DEPARTMENT OF ENVIRONMENTAL QUALITY

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3 PROJECT IDENTIFICATION DEPARTMENT OF ENVIRONMENTAL QUALITY City of Burton Sanitary Sewer Collection System Improvements State Revolving Fund (SRF) Environmental Assessment April 2015 Applicant: Authorized Representative: Address: City of Burton, Genesee County Mr. Gregory Kray, Director Public Works 4303 S. Center Road Burton, Michigan SRF Project No.: PROJECT-IN-BRIEF The city of Burton, situated near the center of Genesee County immediately southeast of the city of Flint, owns and operates a sanitary sewer collection system (see Figure A), which transports wastewater from Burton to a regional wastewater collection and treatment system operated and maintained by the Genesee County Drain Commission (GCDC). Burton s sanitary sewer system consists of a network of over 179 miles of sewer pipes (gravity and force mains) ranging in size from 6 to 27 inches in diameter and 10 sanitary pump stations. Burton is applying for loan assistance from the state of Michigan s SRF to finance the following capital upgrades and improvements (see Figure A) to its sewer system: of Casto, Cheryl Ann, Farner, Leith, and Rinn Pump Stations and force mains. Lining and replacement of approximately 10,000 linear feet of gravity sewer that was recently evaluated with a Pipeline Assessment Certification Program (PACP) structural rating of Poor (Grade 4) or Immediate Action (Grade 5). of an estimated 6,500 linear feet of 15-inch-diameter gravity sewer along Atherton Road from Center Road to Connecticut Street with 18-inch pipe and replacement of the associated 22 access manholes. The total project cost estimate is $6.7 million. Construction will begin in the fall of 2015 and end by the fall of The SRF loan will have a 20-year term at a 2.5-percent interest rate. User rates will increase to repay the SRF loan debt. There are two types of residential customers: metered and non-metered. Those metered are charged a rate based upon actual water usage and those non-metered are charged a set fee since their water usage is not measured. The estimated annual rate increase to the typical residential user as a result of the project will be $42 for metered customers and $38.28 for non-metered customers. Burton received State Revolving Fund/Strategic Water Quality Initiatives Fund (S2) grant funding in 2013, which was used to pay for related planning costs and will reduce the SRF loan amount by $706,226. 1

4 Table I identifies the present and projected 20-year forecast for the population of Burton and the average daily flow in million gallons per day (MGD) for Burton s sanitary sewer system. Table I City of Burton Present Projected 20-year Forecast Population 29,432 33,164 Average Daily Flow (in MGD) Over the next 20 years, the population is expected to increase by 12.7 percent, while the average daily flow for the sewer system is predicted to increase by 6.5 percent. PROJECT NEED Much of Burton s sanitary sewer collection system was built in the mid-to-late 1960s. Many component facilities have not been updated in the last 33 to 45 years. Five sanitary pump stations (Casto, Cheryl Ann, Farner, Leith, and Rinn) and their associated force mains have all exceeded their recommended design service lives. The Casto, Farner, and Rinn Pump Stations were built in 1969, while the Leith and Cheryl Ann Pump Stations were built in 1978 and 1981, respectively. These pump stations also require the addition of onsite natural gas generators and automatic transfer switches for emergency backup power as well as various improvements to the Supervisory Control and Data Acquisition (SCADA) system. The force main related to the Casto, Cheryl Ann, and Rinn Pump Stations were built in 1969, while the force main related to the Leith and Farner Pump Stations were built in 1978 and 1981, respectively. The force main associated with the Farner Pump Station has experienced two failures (i.e., pipe breaks) over the past four years (one in 2011 and one in 2014), each prompting an emergency repair. Many of the gravity sewers were constructed about 50 years ago. A recent structural integrity investigation has identified approximately 10,000 linear feet of pipe with a PACP rating of either Poor (Grade 4) or Immediate Action (Grade 5). A PACP rating of Poor (Grade 4) means the defect(s) is severe and will likely fail within the next 5 to 10 years and in the interim will soon become Immediate Action (Grade 5). Meanwhile, a PACP rating of Immediate Action (Grade 5) means the defect(s) requires prompt attention and if not addressed, will likely fail within the next five years (if it has not already). An estimated 6,500 linear feet of 15-inch-diameter trunk line gravity sewer along Atherton Road from Center Road to Connecticut Street needs to be replaced with 18-inch pipe to meet design storm capacity requirements for minimum freeboard depth. The 22 manholes used for access to the Atherton Road gravity sewer must also be replaced since each manhole will need an 18-inch boot connection installed. ANALYSIS OF ALTERNATIVES No-Action The no-action alternative would result in the continued deterioration of the above identified aged component facilities in Burton s sanitary sewer collection system. If action is not taken to address these system needs, over time periodic failures to these pump stations, force mains, and gravity sewers would likely be the consequence along with interruptions in service and impacts to the environment. Thus, the no-action alternative was rejected outright. 2

5 Principal Alternatives The present worth analysis is used to evaluate the principal alternatives based upon costeffectiveness and is shown in Tables II through VI. Total present worth is calculated by subtracting present worth of salvage from total capital cost and adding present worth of operation, maintenance, and replacement (OM&R) costs. The fiscal year 2014 discount rate is percent. Straight line depreciation over 20 years was utilized to calculate salvage values. 1. Can Type Pump Stations (Casto, Cheryl Ann, Farner, and Rinn) Principal Alternatives a. Upgrade Can Type Stations Using Existing Steel Can Alternative No. 1a includes replacement of pumps, piping, and valves. The new pumps would handle solids. The new isolation valve configuration would be for plug valves. Pipe replacement would be done for the new pumps and valves. Steel can structure repairs would be done to address spots, thinning, leaks, corrosion, and rust, along with an industrial epoxy coating for repainting. b. Replace Can Type Stations with Submersible Type Using Existing Wet Well Alternative No. 1b includes abandoning the steel can structure, removing all equipment from the chamber, and filling it with flowable fill. The wet well would be lined and submersible pumps added with base elbows, guiderails, brackets, discharge pipe, and a new precast concrete valve vault with new valves. Table II Present Worth Analysis of Principal Alternative Nos. 1a and 1b Can Type Pump Stations (Castro, Cheryl Ann, Farner, and Rinn) Alternative No. 1a Upgrade Can Type Using Steel Can (New Wet Well) Alternative No. 1b Replace with Submersible Type Using Existing Wet Well (Reinforcement Required) Total Capital Cost $2,208,750 $2,223,750 Present Worth of OM&R $374,776 $374,776 Total Present Worth $2,583,526 $2,598,526 Note: Present worth of salvage for both alternatives is $0. Chosen Alternative for Can Type Pump Stations (Casto, Cheryl Ann, Farner, and Rinn) Table II displays Alternative No. 1a, Upgrade Can Type Using Steel Can (New Wet Well), as the cost-effective option to address the needs of the Can Type Pump Stations (Casto, Cheryl Ann, Farner, and Rinn). Therefore, Burton is including Alternative No. 1a in the selected alternative. Chosen Alternative for Submersible Pump Station (Leith) is the only available option to address the needs of the submersible pump station at Leith. The existing wet well cannot be reused since it is inadequately sized to meet current design standards; so the Leith submersible pump station requires a new wet well. As a result, there is no present worth analysis for the Leith submersible pump station. The total capital cost for the work is $455,000. The pumps, piping, and valves for the Leith submersible pump station will all be replaced. Installation within the wet well will include the submersible pumps, base elbows, guiderails, brackets, discharge pipes, and valves. The new pumps will handle solids. 3

6 The new isolation valve configuration will be for plug valves. Pipe replacement will be done for the new pumps and valves. Concrete structure repairs will be done as needed. 2. Gravity Sewers with a PACP Structural Rating of a Grade 4 or 5 Principal Alternatives a. Maximize Feasible Pipe Rehabilitation (Lining) and Replace Where Necessary Alternative No. 2a utilizes where feasible cured-in-place pipe rehabilitation (lining) for the gravity sewers with a PACP rating of a Grade 4 or 5 and limits pipe replacement to the sections deemed as collapsed with no possibility of lining. This option consists of approximately 8,450 linear feet of lining and 1,550 linear feet of replacement. b. Pipe Only Alternative No. 2b would consist of replacing all estimated 10,000 linear feet of gravity sewer identified with a PACP structural rating of a Grade 4 or 5. Table III Present Worth Analysis of Principal Alternative Nos. 2a and 2b Gravity Sewers with a PACP Structural Rating of a Grade 4 or 5 Alternative No. 2a Maximize Pipe Rehabilitation with Where Necessary Alternative No. 2b Pipe Only Total Capital Cost $1,321,943 $2,841,815 Present Worth of OM&R $131,171 $131,171 Present Worth of Salvage Value $336,848 $724,131 Total Present Worth $1,116,266 $2,248,855 Chosen Alternative for Gravity Sewers with a PACP Structural Rating of a Grade 4 or 5 Table III indicates that Alternative No. 2a, Maximize Rehabilitation (Lining), is the cost-effective option to address gravity sewer structural integrity needs. Therefore, Burton is including Alternative No. 2a in the selected alternative. 3. Force Mains (Casto and Rinn) Principal Alternatives a. Casto and Rinn Force Main Rehabilitation (Lining) Only Alternative No. 3a would consist of cured-in-place pipe rehabilitation (lining) only. b. Casto and Rinn Force Main (Open-Cut Construction) Only Alternative No. 3b would consist of replacement by open-cut construction only. c. Casto and Rinn Force Main (Directional Drill Construction) Only Alternative No. 3c would consist of replacement by directional drill construction only. 4

7 Table IV Present Worth Analysis of Principal Alternative Nos. 3a, 3b, and 3c Force Mains (Castro and Rinn) Alternative No. 3a Rehabilitation (Lining) Only Alternative No. 3b (Open-Cut) Only Alternative No. 3c (Directional Drill) Only Total Capital Cost $194,375 $256,663 $192,919 Present Worth of OM&R $6,181 $6,181 $4,589 Present Worth of Salvage Value $49,530 $65,401 $49,159 Total Present Worth $151,026 $197,443 $148,349 Chosen Alternative for the Force Mains at the Casto and Rinn Pump Stations Table IV indicates that Alternative No. 3c, (Directional Drill) only, is the costeffective option to address the needs of the Casto and Rinn Pump Station force mains. Therefore, Burton has chosen Alternative No. 3c for inclusion in the selected alternative. 4. Force Mains (Farner and Leith) Principal Alteratives a. Farner and Leith Force Main (Open-Cut Construction) Only Alternative No. 4a would consist of replacement by open-cut construction only. b. Farner and Leith Force Main (Directional Drill Construction) Only Alternative No. 4b would consist of replacement by directional drill construction only. Table V Present Worth Analysis of Principal Alternative Nos. 4a and 4b Force Mains (Farner and Leith) Alternative No. 4a (Open-Cut) Only Alternative No. 4b (Direction Drill) Only Total Capital Cost $588,128 $404,553 Present Worth of OM&R $15,977 $15,977 Present Worth of Salvage Value $149,863 $103,085 Total Present Worth $454,242 $317,445 Rehabilitation (lining) is not a feasible alternative for addressing the needs of the force mains associated with the Farner and Leith Pump Stations. The Farner force main has experienced two failures (i.e., pipe breaks) within the past four years; so rehabilitation (lining) is not advised. The technical feasibility of lining the Leith force main was questioned as a result of its small size (4 inches in diameter) and so only replacement options were evaluated further. Chosen Alternative for the Force Mains at the Farner and Leith Pump Stations Table V establishes Alternative No. 4b, (Direction Drill) only, as the cost-effective alternative to address the needs of the Farner and Leith Pump Station force mains. Therefore, Burton has chosen Alternative No. 4b as a part of the overall selected alternative for the project. 5

8 5. Force Main (Cheryl Ann) Principal Alternatives a. Cheryl Ann Force Main Rehabilitation (Lining) Only Alternative No. 5a would consist of cured-in-place pipe rehabilitation (lining) only. b. Cheryl Ann Force Main (Open-Cut Construction) Only Alternative No. 5b would consist of replacement by open-cut construction only. c. Cheryl Ann Force Main (Directional Drill Construction) Only Alternative No. 5c would consist of replacement by directional drill construction only. Table VI Present Worth Analysis of Principal Alternative Nos. 5a, 5b, and 5c Force Main (Cheryl Ann) Alternative No. 5a Rehabilitation (Lining) Only Alternative No. 5b (Open-Cut) Only Alternative No. 5c (Directional Drill) Only Total Capital Cost $48,000 $46,944 $51,863 Present Worth of OM&R $395 $158 $395 Present Worth of Salvage Value $12,231 $11,962 $13,215 Total Present Worth $36,164 $35,140 $39,043 Chosen Alternative for the Force Main at the Cheryl Ann Pump Station Table VI indicates that Alternative No. 5b, (Open-Cut), is the cost-effective option to address the needs of the Cheryl Ann Pump Station force main. Therefore, Burton has chosen Alternative No. 5b for inclusion in the selected alternative. 6. Trunkline Gravity Sewer (Atherton Road) The existing 15-inch trunk line gravity sewer along Atherton Road between Center Road and Connecticut Street is undersized based upon current design storm capacity requirements independent of any issue Burton s sanitary sewer collection system may have with infiltration and inflow (I/I) contribution. I/I is the combination of groundwater and rainwater entering a collection system through cracks and openings in pipes and manholes. If excessive during wet weather events (i.e., storms and snow melts), I/I may result in surcharging, basement backups, or even overflows. Sewer surcharging alone is not necessarily a problem, but if in excess of freeboard depth requirements, surcharging would be above basement levels, and the flooding of basements is a clear public health hazard. Within the context of the modeled intensity and duration of a 25-year/24-hour design storm event, the existing 15-inch Atherton Road gravity sewer is undersized to meet minimum freeboard depth requirements. Even if all or most of the I/I were removed, sewer surcharging would still occur and sufficient capacity would still not exist inside this sewer pipe. The only available option to address this problem is to replace the existing 15-inch Atherton Road gravity sewer with an 18-inch pipe. The project cost estimate is $2.37 million. For a cost-effectiveness comparison, both sewer replacement in place and parallel sewer alignment will be considered during the design phase of the project. 6

9 ENVIRONMENTAL IMPACTS The proposed sanitary sewer lining and replacement work will all take place at the location of the respective existing sewers. Much of these sewers are situated within the existing rights-ofway with the remainder positioned within easements traversing vegetated fields, woodlands, or wetlands. The proposed sanitary sewer pump station upgrades and replacement work will all be limited to the location of these existing structures. A wetland delineation report was completed, and the appropriate mitigation techniques to protect any wetlands identified within the construction area of influence will be incorporated into the final design. The project construction will require a Michigan Department of Environmental Quality (DEQ) land and water management permit under Part 31, Water Resources Protection, and Part 303, Wetlands Protection, of the Natural Resources and Environmental Protection Act, 1994 PA 451, as amended (NREPA). The State Historic Preservation Office issued a clearance (File No. ER98-145) indicating no historic properties will be impacted. The Native American Tribal Historic Preservation Office (THPO) contacts were given an opportunity to comment and will receive a notice with a website link to this Environmental Assessment. Two THPO contacts provided comments, both confirming they are unaware of any historic, religious, and/or culturally significant resources that may be impacted by the project. It was determined that the project will have no effect on federally listed species identified by the United States Fish and Wildlife Service, either directly or to respective habitat. The Michigan State University, Michigan Natural Features Inventory, advised it is not likely that negative impacts will occur to state listed species since the natural heritage database has no record of any legally protected species documented within 1.5 miles of the project site. Direct impacts resulting from the implementation of the selected alternative will include noise, dust, and construction traffic. Noise will be kept from disturbing residents as much as possible by the restriction of allowable work hours. Dust control activities will also be undertaken. With the proper implementation of soil erosion and sedimentation control measures, the quality of local surface waters should not be impacted. A permit pursuant to Part 91, Soil Erosion and Sedimentation Control, of the NREPA, will be issued by the county. Since work will take place in the road rights-of-way, traffic control and safety measures will be implemented. Most work will occur in residential areas with only minor traffic control measures being necessary, while access to dwellings will be secured. Secondary Growth The selected alternative includes replacement of an existing 15-inch trunk line gravity sewer along Atherton Road with 18-inch pipe since it is undersized based upon current design storm capacity requirements for minimum freeboard depth. The 18-inch pipe is necessary to prevent surcharging of wastewater above basement levels up to the 25-year/24-hour design storm event. Since the proposed 18-inch gravity sewer is designed specifically to resolve the clear public health hazard of basement flooding, it is not anticipated to facilitate and/or accommodate any projected growth over the 20-year planning period or create any secondary impacts. PUBLIC PARTICIPATION The public hearing on the project plan was advertised in the Burton View on May 15, The project plan was available for public inspection at Burton City Hall on 4303 S. Center Road in Burton. The public hearing was held at 6 p.m., on June 16, A resolution adopting the 7

10 project plan and designating an authorized project representative was approved by the Burton city council after the public hearing on June 16, REASONS FOR CONCLUDING NO SIGNIFICANT IMPACT The selected alternative includes sanitary sewer lining and replacement as well as pump station upgrades and replacements. The work is necessary since the facilities are either at the end of their recommend useful design lives (if not already exceeded them) or undersized. Secondary growth impacts are not anticipated. Mitigative measures will be taken to minimize any shortterm adverse construction impacts such as noise, dust, fumes, traffic, and soil erosion. Questions regarding this Environmental Assessment should be directed to: Ms. Sonya T. Butler, Chief Revolving Loan Section Office of Drinking Water and Municipal Assistance Michigan Department of Environmental Quality P.O. Box Lansing, Michigan Telephone:

11 City of Burton Sanitary Sewer Collection System Improvements FIGURE A 9