREATMENT 3180 BRISTOLHALL DR, 63043 GIS-2520007 GRAVITY MAIN 200 BROKEN PIPE 01:00 09:20 12/01/23 MISSOURI RIVER TREATMENT 36 FOREST CLUB DR, 63005 GIS-1558768 MANHOLE 300 BLOCKED WITH GREASE 01:13 01:30 12/03/23 COLDWATER TREATMENT 315 HOWDERSHELL RD, 63031 GIS-1502143 MANHOLE 900 VANDALISM DUMPING 01:40 02:00 12/05/23 MISSOURI RIVER TREATMENT 14220 COOPERSTOWN DR, 63017 GIS-1481359 MANHOLE 130 BLOCKED WITH DEBRIS 00:48 01:40 2023_12 Semi C1 known SSO Page 3 of 4 Metropolitan St. Louis Sewer District Semi-Annual Report Table C-1: Sanitary Sewer Overflows 07/01/2023 - 12/31/2023 Work Order Start Date Watershed/ Treatment Plant Service Area Service Address Location Description Facility Type Estimated Volume (gallons) Reason / Cause Time To Commence Investigation (day hh:mm) Time To Correct and/or Cleanup (day hh:mm) 12/06/23 MISSOURI RIVER TREATMENT 12 CROWNHILL LN, 63005 GIS-1573443 MANHOLE 50 BLOCKED WITH GRIT 01:22 02:30 12/07/23 LEMAY TREATMENT 366 S KIRKWOOD RD, 63122 GIS-2515503 GRAVITY MAIN 200 BLOCKED WITH GREASE 00:57 02:00 12/08/23 LEMAY TREATMENT 7626 DALE AVE, 63117 GIS-2513414 GRAVITY MAIN 70 BLOCKED WITH DEBRIS 01:59 01:00 12/09/23 LEMAY TREATMENT 6901 MACKENZIE RD, 63123 GIS-1584329 MANHOLE 1,450 BLOCKED WITH DEBRIS 03:20 1 DAY 00:00 12/12/23 COLDWATER TREATMENT 14431 SOHO DR, 63034 GIS-1492107 MANHOLE 430 BLOCKED WITH DEBRIS 00:39 07:50 12/12/23 GRAND GLAIZE TREATMENT 2650 OLD DOUGHERTY FERRY RD, 63122 GIS-1635098 MANHOLE 50 BLOCKED WITH DEBRIS 01:05 1 DAY 02:45 12/12/23 MERAMEC TREATMENT 4984 BRUNSTON DR, 63128 GIS-1615573 MANHOLE 80 BLOCKED WITH ROOTS 02:00 01:45 12/14/23 LEMAY TREATMENT 1405 S HANLEY RD, 63144 GIS-1629634 MANHOLE 50 BLOCKED WITH GREASE 00:45 1 DAY 03:15 12/20/23 MISSOURI RIVER TREATMENT 2475 ROCK ISLAND BLVD, 63043 GIS-1479705 MANHOLE 700 BLOCKED WITH DEBRIS 00:29 2 DAY 02:10 12/21/23 BISSELL TREATMENT 10100 CASTLE DR, 63136 GIS-1510803 MANHOLE 50 BLOCKED WITH DEBRIS 01:37 16:45 12/23/23 GRAND GLAIZE TREATMENT 204 SUGAR CREEK RIDGE DR, 63122 GIS-2448213 GRAVITY MAIN 50 BLOCKED WITH DEBRIS 01:18 16:15 12/24/23 MERAMEC TREATMENT 2844 BLACKFOREST DR, 63129 GIS-1622831 MANHOLE 220 BLOCKED WITH GREASE 01:20 00:30 12/26/23 MISSOURI RIVER TREATMENT 16909 BORDEAUX ESTATES CT, 63040 E64844 PUMP STATION 500 BROKEN PIPE 00:14 02:45 2023_12 Semi C1 known SSO Page 4 of 4