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HomeMy WebLinkAbout5. MWRDGC Inflow/Infiltration RuleMount Prospect I ? LL i INTEROFFICE MEMORANDUM TO: VILLAGE MANAGER MICHAEL E. JANONIS FROM: DIRECTOR OF PUBLIC WORKS DATE: APRIL 4, 2014 SUBJ: MWRDGC INFLOW/ INFILTRATION RULE The purpose of this memo is to highlight the requirements of the Inflow and Infiltration Rule soon to be enacted by the Metropolitan Water Reclamation District of Greater Chicago (MWRDGC) in ordinance form. This new rule will replace the current inflow and infiltration plan known as ICAP. ICAP is an acronym for Infiltration /Inflow Corrective Action Plan. The ICAP program has been in place since 1991. The Inflow and Infiltration Rule only applies to separate sanitary sewer systems tributary to the MWRDGC. Attachment A depicts the separate sanitary sewer areas in the Village -owned wastewater collection system. Infiltration is defined as sources of groundwater flow, which may be prevalent year- round, and rainfall dependent flow, which is prevalent during and shortly after rain events. Generally, infiltration is facilitated by cracks and separations in sewer pipes and manhole structures. Inflow is defined as the extraneous flow that enters the sanitary sewer systems quickly through direct connections to the sewers. Typical types of direct connections where storm water can enter the sanitary sewer include open -pick manhole covers, surface or yard drains, roof downspouts, clear water sump pump connections, footing tile connections, or private service connection cleanouts with missing caps. Background A comprehensive effort was initiated during the 1970s and early 1980s by the Metropolitan Sanitary District of Greater Chicago, now referred to as the Metropolitan Water Reclamation District of Greater Chicago, or MWRDGC. This comprehensive program was designed to correct deficiencies in a separate sanitary sewer system only. All entities serviced by the MWRDGC having jurisdiction over the separate sanitary sewer system were required to implement programs for the elimination of extraneous storm and groundwater flows in the sanitary sewer system. In January 1974, the MWRDGC completed a report entitled "Infiltration Flow Analysis, Upper Des Plaines Service Basin ". That report concluded that the sewer systems tributary to the planned O' Hare (Kirie) Water Reclamation Plant were subject to excessive infiltration and inflow. As part of the District's system, the Village, along with all other municipalities being served by the District, in 1977 performed a Sewer System Evaluation Study (SSES). This SSES consisted of flow monitoring, Mount Prospect Public Works Department Page 2 of 6 MWRDGC Inflow /Infiltration Rule April 4, 2014 manhole inspections, smoke testing, dye water flooding and internal sewer televising. These programs were designed to alleviate widespread occurrences of basement flooding and also reduce the overloading of separate sanitary sewer systems and MWRDGC interceptors and treatment plants. During the 1980s, a series of meetings between elected local officials and representatives of the MWRDGC, Illinois Environmental Protection Agency (IEPA), and the United States Environmental Protection Agency (USEPA) were held on the matter of sewer rehabilitation. These meetings were a response to continued flooding problems throughout the region. The outcome of the meetings was a "Sewer Summit Agreement" which established guidelines and a schedule for achieving final compliance with the sewer rehabilitation requirements. This Sewer Summit Agreement gave MWRDGC member communities two compliance options. One option was to allow the member community to reduce sanitary sewer flow rates to 150 gallons per capita per day (150 gpcpd). At the time, this was the estimated water usage that a person used each day by means of cooking, cleaning, or bathing. Under this option, there is only a very small allowance for clear water which means the sanitary sewer system would have to be kept void of any defects or connections that would allow clear water to enter the system. 150gpcpd Option a. Average daily wet weather flow shall not exceed 150 gpcpd or optionally, documented water usage plus allowable infiltration of 500 gallons per inch diameter -mile of sewer per day. b. Elimination of basement sewage backups and other adverse surcharging conditions that cause health hazards or financial losses. The other option was to allow member communities to elect the Infiltration /Inflow Corrective Action Plan (ICAP). This option allowed communities to inspect their sanitary sewer system and then correct all deficiencies or illegal connections found in a way that was most cost effective to the community. Cost effective corrections were defined as defects that were cheaper to fix than the cost of transporting and treating the clear water they added t the sanitary sewer system. With the ICAP option came flow monitoring. Once all defects were repaired under the ICAP option, member communities were then required to submit flow rates of the sanitary sewer system to the MWRDGC. It was at this time, the MWRDGC established an "ICAP Post Rehab Flow Rate ". Communities that selected the ICAP option then had to keep their sanitary sewer flows below the new established rate. 2. ICAP Option a. Under this option, each tributary community must perform a program for incremental correction of excessive I &I as determined from a cost effectiveness analysis prepared by the tributary community. b. The communities following the ICAP alternative must meet the following criteria: 1. All I &I that is determined to be excessive by the cost effectiveness analysis shall be eliminated. 2. Completion of such additional work as may be required as a result of a Sewer System Compliance Conference. The Village, and most other MWRDGC member agencies selected the ICAP option. Page 3 of 6 MWRDGC Inflow /Infiltration Rule April 4, 2014 During the 1980s, a Sanitary Sewer Evaluation Survey was performed. This work involved inspecting a large portion of the Village's sanitary sewer system. Manhole inspections dye testing, closed circuit televising of main line sewers, smoke testing, and private building inspections were performed. Almost $3,000,000 of public sewer grouting, re- lining, and spot relays work was performed. In addition, over 600 private clear water sump pump connections were removed from the Village's sanitary sewer system. By the early 1990s, the rehabilitation work had been completed and flow monitoring of the sanitary sewer system was initiated. After monitoring, the MWRDGC set the Village's Post Rehabilitation Flow Rate at 673 gpcpd (gallons per capita per day). Subsequently, the Village entered an Annual Long Term Operation and Maintenance Agreements with the MWRDGC that stipulates that the Village continue to perform all inspections of the sanitary sewer system and perform corrective work on all defects found in order to keep our sanitary sewer flows below 673 gpcpd. The scope of maintenance and corrective work includes cured in place pipe (CIPP) lining, spot relay work, manhole reconstruction, manhole inspections, sewer televising, building inspections, flow monitoring, dye -water testing, smoke testing, as well as lift/relief station maintenance. Notably, during formulation of the ICAP program, the MWRDGC determined that the elimination of direct footing tile connections was not cost effective. It made better sense to transport and treat water generated by this inflow source than it did to eliminate it. Water from direct footing tile connections was considered by the MWRDGC to be a reasonable amount of clear water that their system could handle. Because of this decision, the Village does not require home owners to disconnect direct footing tile connections. The Village of Mount Prospect is, and continuously has been, in full compliance with all ICAP and Long Term Maintenance Program requirements. Our current flow rate is 173 gpcpd (ICAP Post Rehab Flow Rate is 673 gpcpd). Inflow /Infiltration Rule Recently, MWRDGC renewed National Pollutant Discharge Elimination System permits for several of their wastewater treatment plants. These permits are necessary because the plants discharge treated effluent and untreated by -pass flows to local waterways. As part of this renewal process, IEPA has imposed a special condition in the NPDES permits that requires the system owners to implement measures in addition to the Sewer Summit Agreement if excessive wet weather flow causes or contributes to basement backup or sanitary sewer overflows (SSOs). Explaining this stipulation, IEPA has expressed concern about the increase in wet weather flows to MWRDGC treatment plants, the frequency of sanitary sewer overflows (including treatment plant by- passes), and volume basement back -ups throughout the MWRDGC service area. In response, the MWRDGC formed an Advisory Technical Panel (ATP) to address these IEPA's concerns. The ATP was formulated as a collaborative and participative means to involve all stakeholders impacted by the new NPDES permit requirements. The ATP was comprised of representatives from the United States Environmental Protection Agency (USEPA), IEPA, Council of Government (COGs), local sanitary districts, utility companies, consulting engineers and MWRDGC staff. Page 4 of 6 MWRDGC Inflow /Infiltration Rule April 4, 2014 ATP held bi- monthly /monthly meetings over the last two years and has developed an inflow and infiltration control program to address the regulatory requirements. This program has been commonly referred to as the Inflow and Infiltration Rule. The key elements of this rule are summarized below: Applicability All tributary municipalities that own and /or operate a sanitary sewer system that discharges directly and /or indirectly into MWRD facilities. Presently, there are 125 separate sewer agencies affected by this rule. Scope & Goals • Comply with the MWRDGC NPDES Permit. • Eliminate basement backups (BBs). • Eliminate waterway pollution through sanitary sewer overflows (SSOs). • Work with municipalities on a cost - effective approach to 1/1 reduction. Short Term Plan • To be completed within the first 5 years: — Public Sector Condition Assessment and Rehabilitation. — Development of Private Sector Program by each municipality. — Development of Long Term O &M Program by each municipality. Public Sector Condition Assessment • Assessment of medium to high risk public sewer system condition through inspections. • Prioritization of areas with SSOs, BBs and surcharging. • Plan for correcting identified defects, including a schedule and funding approach. • Removal of illegal downspout connections. • Prior documented inspections may be credited. Private Sector Program • Program to be developed by each tributary municipality within 5 years. • Municipalities with existing programs should submit for review within 6 months. • Program should address: — Areas to inspect for 1/1 source identification. — 1/1 sources that require immediate or long term correction. — Enactment of local ordinances and enforcement. Long Term O &M Program • Implemented no later than 5 years following effective date of ordinance (May 2014). • Implementation of the Private Sector Program. • Implementation of the Public Sector Program. — Continual sewer inspection, maintenance, cleaning and rehabilitation. — Proactive Program addressing sewers on a prioritized basis. — Emergency Program addressing BBs and SSOs. — GIS Mapping and Asset Management. — Prioritized Capital Improvement Plan (CIP). — Funding plan for O &M, rehabilitation and replacement. Annual Reporting • Report progress toward completing the Short Term Plan. • Report completed work under the Long Term O &M Program: Page 5 of 6 MWRDGC Inflow /Infiltration Rule April 4, 2014 — Includes all inspection, cleaning, maintenance and rehabilitation work completed. — Summary of all public and private sector SSOs and BBs. System Analysis • MWRD Identify /allocate MWRD interceptor capacity. — Develop local storage standards /regulations and guidelines. • Municipal Sewer System and ATP — Develop performance metrics to define success. — Develop percentage of system to be inspected /cleaned /rehabilitated annually. Enforcement • MWRD — Establish incentives /enforcement actions for compliance with the Short Term Plan, Long Term O &M Program and submittal of the Annual Report. — Qualifications for funding assistance. — Excess flow charge. — Non - compliance status can be forwarded to IEPA for Show Cause action and Consent Decree. • Municipality — Enact and enforce ordinance(s) to address non - compliance with the Private Sector Program. — Incentive program(s) to encourage compliance. Funding • The MWRD may provide funding options to the municipalities for their 1/1 removal subject to Public Act 90 -0690 as amended from time to time. • The IEPA has SRF funding available to all communities within the MWRD corporate limits. • Municipalities can fund their Short Term Plan and Long Term O &M Program via local sewer service fees or other funding options. Schedule • April 2014 — MWRD Board of Commissioners Study Session • April 2014 — Adoption • May 1, 2014 — Effective Date • ATP will continue to meet to develop technical guidance Village Impacts It is the opinion of staff that the Village's existing sewer maintenance and capital improvement programs satisfy the new Inflow and Infiltration Rule requirements to a very large extent. However, we note the following areas of concern: The emphasis of maintenance programs will change from the post - rehabilitation flow rate (673 gpcpd) to basement back -ups. Since experience has indicated that Village sewer systems are reactive to severe wet weather, this change in focus could alter scheduling and prioritization of maintenance and capital improvements programs. There will be a need to continue commitment to existing funding levels for sewer system operation and maintenance. Page 6 of 6 MWRDGC Inflow /Infiltration Rule April 4, 2014 In the long term (5 years), there will be an increased emphasis on addressing inflow and infiltration emanating from private sector sources. Specifically, direct footing tile connections and poorly maintained sewer service laterals. Also in the long term (5 years), there will likely be a new focus on the concept of life -cycle replacement for sewer systems. For example, assuming a sewer pipe has a 50 -year life, a municipality may look to replace 2% of sewer pipe each year. Such a plan could impact capital improvements funding levels. Finally, it should be noted that the historical roles of both the MWRDGC and IEPA are likely to change. That is, staff anticipates that both will assume a more authoritative stature. As a result, non- compliance, or general failure of the Inflow and Infiltration Rule, could result in substantive enforcement action such as a consent decree. I would greatly appreciate it if this matter could be placed on the agenda for the April 8, 2014 Committee of the Whole meeting. Appropriate staff will be on hand to provide additional details and facilitate discussion of this subject. Cc: Deputy Director of Public Works Jason Leib Water /Sewer Superintendent Matt Overeem SEPARATE SANITARY ATTACHMENT A ee SEWER BASINS --- AED -RED 4W G4EN REEd� sm SS62 a SS61 S S : ssil Ja 5Wl JS� r7l CS631 sl o SS16 .—J SS45 , ­ -- SS42 SS37