Chapter 7: Sanitary Sewer Plan. Introduction. Metropolitan Council Coordination

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1 Chapter 7: Sanitary Sewer Plan Introduction The 2030 Sanitary Sewer Plan was prepared for two primary reasons. The first purpose is to provide recommendations and guidance to the City of Lino Lakes by evaluating the sewer system requirements needed from now to the year 2030 and beyond. This is completed by developing a strategy to implement a sanitary sewer system in accordance with the anticipated growth and development patterns of the City, as forecasted in the City of Lino Lakes 2030 Comprehensive Plan, and devising a proposed infrastructure system that can be feasibly and economically constructed to support this growth. The second purpose is to produce documentation that can be used by state and local agencies for future local and regional planning purposes. This Plan focuses on the City s future growth and development patterns and evaluates the capacity and hydraulic capabilities of both the City s existing and future proposed sanitary sewer system. A detailed field review of the lift stations was not completed, nor was any sewer televising reviewed to evaluate the physical condition and operational performance of the existing infrastructure. A detailed maintenance schedule is not provided; rather, it is assumed that the City s on-going maintenance procedures will be followed to determine the scope and schedule of future facility upgrades. Based on the ultimate-development forecasted densities, the City can accommodate about 19,500 residential units, including the Correctional Facility. In addition, new commercial employment at ultimate build-out can total approximately 15,600 employees. Much of this development is projected to occur after Nevertheless, in comparing the City s staging plan with the potential build-out scenarios, it appears that many areas of the City could see significant development before 2030, particularly in Districts 1 and 2. In addition, extensive commercial/ industrial development is anticipated, especially in Districts 3 and 5. Therefore the capacity of existing and proposed sewer facilities has been evaluated based on ultimate development. Using the new forecasts for housing development and employment, ultimate sanitary sewer flows were determined and the facility improvements necessary have been identified and summarized in the report. We conclude that with the additional facilities proposed, the growth that has been forecasted by the City can be accommodated by City s sanitary sewer system. Metropolitan Council Coordination The 2030 Sanitary Sewer Plan is required to be submitted to the Metropolitan Council Environmental Services (MCES) for review and approval. By submitting this document, the City will be formally requesting that MCES adequately provide treatment and interceptor capacity in accordance with the City s projected growth and development. This document replaces the Public Facilities Plan - Sewer Element of the City s 2001 Comprehensive Plan. MCES reviews the plans completed and submitted by Lino Lakes and surrounding communities, and utilizes those documents to assess service capacity and required infrastructure needs throughout the region. The City of Lino Lakes is responsible for providing MCES with a Plan that provides sanitary sewer service capacity requirements. The City is also responsible for providing notification to MCES of accelerated development to allow them to accelerate their infrastructure improvements. 7-1

2 Beginning in April 2003, City staff coordinated extensively with MCES to determine the MCES sanitary sewer capacity allocations and future infrastructure planning as they relate to the City of Lino Lakes. MCES responded by indicating that they are in the process of updating their comprehensive planning for the area served by the Forest Lake Interceptor, with an eye to providing additional future capacity in that Interceptor, which serves the eastern part of Lino Lakes. As a result of these discussions, MCES constructed a new interceptor, known as the Lino Lakes Relief Interceptor, from the Lino Lakes corporate boundary to the Forest Lake Interceptor in In addition, MCES determined that additional capacity was needed for both Lino Lakes and Blaine in the North Suburban Interceptor system. Final design of a new Southeast Anoka County Interceptor, which will provide adequate capacity for projected development in Lino Lakes District 2, is now in process. Background and Scope of Plan Background The City of Lino Lakes has a total area of approximately 21,450 acres. The Chain of Lakes Regional Park includes approximately 3,000 acres of land and several lakes. The I-35W and I-35E corridors occupy about 520 acres. The remainder of the City includes extensive wetland areas and several small lakes. Sanitary wastewater generated in the City is either treated in on-site systems or is collected in city owned sanitary sewers and conveyed to Metropolitan Council interceptors for treatment at the Metropolitan Wastewater treatment Plant in St. Paul. On-site treatment systems are generally located on larger lot developments in the City. Most are in unsewered areas but a few remain in neighborhoods that received service after on-site systems were built. The existing Lino Lakes sanitary sewer system is shown on the Existing Sanitary Sewer System Map, Figure 7-1. For sewer planning purposes, the City has been divided into several Sewer Districts, as shown on the attached Sewer District Map (Figure 7-2). District boundaries are based on the areas that can potentially be served by the various existing and future regional facilities serving the City. The City s Comprehensive Sewer Plan was originally adopted in Portions of the 1990 Plan were updated in 1999 and incorporated into the City s 2001 Comprehensive Plan as Public Facilities Plan - Sewer Element. Planning Scope The scope of this Plan is to develop documentation for sanitary sewer system requirements for the City of Lino Lakes. The scope is limited to providing general guidance and alignment information for implementing future trunk sewer lines and wastewater lift stations, based on the anticipated long-term growth of the City. The final location and detailed design of these trunk sewers and lift stations must be determined and prepared at later dates to conform to the development at each wastewater service area. By following the recommendations of this 2030 Sanitary Sewer Plan, the City will be able to maintain growth without outpacing the available sewer system. Furthermore, the 2030 Sanitary Sewer Plan will provide a more effective and cost-efficient overall system. A major focus of this Plan is estimating the projected wastewater flow from the City and the required capital improvements to the City sewer system over the next several years (i.e., through 2030). At the same time, a long-term (beyond 2030) evaluation is necessary to determine future major facility requirements. Understanding these long-range requirements will allow the City to acquire 7-2

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5 sites for their construction and to install initial improvements with adequate size and capacity to convey the future sewer system needs. This Plan should be revisited and updated whenever the development types, densities, growth rate, and/or water use patterns deviate significantly from those estimated herein. The geographic area covered by this Plan includes the entire City with the exception of the Regional Park and freeway corridors. It is understood that complete development of all areas of the City is not expected to occur within the planning period. The proposed facilities have been sized to accommodate projected full build-out. Vision, Goals and Policies The new development forecasts for the City describe the current growth and expected development patterns. The forecasts were developed through a collaborative effort guided by the Citizen Comprehensive Plan Advisory Panel to review past planning documentation and to evaluate the changing demographic conditions and influencing factors. Population projections, land-use, and future growth patterns have been estimated. MCES plans for interceptor sewers and treatment capacities located in the Metropolitan Wastewater Treatment Plant service area inform the Plan, which follows both the Metropolitan Council's Systems Plan - City of Lino Lakes and the Metropolitan Council's Local Planning Handbook. The City s 2030 Sewer Plan evaluates the existing sanitary sewer system to determine the adequacy of the system based on current conditions. This involves updating the existing sewer map and determining the available capacity of existing trunk sewers. Utilizing this information, the Plan provides the guidance and information on future trunk sewers and lift stations necessary to accommodate the City's forecasted growth. This involved reviewing and updating the City's proposed land-use and staged development map, estimating the number of housing units and commercial/industrial properties in the future development sites, and providing solutions for the connection of new lateral sewers to the existing trunk sewer system. The general alignment of new trunk sewers and lift station locations is provided. Figure 7-3 shows the sanitary system compared to future land use and Table 7-1 summarizes existing and ultimate sewered population units. The Citizen Visioning Committee and the Citizen Comprehensive Plan Advisory Panel created goals and strategies to achieve the community vision. The planning done for the 2030 Sanitary Sewer Plan supports this Vision. The cost-effective expansion of the sanitary sewer system indirectly supports achieving many of the City's goals, and, obviously, directly achieves the sanitary sewer goal (Goal 5) identified in the Lino Lakes 2030 Comprehensive Plan Goals and Strategies document. Natural Resources and Amenities Goal 1: Identify, protect and preserve the desirable natural areas and ecological and aquatic resources of the community. Goal 2: Initiate and continue vigorous collaborations and programs to address, restore, and preserve the water quality of the regions lakes, wetlands and other aquatic assets. Sanitary Sewer Support: Careful expansion of sanitary sewer service in support of desired development assures that natural aquatic assets are protected from waterborne household and commercial waste products. 7-5

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7 Table 7-1. Summary Of Development Projections Through 2030 Dist. Sub-Dist. Residential Units Existing Sewered ISTS Hookups Projected New Units Total Sewered Units Commercial / Industrial Projected New Employment 1 1A B , C D E F G H Sub-Total 2, , A B C D E F , G H I ,085 1, J Sub-Total 1, ,669 3, A B 9 1,243 1, C D E F G Sub-Total ,847 2,366 1, A B C D E Sub-Total A ,408 5B C Sub-Total ,408 TOTAL 4, ,600 9,975 4,080 Plus correctional facility (Sub-District 2E) assumed equivalent to 500 residential units TOTAL 4,950 10,475 4,

8 Land Use Policies and Practices Goal 1: Ensure that well-planned, quality residential, commercial, industrial and institutional development to accommodate the City's projected growth needs occurs in a manner that also conserves and enhances the city's natural resources and amenities. Sanitary Sewer Support: Sanitary sewer service expansion, like water service and local street improvements, should be planned to coincide with the timing of desired development, and public sanitary sewer service should be planned in areas identified as having failed on-site sanitary disposal systems, thus protecting both ground and surface water quality. Other Ecological Challenges and Threats Goal 1: Identify and work cooperatively with the state and other local government entities to develop approaches for addressing potential ecological challenges and threats that could adversely affect Lino Lakes. Sanitary Sewer Support: Public sanitary sewer improvements should be planned in areas identified as having failed on-site sanitary disposal systems, protecting both ground and surface water quality from contamination. Community Facilities Goal 5: Maintain the City's residents and businesses with an affordable and safe sanitary sewer system. Policies: 1. Provide a low-maintenance, cost-effective sewer system that meets the long-term needs of the City's residents and businesses. 2. Provide sanitary services to undeveloped areas in a planned manner. 3. Provide for the capacity and extension of sanitary sewer to developed areas of the city currently served by on-site systems. 4. Establish an on-site septic system inspection program to identify potential failing systems. 5. Where possible, direct public sanitary sewer improvements to areas identified as having failed on-site systems. The 2030 Sanitary Sewer Plan directly addresses all of these Policies. Tasks As a first task in the planning process, current growth and development patterns of the City were reviewed in light of past planning documentation and changing demographic conditions. Population projections, land-use, and future growth patterns were estimated. MCES was contacted regarding its future plans for interceptor sewers and treatment capacities located in the Metropolitan Wastewater Treatment Plant service area. Next, the existing sanitary sewer system was evaluated to determine the adequacy or deficiency of the system, based on current conditions. This involved updating the existing sewer map and determining the available capacity of existing trunk sewers. 7-8

9 The third task involved providing guidance and information on future trunk sewers and lift stations that will be necessary to accommodate the City s anticipated growth and development. This included reviewing and updating the City s proposed land-use and staged development map, estimating the number of housing units and commercial/industrial properties in the future development sites, and providing solutions for the connection of new lateral sewers to the existing trunk sewer system. The general alignment of new trunk sewers and lift station locations was determined. Each lift station s general service area was identified. The final task was the preparation of a Plan document summarizing the findings of this investigation and formulating recommendations to the City Council. Lino Lakes Demographic Profile and Forecasts Background The community of Lino Lakes anticipates significant growth in upcoming years. Planning for growth poses significant opportunities and challenges for the community. The City s land use plan is an important tool to ensure that the City is adequately prepared to respond to these opportunities and challenges. The land use plan plays a key role in managing growth within the City. The land use plan builds on the plan vision, goals, and strategies to establish a policy framework in which future development will occur. The future land use map is also used to estimate the community s capacity to accommodate projected household and employment growth. Sewer, water, and transportation infrastructure plans are based on the forecasts and development information presented in the land use plan. Figure 7-3 shows the existing sanitary sewer system and proposed future trunk sewers superimposed over the proposed Future Land Use Plan. Chapter 3: Land Use includes a more detailed discussion of land use and development trends. Past Growth Trends The population of Lino Lakes has grown from 8,807 in 1990 to 16,791 in 2000, an annual increase of 6.7 percent. The Metropolitan Council estimates that the 2005 population of Lino Lakes was 19,698 while the number of households was 5,729. These figures represent annual increases (since 1990) of 5.5 percent in population and 5.4 percent in the number of households. Forecasts Detailed forecasts of land use, population, and employment are included in the 2030 Comprehensive Plan. These forecasts, broken out by sewer planning districts, are briefly summarized below. Existing development by district, as of 2008, is also summarized. District boundaries are shown on Figure 7-2. Forecasts by Sewer Districts Sewer District 1 Sewer District 1 is located in the southwest corner of the City. A significant portion of District 1 is currently developed. As of 2008, District 1 contains approximately 2,260 sewered single family residential units and 350 un-sewered units. There are about 740 developable acres in District 1 currently designated as low density sewered residential, 82 acres designated as medium density residential, 21 acres designated as mixed use-residential, 12 acres designated mixed usecommercial, and 7 acres designated commercial. 7-9

10 The residential areas, including undeveloped lots in the existing subdivisions, are projected to accommodate about 770 new residential units by In addition, approximately 220 existing homes with on-site systems are projected to connect to the sewer system by The total number of sewered residences in District 1 would then be about 3,250 units in In addition, the commercial and mixed use areas will support approximately 140 new employees by Sewer District 2 Sewer District 2 is located in the northwest corner of the City. This area consists of a mixture of urban and rural land uses. District 2 currently contains about 1,710 sewered residential units, 1,085 un-sewered units, and 185 vacant lots in existing developments. This District also contains about 1,220 developable acres designated as low density residential. There are also about 231 developable acres designated as medium density residential, 114 developable acres designated as high density residential, and 60 acres designated as mixed use residential. In total, these areas are projected to support approximately 1,670 new residential units by In addition, District 2 includes the Lino Lakes Correctional Facility. The Correctional Facility houses approximately 1,200 residents, equivalent to about 500 single family residential units. In total, assuming approximately 570 existing un-sewered residential areas receive service, District 2 could contain the equivalent of about 4,450 sewered residential units in District 2 also includes extensive existing commercial and industrial area, as well as approximately 108 developable acres designated commercial, 23 developable acres designated as industrial, and 16 acres designated mixed use - commercial. Projected new employment in the commercial, industrial and mixed use areas totals about 760 employees by Sewer District 3 Sewer District 3 is located on the east side of the City, generally east of Centerville. District 3 also includes sub-district 3F, two small developed areas totaling about 40 homes in the Lamotte Drive area and at the west end of Mound Trail on the north side of Centerville Lake. Sub-district 3F is served by an interconnection to the Centerville sanitary sewer system and by MCES lift station L-4. Existing sewered areas of District 3 contain about 480 existing single family residences, and a few commercial properties. The District also includes about 100 unsewered residences. District 3 contains approximately 247 acres of developable land designated as low density residential; 207 developable acres designated medium density residential; 25 developable acres high density residential; and 302 developable acres designated as mixed use residential. In total, these areas are projected to support approximately 1,850 new residential units by Assuming 40 existing unsewered residences receive service, total sewered residential development in District 3 is projected to be approximately 2,370 units by District 3 also includes approximately 104 developable acres designated commercial, 122 acres designated industrial, and 67 acres designated mixed use-commercial. Total new employment in these areas is projected to be approximately 1,720 employees by Sewer District 4 Sewer District 4 is located in southeastern Lino Lakes, bordering on North Oaks and White Bear Township. There is no existing sewered development in District 4. There are about 140 existing non-sewered residences. District 4 contains approximately 597 developable acres designated low density residential, 48 acres medium density, 9 acres high density, and 20 acres mixed use residential. Most areas of District 4 will probably not be developed by Projected development by 2030 includes about 320 new residential units. In addition, 90 existing units are projected to receive service, resulting in about 410 sewered units in District 4 by In addition, District 4 contains approximately 11 acres designated as mixed use commercial, which could support about 50 employees by

11 Sewer District 5 District 5, located in the northeast corner of the City, is largely rural at present. There is no existing sewered development in this area. There are about 40 existing un-sewered homes and a church located near Peltier Lake. District 5 includes about 150 developable acres designated as low density residential, 299 acres medium density residential, and 41 acres mixed use residential. It is expected that little or no residential development will occur in District 5 before A large portion of District 5 is designated for future industrial (588 acres), commercial (279 acres), and mixed use commercial (9 acres) land uses. Most of these areas will not develop before Total new employment in District 5 is estimated at about 1,410 employees by Sewer District Forecast Summary Based on the 2030 forecasts described in the preceding paragraphs, the City is expected to contain approximately 10,500 equivalent sewered residential units (including the Correctional Facility) by In addition, new commercial/industrial employment by 2030 could total approximately 4,080 employees. Development projections for 2030 are summarized in Table 7-1. In comparing the City s staging plan with the Full-Build-Out Future Land Use Map, it is apparent that large areas of developable land will remain after In addition, in-fill development and redevelopment will continue to occur. Full build-out of proposed residential, commercial, and industrial areas will result in ultimate sewer flows substantially greater than projected 2030 flows. It is therefore prudent to evaluate the capacity of existing and proposed facilities based on ultimate development. Wastewater Flow Projections and Design Flows Water use is associated with population more than any other parameter, and in particular, the per capita consumption is the industry standard for computing water use and, therefore, wastewater flow generated. Both the Minnesota Pollution Control Agency (MPCA) and the Metropolitan Council Environmental Services (MCES) have compiled and documented extensive data that relates wastewater flow generation to population and land-use. This information has been used as our basis for estimating the wastewater design flows and peaking design conditions to determine the size and capacity of the existing and future sewer systems. MCES has established 274 gallons per day (gpd) to be the average daily wastewater production from a typical residential equivalent unit (1 REU = 274 gpd). The following parameters were used for the wastewater flow projections throughout this Plan: Residential Equivalent Unit (REU) = 274 gpd or 100,000 gallons per year Commercial/Industrial Development: 40 gpd per employee or 1,000 gpd per net acre Correctional Facility: 110 gpd per resident; 2.5 residents equals one Residential Unit (REU) Design flows for piping and pumping facilities are based on peak wastewater flow conditions. Peaking factors vary with the total contributing population. The greater the population in the service area the less variable the wastewater flow condition is with time. Standard peaking factors developed by the MCES, as shown in Table 7-2, were utilized to estimate peak flows. Projected average daily flows and peak flows for years 2015, 2020, 2025, 2030, and at ultimate development are summarized in Tables 7-3 through

12 Table 7-2. MCES Standard Peaking Factors Peak Flow Factor Average Daily Flow Limits (MGD) to to to to to to to to to to to to to to to to to to to to to to to Over

13 Table 7-3. Summary of Projected Flows All Flows in Millions of Gallons Per Day (MGD) Dist. Sub-Dist. Average Daily Flow Residential Non- Residential Total Peaking Factor Peak Flow 1 1A B C D E F G H Subtotal A B C D E F G H I J Subtotal A B C D E F G Subtotal A B C D E Subtotal A B C Subtotal Total

14 Table 7-4. Summary of Projected Flows All Flows in Millions of Gallons Per Day (MGD) Dist. Sub-Dist. Average Daily Flow Peaking Factor Peak Flow Non- Residential Total Residential 1 1A B C D E F G H Subtotal A B C D E F G H I J Subtotal A B C D E F G Subtotal A B C D E Subtotal A B C Subtotal Total

15 Table 7-5. Summary of Projected Flows All Flows in Millions of Gallons Per Day (MGD) Dist. Sub-Dist. Average Daily Flow Peaking Factor Peak Flow Non- Residential Total Residential 1 1A B C D E F G H Subtotal A B C D E F G H I J Subtotal A B C D E F G Subtotal A B C D E Subtotal A B C Subtotal Total

16 Table 7-6. Summary of Projected Flows All Flows in Millions of Gallons Per Day (MGD) Dist. Sub-Dist. Average Daily Flow Peaking Factor Residential Non- Residential Total Peak Flow 1 1A B C D E F G H Subtotal A B C D E F G H I J Subtotal A B C D E F G Subtotal A B C D E Subtotal A B C Subtotal Total

17 Table 7-7. Summary of Projected Flows Ultimate Development All Flows in Millions of Gallons Per Day (MGD) Dist. Sub-Dist. Average Daily Flow Peaking Factor Peak Flow Non- Residential Total Residential 1 1A B C D E F G H Subtotal A B C D E F G H I J Subtotal A B C D E F G Subtotal A B C D E Subtotal A B C Subtotal Total

18 Metropolitan Council Environmental Services (MCES) Metropolitan Urban Service Area (MUSA) Boundary The MUSA boundary is the boundary in the seven-county Twin City Area within which the Metropolitan Council commits to provide sanitary sewage treatment and conveyance via regional interceptors. The Metropolitan Council required each community in the MUSA to provide a Plan Update in These Plans developed MUSA staging lines in five-year increments up to the year In Lino Lakes, the Stage 1 Utility Staging Area is the MUSA boundary. Collaboration with Metropolitan Council Environmental Services (MCES) Complete sewer collection and treatment service for the City of Lino Lakes is provided through a collaborative effort between the City and MCES. The City is required to provide local sewer collection services in accordance with the City s Comprehensive Plan. Wastewater collected within the City limits is conveyed into MCES interceptors. The collected sewage and the sewage from other communities are then conveyed to the MCES Metropolitan Wastewater Treatment Plant (WWTP), located in the City of Saint Paul. In recent years, there has been substantial growth in Lino Lakes and adjacent communities. MCES is aware of this growth and is reviewing the Plans submitted by each community in this region to evaluate their future wastewater collection, treatment, and infrastructure capabilities. MCES wastewater treatment facilities and interceptor systems are designed based on projected regional land-use and growth plans. Therefore, any significant changes in future land-use and development of the City will have an impact on MCES facilities. MCES Interceptors and Lift Stations Serving Lino lakes The City of Lino Lakes sewer system currently discharges to the MCES Interceptor system at four locations. Sewer District 2 is served by MCES Interceptor 83-61, located in North Road on the Lino Lakes/Circle Pines boundary. Service to District 1 is provided by MCES Lift Station L69, located on Ware Road. Sub-District 3F discharges to MCES Lift Station L4, located at the Lino Lakes/Centerville Corporate boundary. The MCES Centerville Interceptor (Interceptor 76-51), located in Cedar Street, receives the pumped discharge from Lift Station L4, as well as flow from Sewer District 3. Lino Lake s flows will be discharged to the regional system at two additional locations in the future. Sewer District 4 will be served by a White Bear Township trunk sewer, ultimately discharging to the Forest Lake interceptor. District 5 will be served by the newly constructed Lino Lakes Relief Interceptor. The locations of these facilities are shown on Figure 7-1. The following paragraphs provide a brief description of each of the existing MCES and White Bear Township facilities. MCES Interceptor The existing interceptor is a gravity sewer which provides an outlet for Lino Lakes Lift Stations 2 and 4. MCES Meter Station M211 is located at the discharge end of the forcemain serving these two lift stations. A peak flow capacity of 3.6 Million Gallons per Day (MGD) has been allocated to Lino Lakes at this connection. Interceptor flows west and discharges into the North Suburban Interceptor (4-NS-523). As a result of recent development projections by Lino Lakes, Blaine, and other cities, MCES has committed to provide additional capacity at this location. The proposed Southeast Anoka County Interceptor will provide an allocated capacity of 7.6 MGD for Lino Lakes. 7-18

19 MCES Lift Station L-69 This lift station, located on Ware Road, was constructed in to replace an earlier MCES facility, Lift Station L-53. Lift Station L-69 discharges west through a long forcemain to the North Suburban Interceptor (4-NS-523) in the City of Shoreview. The current design capacity of Lift Station L-69 is 2,760 gallons per minute (gpm) or 3.97 MGD. It can be upgraded to 2920 GPM (4.20 MGD) by changing pump impellers. MCES Meter Station M219 is located at the lift station. MCES Lift Station L-4 The service area of this lift station is limited to a small, fully-developed area of Lino Lakes (District 3F), as well as the City of Centerville. This lift station and forcemain were upgraded by MCES in 2000 to provide for the long-term needs of this service area. MCES Meter Station M210 is located at the lift station. The forcemain discharges into MCES Interceptor at the intersection of 21st Avenue and Cedar Street. MCES Interceptor (Centerville Interceptor) This interceptor is a 24-inch gravity sewer constructed in It flows east into the City of Hugo and connects to the Forest Lake Interceptor. Interceptor receives flow by forcemain from MCES Lift Station L-4, and also from forcemains serving Lino Lakes Lift Stations 7 and 8. MCES Meter Station M220 is located on the Lino Lakes/Hugo boundary on Cedar Street. The interceptor at the Lino Lakes boundary has a gravity capacity of 5.00 MGD, of which approximately 3.65 MGD is available to Lino Lakes. MCES Interceptor (Metropolitan Service to Sewer District 4) Lino Lakes Sewer District 4 is not currently served by an MCES facility. Future sewer service to this area is expected to be provided by way of the White Bear Township sewer system, ultimately discharging to MCES Interceptor Recent projects have extended service to the Lino Lakes boundary at three locations: an 18-inch gravity sewer on the west side of Centerville Road, the North Oaks Company s Rapp Farm lift station at the west end of Wilkinson Lake, and a White Bear Township pressure sewer system east of Otter Lake. The capacity potentially available for Lino Lakes in the White Bear Township system is approximately 2.3 MGD. MCES Interceptor (Service to District 5) MCES recently constructed the Lino Lakes Relief Interceptor, which extends west from the Forest Lake Interceptor (MCES Interceptor 70-29) along Washington County Highway 8 to the Lino Lakes boundary. This sewer will serve District 5. Available capacity for Lino Lakes at this location is 5.6 MGD. Future Improvements to MCES Interceptors City staff and consultants have met with MCES staff numerous times in recent years to discuss existing and future MCES service to Lino Lakes. The MCES is in the process of updating their planning for the Northeast Region, which includes Lino Lakes, Centerville, North Oaks, Forest Lake, Hugo, Forest Lake Township, White Bear Lake, and White Bear Township. They anticipate the need to provide additional capacity in the Forest Lake Interceptor and downstream facilities to serve the future needs of those communities. The MCES also anticipates the need to upgrade portions of the North Suburban Interceptor to serve future development in Lino Lakes and Blaine. The proposed Southeast Anoka County Interceptor is a key part of the North Suburban Interceptor improvement program. This 2030 Sanitary Sewer Plan, as well as the Comprehensive Plans of neighboring communities, will be used by MCES to assess the scope and timing of future interceptor improvements. 7-19

20 Existing Sanitary Sewer System Sanitary Sewer Map Figure 7-1 presents the general alignment and layout of the existing sanitary sewer system. The MCES interceptors, lift stations, forcemains, and meter stations serving the City of Lino Lakes are labeled to distinguish them from the City sanitary sewer system. Existing Sanitary Sewer Collection System Most of the City sanitary sewer system consists of PVC gravity sewer lines ranging from 8 inches in diameter to 24 inches in diameter. Lateral sewers serving residential areas are typically 8 inches in diameter, and discharge into 10 inch or larger trunk sewers. The City also currently owns and operates 13 sanitary sewer lift stations which are an integral part of the collection system. The locations are shown on the sanitary sewer system map. Lift stations 1 through 12 were constructed by the City. Lift Station L53 was originally an MCES facility, but was conveyed to the City by MCES in 1998 following construction of new MCES lift station L69. Design information on existing lift stations is summarized in Table 7-8. A brief description of the existing lift stations and their service areas follows. Table 7-8: Existing Lift Stations Lift Station Pumps: Lift Station Address No. No./Capacity/HP Capacity Black Duck Drive 2 pumps/775 gpm/23 HP +1 pump/800 gpm/25 HP 880 gpm Lake Drive 2 pumps/140 gpm/5 HP 140 gpm Ware Road 2 pumps/210 gpm/3 HP 210 gpm Gladstone Drive 3 pumps/1,000 gpm/25 HP 2,000 gpm Snow Goose Trail 2 pumps/300 gpm/10 HP 300 gpm Stagecoach Trail 2 pumps/200 gpm/3 HP 200 gpm Cedar Street 2 pumps/150 gpm/7.5 HP 150 gpm st Avenue 2 pumps/250 gpm/15 HP 250 gpm Ware Road 2 pumps/230 gpm/5 HP 230 gpm Century Trail 2 pumps/300 gpm/10 HP 300 gpm Kelly Street 2 pumps/150 gpm/7.5 HP 150 gpm Village Drive 2 pumps/250 gpm/5 HP 250 gpm L Laurene Avenue 2 pumps/240 gpm/5.5 HP 240 gpm Lift Station No. 1 Located on Black Duck Drive near Birch Street, this lift station currently serves Sewer Sub- Districts 1D and 1F. Future sewer service to Sub-District 1G will also ultimately drain to Lift Station 1. Lift Station No. 1 was reconstructed in 2003 and has three submersible pumps. The station s capacity is 880 gpm with two pumps operating. Lift Station No. 1 discharges via forcemain to the gravity sewer in Country Lakes Drive. Lift Station No. 2 This lift station, located at Lake Drive and 2nd Avenue, serves a small area adjacent to Rice Lake. It discharges to the MCES gravity sewer at Meter Station

21 Lift Station No. 3 This lift station was constructed at its current location in 1998 as part of a general reconfiguration of sewer lines in District 1 associated with the construction of new MCES Lift Station L69. Old Lift Station No. 3, which was located at 6290 Ware Road, was converted into a manhole discharging into the MCES lift station. The new lift station provides service to future residential development near the south end of Ware Road. Lift Station No. 3 discharges to gravity sewer in Linda Avenue, and thence to Lift Station L53. Lift Station No. 4 This lift station, constructed in 1989, receives flow from the 24-inch West Central Trunk Sanitary Sewer. All existing sewered areas of Sewer District 2, except for the Lift Station 2 service area, are tributary to Lift Station No. 4. The existing lift station has three pumps housed in an 8.5-foot diameter vault, and discharges through a 14-inch forcemain to MCES Meter M211. Lift Station No. 5 This lift station serves Sub-District 1F. It discharges to existing gravity sewer near Birch Street and White Oak Road, and thence, by gravity to Lift Station No. 1. Lift Station No. 6 Located near Marshan Lake, this lift station serves a small area east of Lake Drive. It discharges into a gravity sewer in 4th Avenue which is part of the Lift Station 4 service area. Lift Station No. 7 This station serves the part of District 3 east of 35E. It discharges to the MCES gravity sewer upstream of Meter M220. Lift Station No. 8 This lift station was constructed in 1999, in conjunction with sewer construction in 21st Avenue. It serves the portion of District 3 west of 35E and north of Cedar Street. It discharges to the MCES gravity sewer at 21st Avenue and Cedar Street. Lift Station No. 9 Located on Ware Road north of Birch Street, this station was constructed in 2002, to serve new development southeast of Rice Lake. It discharges into the sewer system tributary to MCES Lift Station L69. Lift Station No. 10 This lift station, located near the intersection of Century Trail and Pinto Lane, was constructed in 2003 as part of the Century Farms North development. It serves existing development in Century Farms North, and will receive flow from future development in Sub-District 2I. Lift Station No. 11 This lift station was constructed in 2006 as part of the Pine Glen Subdivision. It serves a small area of Sub-District 2B. Lift Station No. 12 This lift station, located southeast of the 35W/Lake Drive interchange, was constructed in It will serve the Legacy of Woods Edge mixed use development, located north and east of City Hall. This area is part of Sub-District 2F. 7-21

22 Lift Station L53 This lift station was originally owned by MCES, but was conveyed to the City following the construction of new MCES Lift Station L69. It discharges via forcemain to Lift Station L69. Lift Station L53 services the southwest corner of the City (Sub-District 1A) and also receives flow from Lift Station No. 3. Existing Sanitary Sewer System Capacity Analysis Trunk sanitary sewers and lift stations were analyzed to determine the existing service capacity and the total available capacity for future development opportunities. Existing wastewater flows were estimated by a combination of pumping records, MCES meter records, and counts of existing residential units. The total capacity of each trunk facility was calculated to determine the available capacity for future growth and development. Tables 7-9, 7-10, and 7-11 summarize projected flows (at ultimate development) and existing capacity at key points in the sewer system. Flows are given in Millions of Gallons per Day (MGD). Where estimated future peak flows exceed capacity, reconstruction or upgrading of the system may be required. For those locations likely to experience flows in excess of capacity within the planning period, future upgrades are addressed in the Capital Improvement Plan. A discussion of future needs and capacity restrictions in the various Sewer Districts is presented in the following paragraphs. Table 7-9. Capacity Analysis - Existing Sewer System - District 1 FUTURE FLOW FACILITY NAME/ LOCATION SERVICE AREA (Sub-Districts) Avg. (MGD) Peak Factor Peak (MGD) EXISTING CAPACITY (MGD) Lift Station #5 (Pumps to LS 1) 1F Lift Station #1 1D, 1F, & 1G REMARKS May Require Upgrade, See Note 2 May Require Upgrade, See Note 2 12" Trunk Sewer, Country Lakes Drive 1D, 1F, 1G, & about 70 homes in 1B May Require Upgrade, See Note 2 Lift Station #9 1H Adequate Capacity 21" Trunk Sewer at Lift Sta. L69 1B, 1D, 1F, 1G, & 1H Adequate Capacity Lift Station #3 1C May Require Upgrade, See Note 2 Lift Station #L53 1A & 1C Requires Upgrade Future MCES Lift Station L69 All of District NOTES: 1. Future Flow estimates are based on ultimate development of the service areas. 2. Theoretical Peak Flow Exceeds Capacity. The facility may still function due to storage in pipes. Monitor flows as development progresses. 7-22

23 Table Capacity Analysis - Existing Sewer System - District 2 FACILITY NAME/ LOCATION SERVICE AREA (Sub-Districts) Avg. (MGD) FUTURE FLOW Peak Factor Peak (MGD) EXISTING CAPACITY (MGD) Lift Station #2 2H REMARKS Requires Future Upgrade Lift Station #6 2G Adequate Capacity Lift Station #10 Option 1 2I & 2J Option 2 2I Requires Future Upgrade Requires Future Upgrade 15" Sewer, Lilac Lane/4th Avenue Option 1 2E, 2I & 2J Option 2 Half of 2E Does Not Have Adequate Capacity Adequate Capacity; See Note 3 21" Sewer, Main Street/Lake Drive/Apollo Drive 2A, 2B, 2C, & 2D Adequate Capacity 24" Trunk Sewer, 4th & Apollo Option 1 Option 2 2A, 2B, 2C, 2D, 2E, 2I, & 2J A, 2B, 2C, 2D, & half of 2E Does Not Have Adequate Capacity Adequate Capacity; See Note 3 24" Trunk Sewer at L. S. #4 Option 1 Option 2 2A, 2B, 2C, 2D, 2E, 2F, 2G, 2I, & 2J A, 2B, 2C, 2D, half of 2E, most of 2F, & 2G Does Not Have Adequate Capacity Adequate Capacity, See Notes 3 & 4 Lift Station #4 Option 1 Option 2 2A, 2B, 2C, 2D, 2E, 2F, 2G, 2I, & 2J A, 2B, 2C, 2D, half of 2E, most of 2F, & 2G Does Not Have Adequate Capacity Upgrade Lift Station & Forcemain MCES SE Anoka County Interceptor All of District New Facility by MCES NOTES: 1. Future Flow estimates are based on ultimate development of the service areas. 2. Option 1 assumes all areas will be served by existing trunk sewers. 3. Option 2 assumes construction of a West Side Relief Sewer serving sub-districts 2I, 2J, half of 2E, and about 800 homes in 2F. 4. Theoretical Peak Flow Exceeds Capacity, but Pipe will Function with Surcharge and Storage in Pipe. 7-23

24 Table Capacity Analysis - Existing Sewer System - District 3 FACILITY NAME/ LOCATION SERVICE AREA (Sub-Districts) Avg. (MGD) FUTURE FLOW Peak Factor Peak (MGD) EXISTING CAPACITY (MGD) Lift Station #7 3A & 3E REMARKS Requires Future Upgrade 15" Trunk Sewer, Clearwater Cr Drive 21" Trunk Sewer, Otter Lake Road 3A South of Cedar Street & 3E Adequate Capacity 3A North of Cedar Street Adequate Capacity 21" Trunk Sewer, 21st Avenue 3B Adequate Capacity Lift Station #8 3B Requires Future Upgrade MCES Interceptor All of District 3 plus - City of Centerville Adequate Capacity See Note 2 NOTES: 1. Future Flow estimates are based on ultimate development of the service areas. 2. Future average daily flow includes MGD from Centerville. Sewer District 1 MCES Lift Station L69, which serves this District, was constructed with substantial reserve capacity and appears to be adequate for the needs of its service area through the planning period. The current capacity of Lift Station L69 is 3.97 MGD, greater than the projected ultimate flow of 3.84 MGD. The existing trunk sewer system and existing City-owned lift stations were also analyzed, and the results are summarized in Table 7-9. The future service needs shown in Table 7-9 are based on ultimate development of the service areas, that is, development of all currently undeveloped land at urban densities. It is also assumed that all existing homes served by on-site systems will either be redeveloped or connected to the sewer system in the future. Ultimate development of all areas of Sewer District 1 is not expected to occur before Sewer District 2 All currently sewered areas of District 2 are served by MCES Interceptor 83-61, a 24-inch gravity sewer located in North Road. The MCES has allocated a capacity of 3.6 Million Gallons per Day (MGD) to Lino Lakes in the existing interceptor. However, the MCES has initiated a program to construct a new interceptor, known as the Southeast Anoka County Interceptor, which will replace existing interceptor The new interceptor will provide at least 7.6 MGD of capacity for Lino Lakes, which will be adequate for full development of District 2. Currently, all existing sewers in District 2, except for a small area near Rice Lake, discharge to the City s West Central Trunk Sanitary Sewer, thence to Lift Station No. 4, and thence by forcemain to MCES Interceptor The existing trunk sewer, lift station and forcemain do not have sufficient capacity for full build-out of District

25 Table 7-10 summarizes future needs and available capacity of existing facilities serving District 2. The needs computed are based on ultimate development of the service area at urban densities, and the eventual conversion of existing homes served by on-site systems to City sewer service. Ultimate development of all areas of District 2 may not occur for many years. However, projected development as summarized in the Demographic Profile and Forecasts section will probably result in flows in excess of available capacity in the City s trunk sewer before Prior to that time, a relief sewer should be constructed to serve the northwesterly and westerly portions of District 2. This relief sewer is discussed further in the Future Sanitary Sewer System section. Table 7-10 includes projected flows in the existing system with a relief sewer in place (Option 2). Sewer District 3 This area is served by MCES Interceptor 76-51, a 24-inch gravity sewer in Cedar Street. This gravity sewer was constructed in 2000 to serve part of Lino Lakes and the City of Centerville. Its capacity is 5.00 MGD, of which approximately 3.65 MGD is allocated to Lino Lakes. This is adequate for ultimate development of District 3. Projected flows in existing trunk sewers and lift stations in District 3 are summarized in Table Sewer District 4 There are no existing sanitary sewers in this part of Lino Lakes. Recently, sanitary sewer facilities have been constructed to the Lino Lakes boundary at three locations. The North Oaks Company extended the 18-inch gravity sewer to the City boundary on the west side of Centerville Road. The North Oaks Company also constructed the Rapp Farm lift station, located in Lino Lakes west of Wilkinson Lake, with sufficient capacity for Lino Lakes Sub-District 4D. White Bear Township constructed a pressure sewer system east of Otter Lake which is sized to serve 90 homes in Lino Lakes Sub-District 4E. The capacity available to Lino Lakes in the White Bear Township sewer is approximately 2.33 MGD, which exceeds the projected Ultimate flow of MGD from District 4. A Joint Powers Agreement between Lino Lakes and White Bear Township must be completed to ensure that this capacity remains available for Lino Lakes use. Sewer District 5 This area was originally included in the service area of MCES Interceptor This interceptor, constructed in 2000, was sized based on land-use planning available at the time, which assumed much of northeastern Lino Lakes would remain rural. Lino Lakes current Land-Use Plan assumes ultimate urban development of most of District 5. Existing Interceptor has adequate capacity for District 3 and Centerville, but not sufficient capacity for all of District 5. Consequently, the MCES in 2006 constructed an additional interceptor, known as the Lino Lakes Relief Interceptor. This interceptor extends west from the Forest Lake Interceptor to the Lino Lakes/Hugo boundary at Main Street, and has a capacity of 5.6 MGD. This capacity is adequate for ultimate development of District 5. Alternative Wastewater Treatment There are currently no community treatment systems, wastewater treatment plants or rural centers plants within Lino Lakes. The City currently contains extensive areas of Low-Density Residential and Rural Land-Use areas not served by the public sewer system. Residences and businesses in these areas are served by individual on-site systems. Lino Lakes currently has 1,910 Individual Sewage Treatment Systems (ISTS) with 26 of those systems in nonconformance or having known problems. The City maintains a database that tracks, year of system construction, ISTS inspection dates, compliance with 7080 rules, and date and volumes of pumping. 7-25

26 Community treatment systems will only be allowed if all of the following conditions are met: - The site must be in a permanent rural area outside the ultimate service area. - The system must meet MPCA requirements. - The system must remain in private ownership. - The private ownership must have a maintenance and management agreement for the system. The agreement must state that the City can repair any public health hazards created by the system and pass those costs along in the form of assessments to the benefited property. The City s policy is to permit unsewered residential properties to remain as long-term land uses, and to extend sanitary sewers into unsewered subdivisions only at the request of the property owners. New installations of on-site systems will generally be restricted to rural land uses with a minimum lot size of 10 acres. Figure 7-4 shows areas served by on-site systems as of January This 2030 Sanitary Sewer Plan assumes that most of these unsewered areas will be converted to sewered development at ultimate development, but some areas will probably not receive sewer service until sometime after Figure 7-4 also shows the known nonconforming systems and systems with known problems. The City s Individual Sewage Treatment Systems ordinance requires biennial inspections of onsite systems. (Triennial inspections are permitted for certain systems which are up to code and have been shown to have less than 50 percent of allowable sludge and scum accumulation.) The City will also consider establishment of a point of sale inspection requirement. The ordinance establishes notification and reporting procedures and requirements for repairs and re-inspection. Failed systems must connect to City sewer if available, as stated in Section 402 of the City Code, or must be repaired. During the period from 2000 to 2008, 241 septic system repairs were made in Lino Lakes and 34 new septic systems were constructed, giving an average of 27 repaired and 4 constructed per year. A copy of the City s Individual Sewage Treatment Systems ordinance Chapter 403, as amended, is included in Appendix D. Minnesota rules chapter 7080 was amended in Minnesota counties have two years to amend their ordinance and cities have one year following the counties amendment date to update their ordinance. In accordance with the Minnesota rules chapter 7080 the City will have its ordinance updated within one year of Anoka County s update. 7-26

27 7-27

28 Intercommunity Connections An existing intercommunity connection serves 13 lots on the north side of Ash Street (County Road J) west of Hodgson Road in Sub-District 1A. These lots are served by an 8-inch lateral sewer flowing into the City of Shoreview sewer system. In addition, several homes along Sunset Avenue south of Elm Street in Sub-District 2F are served by the Blaine sewer system. The City of Shoreview has expressed interest in serving a few homes along County Road J east of Turtle Lake Road by way of future Lino Lakes sanitary sewer extensions. The proposed Lino Lakes system includes sufficient capacity for theses homes. As discussed previously, as a result of joint planning by the cities of Lino Lakes and White Bear Township, the White Bear Township sewer system has capacity available to serve Lino Lakes District 4. However, no formal agreement exists between the City and Township; this agreement should be pursued by the City. A Joint Powers Agreement between Lino Lakes and White Bear Township must be completed to ensure that this capacity remains available for Lino Lakes use. The City of Columbus has expressed interest in sanitary sewer service for a future commercial node along Lake Drive just north of the Lino Lakes border. The Metropolitan Councils 2030 Framework includes all but the extreme eastern portion of the City of Columbus in the Diversified Rural geographic planning area, where the Regional Policy 1 includes accommodating forecasted growth through 2030 without requiring the provision of regional urban services. Unless the Metropolitan Council policy towards the City of Columbus changes, sanitary sewer service cannot be extended to the northern border of Lino Lakes. If and when the change does occur, the wastewater flow capacity for the City of Columbus will need to be determined. If the sanitary sewer flow from the City of Columbus is to pass through the City of Lino Lakes the capacity allocated to the City of Lino Lakes by the Metropolitan Council will need to be re-examined. The Lino Lakes sanitary sewer system plan will also need to be re-examined to include the cost for sizing trunk lines to accommodate the City of Columbus flow. Lino Lakes has not received any information regarding regional policy or flow needs for the City of Columbus. Therefore this plan does not include service outside the borders of the City in the existing or future flow capacity projections. Infiltration and Inflow The Lino Lakes City Code Section prohibits the discharge of surface waters of any form into the municipal sewer system. Section of the City Code is included in Appendix D. The City of Lino Lakes completed a two phase inflow and infiltration study due to concerns with groundwater and surface water entering the sanitary sewer system. The first phase of the study consisted of the south half of the City and was completed in The second phase of the study consisted of the north half of the City and was completed in The inflow and infiltration study was used to prepare a plan for maintenance and capital improvement projects. The key component of the plan was to reduce inflow and infiltration through a combination of rehabilitation, maintenance and capital improvements. Infiltration typically results from defective pipes, off-set or defective joints faulty service connections or defective manholes. Inflow is generated through roof leaders, yard drains, foundation drains, sump pumps, leaky manholes and possible cross connections between the stormwater and sanitary sewer systems. The infiltration and inflow study provide a priority list of project areas that infiltration and inflow was found. In 2004 the City hired a contractor to complete the highest priority work outlined in the infiltration and inflow study. This project was estimated to remove 43,500 gallons per day of infiltration and inflow of surface waters. The public works department maintains the sanitary sewer system and has performed numerous infiltration and inflow reduction maintenance projects throughout the City in both areas outlined in the program and throughout the City. The 7-28

29 City continues to monitor the infiltration and inflow in the areas outlined in the study and throughout City by lift station pumping records and routine inspections of the sanitary sewer system by public works. Future Sanitary Sewer System The Lino Lakes Demographic Profile and Forecasts section outlines the anticipated growth and development plan for the City. This section discusses the future trunk sewer and lift station facilities that will be required to support this growth. To adequately service the projected growth and development plan, the City will need to expand the existing sewer system. A trunk sanitary sewer collection system composed of trunk sewers, lateral sewers, and lift stations will need to be incrementally constructed. A plan for future construction of proposed facilities is shown on Figure 7-5, Future Sanitary Sewer System with Utility Staging map and on Figure 7-6, future Sanitary Sewer system with Sewer District Boundaries. Design Considerations The future layout of the trunk sewer system is greatly dependent upon the existing topography of the areas to be served and the connection locations to the existing sewer system. Gravity flow sanitary sewers are the lowest cost sewer system in urban regions. This is due to their long useful service life and low costs for operation and maintenance. One of the primary design considerations is to provide gravity sanitary sewer service whenever possible and to minimize the use of lift stations. When a lift station is required, additional capital costs are incurred as well as greater operation and maintenance costs. In almost all communities, some lift stations are required as part of the integral sewer collection system. The goal is to carefully plan the overall sewer system in an effort to reduce the total number required. When a lift station is needed, it is important to identify a maximum service area based upon the surrounding topography. It is also important to minimize the forcemain length in an effort to reduce the annual energy costs to pump the sewage to the discharge location. By placing each trunk and lateral sewer at the recommended minimum pipe slope, the service area for that particular sewer is typically maximized and the number of lift stations required throughout the total system is reduced. Therefore, it was assumed that each trunk sewer in Figure 7-4 will be installed at the minimum recommended slope per Ten States Design Standards. Given the pipe size and slope, the capacity of each sewer can be determined. A second major consideration is to identify the location and available capacity of each connection point to the existing sewer system. It is typically more economical to stage growth contiguous to the existing sewer system, extending incrementally with each new development. Eventually the existing system reaches the extent of its service capabilities. Before additional growth can be added, major infrastructure improvements are then required to extend the system s service area. The sewer system layout shown on Figures 5 and 6 was carefully constructed using these design considerations. The following paragraphs summarize anticipated trunk sewer and lift station construction in each sewer service District. 7-29

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31 7-31