Table of Contents. Page Title Sheet and Index Project History and Summary Work Summary Overview 3-7

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1 Summary Final Report EPA Assistance ID Number: XP-00E : Excess Flow Reduction Efforts Evergreen Farmington Sewage System Manhole Rehab and Sewer Lining Table of Contents Page Title Sheet and Index 1 1. Project History and Summary Work Summary Overview 3-7 A. Planning and Study Phase Recommendations B. Design Plans and Specs 5 C. Bidding and Award.. 6 D. Construction. 6 E. Additional CCTV Fieldwork & Recommendations Project Issues.. 7 A. Scheduling / Scope of Work Adjustments 7 B. Rehabilitation Performed by City of Southfield with their own funds Project Schedule and Cost Summary Environmental Benefits to the Rouge River I & I Reduction Results List of Appendices Appendix Item Title A.Manhole Inspection Technical Memo B.Smoke Testing Technical Memo C.CCTV Technical Memo D.Manhole Rehabilitation Listing & Maps E.Ad For Bid, Bid Award Letter F.Photos of Manhole Rehabilitation Activities G.Construction Certification H.Additional CCTV Fieldwork and Recommendations (Districts 3260, 3220) I..Project Data Files Page 1

2 1 Project History and Summary The Project involved planning, design, and construction activities to investigate and remove excess I & I from the sanitary sewer system within the City of Southfield. The Project was funded through a City/County collaborative effort involving two (2) separate grant programs with respective local match funds. The planning and study phases of the Project were funded through an RPO Grant (RXA-05) obtained by the City of Southfield from the Wayne County Rouge Program Office. The CCTV inspection, design, and construction services were funded through EPA Grant XP-00E and administered through the Oakland County Water Resources Commissioner s (OCWRC). In addition, the City is funding portions of the sewer repair work recommended from CCTV investigations as part of ongoing or future planned City sewer rehabilitation projects. The Project was needed because the Evergreen-Farmington Sewage Disposal System (EFSDS) experiences excessive flow at various times during wet weather conditions. Reduction of this excess flow can be helpful in reducing the sanitary sewer overflows in the collection system, which is a source of pollution to the Rouge River. This project further expands the ongoing efforts by Oakland County to manage sanitary flows within the EFSDS by identifying sources of excess flow, designing site specific repairs, and selecting contractors to complete repairs, thereby implementing flow reduction and associated SSO elimination in the Evergreen-Farmington Sewage Disposal System. The City of Southfield, lies within the Main 1-2 Sub Watershed Management Plan of the Rouge River, in Oakland County. Approximately 90% of the City s sanitary flows are serviced by the Evergreen-Farmington Sewage Disposal System (EFSDS). The EFSDS is an older system with a history of sanitary sewer overflows and is completely contained within the Rouge River Watershed. Based on meter data from the EFSDS meters measuring flows from the City of Southfield, there are a number of sanitary sewer sub-districts within the City that have experienced excessively high wet weather flows. Sub-districts with high I/I flows were identified by considering their peak flow (inflow) response to large storm events. Peak wet weather flows for some of the sub-districts under consideration averaged 646 gpcpd, significantly higher than the EPA standard of 275 gpcd. Additional sub-districts of known problem areas were added to the field investigations based on discussion with the City of Southfield engineering and DPW staff, Oakland County, and Wade-Trim. A map of the final areas included in the study is shown on Figure 1 Page 2

3 Figure 1 Study Area District Location Map A collaborative effort between the City and County staff and their respective engineering consultants and outside contractors optimized the use of available resources to prioritize investigations and maximize I/I repairs within available grant budgets. Meter data was used to focus the initial field effort, and the approach was adjusted as needed to manage the budget as conditions were encountered in the field. 2. Work Summary Overview: A. Planning and Study Phase Recommendations The field investigations were primarily completed in 2011 under the RPO Grant. Field findings were compiled and evaluated by Wade-Trim engineering staff to develop and identify rehabilitation recommendations. In February to April of 2012, several meetings were held with Southfield and Oakland County to review the fieldwork findings from smoke testing, manhole Page 3

4 inspections, and Initial CCTV activities, and review the rehabilitation recommendations. The following summarizes the results from each field task. Manhole Inspection Findings / Recommendations The purpose of this evaluation was to inspect manhole conditions, recommend rehabilitation needs, and estimate the potential quantity of inflow from identified defects. Of the approximately 1200 manholes which were inspected, 590 were recommended for rehabilitation. These manholes were in fair to poor condition, and had specific defects noted by the field crews or evidence of I/I indicated on the inspection forms. A cost-effectiveness analysis was performed on the manholes recommended for rehabilitation, by estimating the cost of rehabilitating the manhole to eliminate I/I vs. the cost of transporting and treating the estimated volume of I/I over a 20 year period. Recommended manhole rehabilitation measures included the following: 1) Replacement of manhole covers in areas susceptible to surface runoff (boltdown, gasketed covers in roadway areas, and solid, gasketed covers in greenbelt areas), 2) Installation of internal flexible seals (aeromatic urethane product) to eliminate inflow from entering the manhole from beneath the frame or in defects in the ring, and 3) Plugging leaks in the manhole cone, wall, or bench where there was evidence of infiltration. The detailed recommendations are summarized in a Manhole Inspection Technical Memo included in Appendix A. Smoke Testing Findings / Recommendations The purpose of this evaluation was to assemble the field data and provide it to the City so that corrective action measures which the City can undertake could be formulated and discussed. The corrections were not completed as part of this grant, but are to be addressed separately by the City of Southfield. Seven illicit area drain connections were found in private parking lots. Approximately 50 smaller defects were found on private residential sewer cleanouts. The pictures and addresses of these locations were documented and given to the City of Southfield for enforcement action by the Southfield DPW and building department. The detailed recommendations are summarized in a Smoke Testing Technical Memo included in Appendix B. The rational formula was used to estimate the inflow contribution of the defects found. A breakdown of these estimates by sub-district is provided, in Table 1. Video Inspection Tape Review The purpose of this task is to perform internal CCTV inspections of the sanitary sewer network. The video inspections were conducted in districts identified as having I/I issues. Approximately 60,000 l.f. of sanitary sewer was cleaned and televised. CCTV in Area 3010 was performed in April through July This work preceded the work activities covered in the RPO grant. CCTV and cleaning in two Page 4

5 priority Districts (Districts 3110 and B) were added based on discussions with the City DPW and Engineering Staff. One was an area which was previously combined and had the highest system peak rates as evidenced by prior system flow monitoring data, and a second was an area which the City had experienced prior basement flooding. The tapes were reviewed by Wade-Trim NASSCO certified staff to identify the observed defects. The defects were evaluated to determine their potential to contribute I/I. CCTV tapes were transmitted to the City of Southfield. CCTV Inspection Findings / Recommendations Several runs of pipe in area 3110 were in poor condition and pipe-bursting and CIPP slip-lining were recommended. The City added this work to its list of capital improvement projects, and is currently working on lining the sewers in this area, including pipe defects identified in areas B, and The repairs are being funded separately outside the grant program. The detailed recommendations are summarized in a CCTV Inspection Technical Memo included in Appendix C. B. Design Plans and Specs To optimize use of available funds, it was decided that the manhole repairs would be bid out under the EPA contract and the City would pursue the sewer repairs under separate City capital improvement programs. The manhole repairs provided the greatest estimated peak rate reduction in comparison with the sewer pipe defects. Construction Products/Methods Used: Cover Repairs In greenbelt areas where missing bolts in manhole lids allowed surface water to enter the structure, the manhole covers were replaced with solid gasketed covers for ease of future maintenance. Bolt-down gasketed covers were specified for use in roadway areas which were subject to inflow. Frame and Ring Repairs Most manholes were precast concrete with brick adjusting rings and bolt down covers with the bolts missing. Top portion of manholes are subject to freeze thaw action and when present in low lying areas are subject to inflow from surface water during wet weather. An aeromatic urethane product was specified for chimney seal repairs because it is flexible enough to withstand the movement which occurs during freeze thaw cycles and effectively seal the chimney area from inflow. The flex-seal product was specified due to its elongation and tensile strength properties, and verifiable track record of performance in cold weather climates. Six manholes which were recommended for rehabilitation could not be rehabilitated by internal methods because the frame was offset too far from the ring. These defects were corrected by resetting the frame and cover. Page 5

6 Cone and Wall Repairs Where manholes were constructed entirely of brick and required rehabilitation, the entire manhole was lined using an epoxy manhole liner. Where defects were identified in precast manhole cone and walls, the leaks were plugged by using a quick setting cementitious material or chemical grouting as required. A schedule listing for manhole rehabilitation was developed which included the manhole GIS ID number, the district in which the manhole was located, the manhole material and depth, and the rehabilitation pay items which were to be applied to each manhole. Location maps indicating the location of each manhole to be rehabilitated were also developed. These maps were used to obtain construction permits for manholes which were to be rehabilitated in State or County road right-of-way. These items were also included in the construction contract which was prepared in April May 2012, and put out for competitive bids. The manhole rehabilitation listing and maps are included in Appendix D. C. Bidding and Award The ad for bid was placed in late May and bids were received on June 25, Nine bids were submitted. Five bids were below the Engineer s Estimate of $740,000. The apparent low bidder withdrew their bid due to an error on their part, and the project was awarded to Advanced Underground Inspection LLC for $525,335, in July The ad for bid, recommendation for award letter, and bid tabulation are included in Appendix E. D. Construction Manhole Rehab Contract A preconstruction meeting for the Manhole Rehabilitation Project was held on July 24 th, and the Contractor was given notice to proceed. The manhole rehabilitation repairs were completed by October 31, Approximately 100 manholes which were rehabilitated were located on private property. Oakland County notified residents in advance of construction with a letter providing information about the project and contact information so property owners had a point of contract with the County if they had concerns or issues. These advance notifications also aided the Contractor in obtaining timely access to the manholes for rehabilitation. Due to construction on Lasher Rd, some manholes which were on the list for rehabilitation could not be completed during this construction season. To utilize the flex seal kits which were already purchased by the Contractor, 15 manholes in area 3200, also in need of chimney seal repairs, were rehabilitated using the flex-seal kits. Page 6

7 E. Additional CCTV Fieldwork and Recommendations Due to the favorable bids received, the City of Southfield requested that the remaining grant money be used to fund additional CCTV investigations. These investigations were targeted in the remaining districts which had the highest peak wet weather flow rates, This includes additional CCTV Inspections within areas 3220, 3260, area C, and portions of area The findings from this additional field work will be evaluated and reported to the City in a future technical memorandum to be completed under the EPA grant. 3. Project Issues A. Scheduling / Scope of Work Adjustments Due to scheduling concerns regarding the EPA grant, CCTV investigations had been initiated within District 3010 prior to field activities under the RPO grant. Several meetings were held with the City of Southfield and Oakland County staff to review available information and finalize the work plan approach for prioritizing the subsequent field investigations. A memorandum dated October 4, 2011 was sent to Wayne County outlining a finalized work plan for the Project. This included a proposal to amend the original scope of work by deleting manhole inspection and smoke testing of area 3010, and adding manhole and smoke testing of areas B, and C. Area 3010 was deleted because it is the lowest priority of the other metered areas, and because it had been previously addressed with CCTV inspection and sewer lining projects by the City. Areas B, and C were added based upon reports of sewer backups and basement flooding in these areas. Night Time metering was also deleted because CCTV inspections had already been initiated and priorities established based upon city staff knowledge of the sewered areas and available flow meter data. No additional field investigations were performed in Area A under the grant, however, Southfield s DPW had identified known manhole repairs required from previous field inspections, and these repairs were included as part of the improvement recommendations. B. Rehabilitation Performed by City of Southfield with their own funds Footing Drain Sewer Disconnection One of the unique aspects of the project, was the discovery of a 6-inch sewer which conveys flows from footing drains to the Guy Street Pump Station located in sewer sub-district Manhole Inspections revealed that continuous flow of clear water was entering MH SaS7093 from a hole in the apron at the base of the manhole. The finding was referred to the City of Southfield DPW for further investigation. The City of Southfield DPW Page 7

8 confirmed via dye testing that the homes in this area had two separate private laterals, one to convey sanitary flow to the sanitary sewer, and a separate deeper service lateral to convey flow from the footing drains which surround the residence to a separate, deeper 6-inch pipe which runs in the R.O.W to the Guy Street Pump Station. Sanitary MH SaS7093 was constructed over this sewer, and because of a blockage in this 6-inch dia footing drain line downstream, it is believed that flow entered this sanitary manhole (See Sketch Below). The Southfield DPW fixed the blocked 6-inch footing drain pipe and installed manholes on the line so that it can be maintained in the future. Collaborative Review to Optimize Use of Grant and City Funds Collaborative review and joint decisions were made throughout the project to optimize resources working within the schedule and budget constraints for the two grants, and the City s ongoing sewer rehabilitation programs. As mentioned previously, because the estimated costs were large, the City of Southfield had decided to fund on their own the sewer rehabilitation in area Page 8

9 4. Project Schedule and Cost Summary Below is a table summarizing the work activities performed under the EPA grant, and the final schedule dates. To maximize the use of the EPA grant funding, and some of the ongoing CCTV work activity will be carried into next year. The estimated amount of this work and the final construction contract cost are shown on the Table 1 below: Table 1 Project Schedule and Cost Summary Task Schedule Dates Sewer District(s) CCTV L.F. MH Rehab # EPA Grant Cost $ Oakland Co. EPA Grant 174, $1,250,000 Initial CCTV Fieldwork (By Oakland Co.) April, Oct, , 3110,B, 73,000 $186,000 Initial CCTV Review & Recommendations (WTA) Aug - Jan, , 3110,B, $44,000 Design Plans and Specs Feb - May, 2012 $94,000 Bidding & Award June-July, 2012 $56,000 Construction (MH Rehab) Aug - Oct, , 3200, 3260, 3220, 3210, 3120, 3000, B, C, A 616 $609,000 Additional CCTV Fieldwork (By Oakland Co.) July - Nov, , 3260, C 48,000 $105,000 Additional CCTV Review & Recommendations (WTA) Oct, Nov, , 3260, C $27,000 Final EPA Grant Report Nov, 2012 $23,000 Estimated Additional CCTV Fieldwork, Review, & Recommendations (Oakland Co, WTA) Nov ,000 $106,000 Page 9

10 5. Environmental Benefits to the Rouge River This project benefitted the Rouge River by developing a strategy for removal of sources of clear water inflow and infiltration into the City of Southfield s sanitary sewer system, thereby reducing the flow and wet weather peaks into the sanitary sewers. These wet weather sources can contribute to SSO s in the EFSDS, and reducing the number and size of overflows will fulfil the following 3 Main 1-2 SWMP goals: 1) Remove Sources of Pollution that Threaten Public Health; 2) Restore/Maintain Aesthetically Appealing Conditions 3) Preserve and Enhance the Quality of the Great Lakes 6. Project Evaluation / I&I Reduction Results Sanitary sewer systems include both private and public sources of inflow and infiltration which contribute to increased flow in the system during wet weather events. Private sources include sanitary sewer laterals, and footing drains, which comprise a large portion of the system, and are generally difficult for the City to control because lie within private property. Both infiltration (low rate, high volume), and Inflow (high rate, low volume) sources, can contribute to sanitary sewer system overload during wet weather and thereby contribute to sanitary sewer overflows. Removal of these sources is cost effective due to the high cost for Southfield to transport and treat this volume of additional flow during wet weather, and environmentally beneficial due the reduced potential for SSO s in the system. However, due to limited funds, investigations need to be targeted to identify those sources which can be most easily identified and removed. By targeting areas which were identified as having high peak flow rates, and using manhole inspections and smoke testing as diagnostic tools, data on a large portion of the sanitary sewer system was collected without delay. Table 2 summarizes the projected peak rate removal rates by Sewer District and Sewer Component that resulted from the rehabilitation recommendations of this study. Manhole Rehabilitation provided the greatest estimated peak rate reduction. Most manholes were precast concrete with brick adjusting rings and bolt down covers with the bolts missing. Top portion of manholes are subject to freeze thaw action and when present in low lying areas are subject to inflow from surface water during wet weather. In greenbelt areas where missing bolts in manhole lids allowed surface water to enter the structure, the manhole covers were replaced with solid gasketed covers for ease of future maintenance. Areas 3110, and 3200 show the largest estimated reduction in peak rate per sewer district area. Area 3110 was previously combined and had rear yard sewers with low lying manholes and sewers in poor condition. The sewers are currently being CIPP lined by the City, and the manhole covers with missing bolts are scheduled to be replaced with solid cover gasket sealed lids. Footing drain Page 10

11 removal and manhole rehabilitation in Area 3200 accounts for the projected flow reductions in this district. Table 2 Estimated I/I Removal Rates from Recommended Rehabilitation Activities Sewer District Total # of I/I Removal I/I Removal Source C B Rate (gpm) Sources Manhole Rehab Estimated I/I Removal , (gpm) Footing Drain Removal Estimated I/I Removal (gpm) Private Illicit Connections Estimated I/I Removal (gpm) Sewer Lining and Grouting Estimated I/I Removal (gpm) l.f. CIPP (3110) l.f CIPP (3010) 7 spot (3010) 4 spot (B) 3 spot ( C ) I/I Defect Source Location Inspected Manholes Bid for Rehabilitation City of Southfield Repairs 6-inch Footing Drain line to Guy St. PumpStation. Estimate 60 private FD connections down Somerset & 5gpm/home removed from sanitary sewer via cross connection at MH7093) Smoke Testing (Enforcement - Homeowners and Businesses to remove) Approx 5000 l.f. being completed by Southfield in Adding potential 1000 l.f of lining and grouting joints in area 3010, B, and C Potential I/I Removed (gpm) 104 1, ,114 Parcel Area (ac) # of MH Struct Inspected ,208 # of MH Struct. Could not MH Do not exist or Field Locate are buried Pipe Length (l.f.) 5,734 53,216 10,390 10,656 28,351 66,915 62,147 51,334 27,174 16, ,248 Total Pipelength Avg CCTV and Cleaning Estimated footage Cost per LF under to be completed $13.8 $1.8 $1.8 $1.5 $1.9 $2.2 $ ,619 Oakland County EPA under EPA Grant Grant with Oakland Co. $490, ,629 Recommended Future CCTV and Cleaning l.f. Note: Estimated I/I removal rates are based upon a direct summation of individual source peak I/I rates at identified defect locations in the system. Page 11