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8.f2 Staff Report - May 2022 Discussion on Sewer CapacitiesPage 1 of 5 City of Scandia 14727 209th St. N. PO Box 128, Scandia, Minnesota 55073 Phone (651) 433-2274 Fax (651) 433-5112 http://www.ci.scandia.mn.us DATE: May 17, 2022 TO: Honorable Mayor and City Council Members FROM: Ken Cammilleri, City Administrator RE: May 2022 Sewer Capacities Discussion The Uptown System The Uptown system currently has nine customers and serves multiple businesses within the proximity of the intersection of Oakhill Road N. and Olinda Trail N. Unlike the other two systems, Uptown remains the one system with limited documentation relating to its ultimate design. Specifically, we do not have access to any design documents that would have formally specified engineered capacity. The result of the major gap in r records left the City with a bit of a mystery as to what the system’s true designed capacity is. Records from the system’s early construction in 1995 suggests that the system first had an original design capacity of 2,460 gallons per day. The later expansions of the system to include Community Center (1,000 gallons/day) and Gammelgården (600 gallons per day) appear to be the only other times the system's capacity was increased. With these two additions, the records suggest the system could support 4,060 gallons per day. The Community Center campus originally had on-site septic. The original main system had tanks and a drainfield that was originally built to handle 500 gallons per day, but the drainfield was expanded to add another 500 gallons per when the Warming House was constructed in 1996. The Community Center was expanded in 1999 when all of the Community Center buildings were added to Uptown. Records suggest this system was periodically used for reserve/backup, but eventually fell out of use and has long since been without an active County permit. Its current condition is unknown. (The cold storage building on the Community Center campus, formerly the township’s public works building, also had its own system. It had an on-site septic and motor vehicle waste disposal well since its construction in 1972. It is also likely that this system serviced a small water closet structure located just behind this building. Records suggest that this system was briefly connected to Uptown, but the holding tank was disconnected from the system in 2012. The building was taken out of use in 2000 with the construction of the new public works facility.) (The City’s Annex Building, formerly the fire department and town hall, located 14800 Oakhill Road N is not connected to the City system. It is currently only served by an on-site septic holding tank. This may be a barrier for building code compliance should the building be improved for other purposes or sold. The current sanitary arrangement for this building can be maintained so long as there are no changes to use or occupancy.) Page 2 of 5 City of Scandia 14727 209th St. N. PO Box 128, Scandia, Minnesota 55073 Phone (651) 433-2274 Fax (651) 433-5112 http://www.ci.scandia.mn.us Uptown’s operating permit with Washington County states that this system is limited to 2,026 average gallons per day per month and a peak daily flow of 7,535 gallons. The discrepancy between the permit, the city and county records, and the current layout and design of the Uptown treatment site led both the City and County to believe that the system was at user capacity. It appears that given the uncertainty, the City had a new connection moratorium in place since the last major upgrades and improvements to the System in 2012. It was not until the Scandia Heritage Alliance recently proposed the regional arts and heritage center project that a significant effort was made to gain a greater understanding of the system’s design limitations. Based on information provided by the Scandia Heritage Alliance, the City Engineer has been able to estimate usage demand by the Arts and Heritage Center based on the operational contingency that on site restrooms are replaced with portable toilets during large events. 215 gallons per day would be the projected average use with a peak daily flow of 800 gallons. It is believed that the system could support this use strictly on the condition that portable toilets are only used during large events. The Arts and Heritage Center will be the last permit that can be issued for connection to this system until its treatment capacity is increased. Based on estimates from the City Engineer, we now suspect that peak daily system flows are more likely around 5,000 gallons. Average system use fluxuates between 3,000 gallons per day to 3,200 gallons per day. Higher flows have been around 3,500 gallons per day. Estimated costs for expanding the system will depend on the extent of additional service that the City wishes to address. To add some perspective a two bedroom home would require 300 gallons/day capacity. Additional commercial uses may exceed this minimum depending on the use and the quantity of visitors. An adjacent property was acquired in the late 2000 of 4.85 acres which could be used to build out an new system. There is limited area on the current site to add additional drainfield capacity. The Anderson-Erikson System (eastern shore of Big Marine Lake) The Anderson-Erickson System currently serves 33 homes on Norell Avenue N and the eastern end of 188th Street N with a maximum treatment design of 6,700 gallons per day. The system is currently licensed for operation by Washington County for an average flow of 5,025 gallons per a day per month. The peak flow is 8,600 gallons per day. Average daily gallons per day hover around 3,000 gallons per day to 4,600 gallons per day at peak. (Some daily peak flows have exceeded its 5,025 GPD limit.) The current drainfield system has 3 cells with the intent that only 2 cells would be dosed at any time with one cell in rest. This system may only have room for one additional drainfield cell before it will be limited by the property’s limited size. The system only has one lift station that feeds directly to the drainfield. Page 3 of 5 City of Scandia 14727 209th St. N. PO Box 128, Scandia, Minnesota 55073 Phone (651) 433-2274 Fax (651) 433-5112 http://www.ci.scandia.mn.us The system had its controls updated fairly recently and its service lines were only expanded in 2002 to include the eastern portion of 188th Street N. The system, based on its age, may be experiencing inflow and infiltration (I&I) as fluctuation of flows have been observed during periods of significant rainfall. Given this system is currently under a new connection moratorium to prevent the system from being overdosed and from exceeding its permitted limits. New connections are limited and replacement of homes must maintain the same number of existing bedrooms to obtain a connection permit. This system will likely require at least a drainfield expansion to keep it from approaching any of its limits. As the remaining seasonal houses are shifted to permanent year-around residency, the system risks approaching capacity limits. Expansion including land acquisition would be needed in order to add additional shoreland properties into the system. The expansion need is not imminent, but should not be ignored. The City will need to monitor changes in flow activity closely to implement more stringent connection moratoriums. This system has a substantial list of deferred improvement projects that will need to be addressed in the years to come. Depending on the extent of system expansion, environmental assessment worksheets may be required along with Federal National Pollutant Discharge Elimination System (NPDES) and State Disposal System (SDS) permits at 10,000 GPD. The Bliss System serving the western shore of Big Marine Lake The Bliss Wastewater Collector serves approximately 80 households within a defined service area that predominantly services the Bliss Addition Neighborhood, but not the entirety of it. The facility processes around 7,000 gallons/day in winter and over 11,000 gallons/day in wet summer months. The total designed capacity is said to be 19,800 gallons per day. The system is the largest of the three systems owned by the City and is the only one that requires NPDES and SDS permits. The distribution system has 4 lift stations, 3 sand filter units for the capture of solids, and 3 unit drainfield that is intended to dose only two cells at a time with one at rest. The system also has holding tanks and a combination of pressurized sewer mains and gravitational mains. This system also has a substantial list of deferred improvement projects that will need to be addressed in the years to come including its impending $1,000,000 nitrate treatment project scheduled for 2023. This system does have available service capacity, but the City should determine if this system may have an expanded service area in the future or not as this cost should be factored into the calculation of sewer area connection fees. Page 4 of 5 City of Scandia 14727 209th St. N. PO Box 128, Scandia, Minnesota 55073 Phone (651) 433-2274 Fax (651) 433-5112 http://www.ci.scandia.mn.us Funding Options for A/E and Uptown The City’s next steps for planning for the future of its wastewater treatment systems should include estimating the costs of necessary and projected improvements that are based on its plans for service coverage. All of the systems should have a revised sewer area connection fee that reflects the anticipated cost of system upgrades based on an anticipated buildout that factors in reasonable inflationary projections. We should also make sure that we also institute a residential equivalent unit to determine connection costs that reflects year-around residence, number of bedrooms, and baths. Obtaining any possible funding from the state can be relatively limited. Here are the options available to us: · State bonding remains a potential option, but requires getting the legislature to include it within its capital bonding process in even years. Matches are generally expected with 50% as customary. We are hoping this becomes a reality with the Bliss Wastewater Nitrate Treatment Project. Legislators often expect that a project be on the State’s Project Priority List (PPL) that is updated yearly by the Public Facilities Authority (PFA) based on rankings made by the Minnesota Pollution Control Authority (MPCA). Placement on the PPL requires the completion of a MPCA facilities plan. · The PPL is ranked by points scored and can open eligibility to low interest PFA loans over a 20 year term over a set interest rate. Scoring can be increased if improvements address environmental problems such as failed onsite systems, surface eruption of septic tank effluent, lack of adequate well separation, etc. · The Small Community System Wastewater Treatment Grant Program through PFA and MPCA, includes funding for technical assistance of $60,000 and $2 million for construction projects. However, this program also has the requirement that Median Household Income of the area served must be less than the State’s Median Household Income (MHI). The State’s MHI in 2020 was $73,382. Scandia’s 2020 MHI was around $84,700. We are not likely eligible for any state grants except through bonding requests, unless it addresses point source water quality like with Bliss. This limitation will prevent the City from obtaining other federally sourced grant funding. · Lending opportunities are available through the issuance of bonds, the Minnesota Rural Water Association, and the State’s PFA, as mentioned. · Use of Tax Increment Districts can only be utilized for new residential developments that benefit low to moderate incomes. Page 5 of 5 City of Scandia 14727 209th St. N. PO Box 128, Scandia, Minnesota 55073 Phone (651) 433-2274 Fax (651) 433-5112 http://www.ci.scandia.mn.us Next Steps The City will need to consider whether or not it intends to seek expansions of these systems. New rate structures and Sewer Area Connection fees will be shaped by these plans and capital improvement needs. The goal of this presentation is to provide an education on the current sewer capacities and use, so that thoughtful decisions can continue to be made in the stewardship of these systems and members of the public can better understand the City’s sewer utilities. Please let me know if you have any questions.