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87-119 B .. CITY OF CHANHASSEN CARVER AND HENNEPIN COUNTIES, MINNESOTA DATE: November 16, 1987 RESOLUTION NO: 87-119B e MOTION BY: Horn SECONDED BY: Hamilton A RESOLUTION AMENDING THE COMPREHENSIVE PLAN WHEREAS, the City, in accordance with the Metropolitan Land Planning Act, adopted the Comprehensive Plan on April 19, 1982; and amended said plan on March 3, 1986; and WHEREAS, the City, in comformance with the Lake Ann Sewer Facility Agreement, must revise its Comprehensive Sewer Plan to provide a description of on-site sewage treatment regulations and provide policies and ~rogram descriptions for infiltration and inflow reduction; and WHEREAS, a public hearing was held on said Comprehensive Plan amendment on November 4, 1987 by the Planning Commission; and WHEREAS, the City Council considered said Comprehensive Plan amendment on November 16, 1987; and WHEREAS, the City, in accordance with the Metropolitan Land Planning Act and the Metropolitan Council Guidelines for Reviewing Local Comprehensive Plan Amendments, has determined that the amendment is consistent with the goals and policies of the Comprehensive Plan and its land use element; and e WHEREAS, the amendment has been determined by the Metropolitan Council to be in conformity with the Metropolitan Systems plans, the Metropolitan Development Guide, and compatible with the plans of adjacent communities; and WHEREAS, the Metropolitan Council has approved the amendment at their meeting of December 17, 1987; NOW, THEREFORE BE IT RESOLVED, that the Comprehensive Plan be hereby amended to provide a description of on site sewage treat- ment regulations and to provide policies and program descriptions to reduce infiltration and inflow as shown in "Exhibit A". Passed and adopted by the Chanhassen City Council this 16th day of November, 1987. 7 ATTEQ, C)t:v Don Ashworth, C1ty Clerk/Manager YES NO ABSENT e Hamilton Horn Boyt Johnson None Gevinq - . e e e PROPOSED AMENDMENT TO COMPREHENSIVE SEWER PLAN REGARDING ON-SITE TREATMENT SYSTEMS Page U-19 The proper functioning of on-site treatment systems is a concern of both the Metropolitan Council and the City of Chanhassen. The Sewer Facility Agreement entered into between the City of Chanhassen, the Metropolitan Council and the Metropolitan Waste Control Commission required that the City include in its sewer plan a description of adopted on-site sewage disposal ordinance provisions consistent with applicable requirements setforth in the Metropolitan Council's Comprehensive Sewer Policy Plan, including Policies 42-47 and Procedure 10. The following describes existing regulations and reviews policies relating to existing systems and future subdivisions containing on-site systems. Current Ordinance provisions e In 1983, Chanhassen adopted an On-Site Treatment System Ordinance consistent with Metropolitan Council guidelines (Ordinance 10-A). At that time, the City had ordinances in place which essentially prohibited construction in the unsewered area, except for those parcels that were legally in existence on the date of the adop- tion of those ordinances. However, as a result of a court deci- sion, the City amended its ordinance to permit development on a one unit per 2.5 acre basis. As required by the Sewer Facility Agreement, the City amended its Zoning Ordinance in 1987 to pro- hibit continuation of developments at a 1 unit/2.5 acre density. Rather, it now enforces a 1 unit/lO acre density standard. Because several subdivisions occurred under the 1 unit/2.5 acre ordinance standard, the City initiate~ an ordinance amendment to its on-site treatment controls to strengthen its standards. Ordinance 10-A was amended in 1987 (Ordinance 10-B). The former ordinance adopted the WPC-40 restrictions recommended by the MWCC and MPCA. The ordinance also required licensing of designers, installers, and pumpers; required certain installation data; provided for a process to correct failing systems; and required tank pumping once every three years. The new ordinance . was revised with the help of consultation services from the Soil Conservation Service and the University of Minnesota Agricultural Extension office. Mr. Roger Machmeier who was the primary con- sultant in this process, is from the University of Minnesota and is continuing his consulting services to review soil boring data in conjunction with subdivision applications as well as advising the City in repairing failing septic systems. e The recently adopted ordinance strengthened several requirements. First, it adopts by reference the state regulations, Minnesota Rules Chapter 7080. The Individual Sewage Treatment System Advisory Committee (an MPCA created committee)is proposing several technical changes to Chapter 7080. The City, in order to enforce the most current standards, passed a resolution adopting the proposed rule changes on developed by the committee to act as e e e e e Page 2 guidelines for septic system designs. The ordinance was also changed to permit alternative systems, such as mound and SB-2 systems, and provides regulations for their installation. Ordinance compliance, permit information, and licensing require- ments were also improved to require pumping reports on a monthly basis from pumpers; to require annual licensing procedures for designers, installers, and pumpers; and to submit detailed design plans and plot plans indicating two drainfield sites for each lot. The City has consequently proceeded to improve its record keeping processes as well as beginning an educational program to increase awareness of septic system users of the necessity to properly maintain the system. Upon issuance of each permit, the pamphlet "Get to Know Your Septic Tank" (from the University of Minnesota Agricultural Extension Office) is distributed, as well as information regarding the ordinance requirement to pump the tank once every three years. The ordinance also establishes the ability of the inspector to perform inspections to determine compliance with the provisions of the ordinance. The City, given the amount of systems that will be installed in the rural area, will establish an inspection program to insure compliance with its ordinances. Existing On-Site Systems There are areas located immediately outside the Year 2000 MUSA Line which contain septic systems. Because there have been system failures near these areas, it can be expected that other systems within the area would fail sometime in the future. Where septic system failures occur, the current ordinance provides for proce- dures to repair or replace the system on a timely basis. However, if it is determined that no alternative system can be placed on the property, the parcel should be connected to the City sewer system if it can be serviced by gravity sewer flow and if the property is located immediately outside the Year 2000 MUSA line. A MUSA amendment would be necessary. Two areas of the city exemplify this situation. The area adjacent to the MUSA line along Lake Lucy Road has already experienced septic system failures causing the necessity to amend the MUSA line to include sixteen parcels along West 65th Street and Crestview Drive. The other area is located just north of Lyman Boulevard, west of Lake Riley where the MUSA line jogs to the north excluding about 40 acres. The city is currently evaluating these areas and others to determine whether or not gravity sewer flow can be achieved to these areas. A comprehensive review of the MUSA line should be undertaken to avoid piecemeal applica- tions. Future Subdivisions Concurrent with the ordinance amendment process to the On-Site Treatment System Ordinance, the City also amended its Subdivision " " e e I. e e Page 3 Ordinance (Ordinance No. 33-E) in 1986 to require the submission of soil boring data and identification of two septic system sites for each proposed lot. This data is reviewed by City staff and its consultant to determine that each lot contains two drain- field sites and contains adequate buildable area for the two sep- tic system sites, house pad, appropriate location of the well, and appropriate setbacks as required by City ordinance from wetlands and lakes. The ordinance also specifically prohibits location of septic systems on slopes in excess of twenty-five percent. The City's ordinance and administrative procedures are consistent with and enforce Policies 42-47 and Procedure 10 of the Metropolitan Council Waste Quality Plan. e . e PROPOSED AMENDMENT TO COMPREHENSIVE SEWER PLAN INFILTRATION AND INFLOW Page U-7 The Sewer Facility Agreement entered into between the City of Chanhassen and the Metropolitan Council and the Metropolitan Waste Control Commission required that the City amend its sewer plan to include a policy, ordinance, and administrative program to reduce stormwater inflow in the sewer system consistent with the Metropolitan Waste Control Commission's policies. In 1982, the City conducted a study on the extent of the infiltration/ inflow problem in Chanhassen ("Report on Infiltration/Inflow Analysis", prepared for Schoell & Madson by Planning, Design and Research, 1982). This report, which was reviewed by the MWCC and Metropolitan Council, identified problem areas in the City. Based on the information contained in this report, the City has established several programs to address the infiltration/inflow problem and is developing additional programs to strengthen this effort. e Infiltration/inflow is the amount of extraneous (clear) water flowing into a sanitary sewer. Infiltration is defined as the water entering a wastewater collection system (sanitary sewer system and service connections) from the ground, through such means as defective pipes, pipe joints, connections or manhole walls. Infiltration, however, is distinguished from inflow. Inflow is defined as the water discharged into the sanitary sewer system, including service connections from such sources as roof leaders; cellar, yard, and area drains; foundation drains; cooling water discharges; drains from springs and swampy areas; manhole covers; and cross connections from storm sewer. The 1982 report stated that Chanhassen's sanitary sewer collec- tion system is in "generally good structural condition"; however, there are several sections in the downtown area that contain disintegrated pipes and manholes. The study also identified the importance for an effective maintenance program to find and correct these types of defects. A numerous amount of foundation draintile and sump connections exist in the older neighborhoods north of the downtown area, which was also cited as a contributor to the 1/1 problem. Two lift stations were also identified as experiencing flows in excess of their design capacity. e To address these problems, the City is using a variety of methods. In 1987, the City Council approved the Downtown Redevelopment Project which includes replacement of sanitary sewer lines in the downtown area as well as the establishment of a new storm sewer system. These improvements will eliminate a large part of the 1/1 identified in the 1982 report. The improvements are expected to be completed in 1988. Secondly, the City Council adopted Ordinance No. 5 which prohibits discharging into the sanitary sewer system of any "surface or sub-surface waters". Sump pumps are also required to have an outside discharge. Further, the City will be televising the residential areas north of the downtown area (approximately e - Page 2 e 29,000 ft.) to locate defects in the system. This area was specifically cited in the report for televising. The City will follow with an annual rehabilitation program, and budget for system rehabilitation and televising on a ten year frequency. The City Council has also begun a policy of requiring new sewer construction to be televised prior to its acceptance by the City for maintenance. The maintenance department has been increased to 3 full-time people and one part-time person. As an example, a number of manholes have been sealed this year, which is an example of the on-going necessity to maintain the system. The City has allocated monies in the 1988 and 1989 budgets for acquisition of a telemetry system for lift stations (such as the ones identified in the 1982 report) to increase response time by City personnel to attend the lift station to prevent environmen- tal harm or basement backups. The most difficult aspect of the 1/1 problem is to correct inflow from individual households. The City intends to embark on a program to address the inflow contribution from private proper- ties such as illegal sump pump connections or connections by foundation drains. A process will be implemented to document illegal connections and to provide the property owners other drainage options such as installation of small diameter storm sewers. e In summary, the following lists the type of projects to be under- taken by the City in a five year timeframe. Other problems may occur within that timeframe that would generate additional measures, however, the following represents a solid foundation to attack excessive 1/1. Project Description Implementation Period 1. Annually televise existing sewer lines in older 1/1 suspect areas. Approximately 30,000 feet will be televised initially to identify defects. 1987-1992 2. Annual Rehabilitation - Pending outcome of televising project as well as typical maintenance procedures, defective pipes and manholes will be repaired or replaced. On-going To be included in annual budget. e 3. Televising New Sewer Mains - Prior to acceptance of new sewer mains by the city, the developer shall be required to televise the mains and make any necessary repairs to meet the City's standards for sewer construction. On-going e e Page 3 e Project Description Implement~tion Period 4 . Residential Connections - Illegal sump pump connections and foundation drains to be identified in older residential/excessive 1/1 areas. 1988-1990 for residential area north of the downtown area. To be included in annual budget. a. City staff will develop and present to city officials techniques for eliminating clear water connections and funding options to carry out the disconnection program. b. Implementation of the disconnection program with annual progress report to the MWCC. e 5. Telemetry System - Telemetry equip- ment will be installed on major wastewater pump stations and connected to the Public Works Offices to facilitate more rapid response to equipment during flow emergencies. This would reduce potential health and environmental impacts by waste- water flows and backups. 1988-1989 Fighting infiltration/inflow is a never ending battle. It is not just the responsibility of a local government, but rather it is an effort required by all affected units of government to control 1/1. The MWCC is responsible for maintenance of the Lake Ann Interceptor which is a significant part of the overall system. Cooperative efforts between agenies is important in addressing this issue. To be added to Page GP-8 of the plan regarding goals and policies pertaining to utility systems: GOAL: Preventing and reducing excessive infiltration and inflow shall be a priority in maintenance programs and the design/installation of new sewer construc- tion. Existing and proposed sewerr services shall be maintained or installed so that excessive infiltration and inflow does not occur. e The City shall develop and enforce the necessary ordinances and programs to address the excessive infiltration and inflow problems identified in the "Report on Infiltration/Inflow Analysis", Schoell and Madson, 1982. e . e I I e POLICIES: e e Page 4 The City shall require televising of newly installed sanitary sewer mains prior to acceptance. The City shall carry out an ongoing maintenance program including televising sewer mains, repair and replacement of defective pipes and manholes, and other means to control 1/1 on a daily basis. Clearwater discharges from surface and subsurface drainage, and cooling water to the sanitary sewer system are not permitted. The city intends to develop and implement a program to eliminate such connections.