Wauwatosa Lateral Rehabilitation Pilot Project. Prepared for City of Wauwatosa Wauwatosa, WI January 18, 2013

Transcription

1 Wauwatosa Lateral Rehabilitation Pilot Project Prepared for City of Wauwatosa Wauwatosa, WI January 18, 2013

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3 Wauwatosa Lateral Rehabilitation Pilot Project Prepared for City of Wauwatosa, Wauwatosa, WI January 18, 2013 Job: Milwaukee Metropolitan Sewerage District Private Property Infiltration and Inflow Reduction Program Wauwatosa Technical Assistance 250 East Wisconsin Ave, Suite 1525 Milwaukee, Wisconsin 53202

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5 Table of Contents List of Figures... v List of Tables... vi List of Abbreviations... vii Executive Summary... ES-1 1. Background and Objectives Background Sources of I/I Objectives Focus Areas Implementation Approach Summary of Work Completed N. 65 th St Eagle St Investigation Rainfall Simulation Soaker Hose Testing Soaker Hose and Dye Water Testing Flow Monitoring Direct observation V-notch Weir Sanitary Sewer Flow Estimation Downstream metering at FM6 on North Avenue Passive Monitoring Evaluation and Results N. 65 th St. Results Soaker Hose Testing Soaker Hose and Dye Water Testing Flow Monitoring Eagle St. Results Soaker Hose Testing Soaker Hose and Dye Water Testing Flow Monitoring Conclusions Pilot Project Flow Reduction Effectiveness Summary of Results by Objective Application of Results to Metershed iii

6 Table of Contents Wauwatosa Lateral Rehabilitation Pilot Project 5.4 Construction Costs Lessons Learned Construction Testing References... REF-1 Appendix A: Lateral Flow Rates... A iv

7 Wauwatosa Lateral Rehabilitation Pilot Project Table of Contents List of Figures Figure ES-1. I/I Effectiveness Evaluation Approach.... ES-3 Figure ES-2. Cumulative Lateral Flows, N 65 th St., Soaker Hose and Dye Water Test... ES-4 Figure ES-3. Cumulative Lateral Flows, Eagle St., Soaker Hose and Dye Water Test... ES-4 Figure ES-4. Comparison of MMSD Performance Standard to Pre- and Post-Rehabilitation Flows... ES-5 Figure 1-1. Project Location Figure 1-2. Public and Private Sources of I/I Figure Dye Water Testing Results: N. 65 th St. Project Area Figure Dye Water Testing Results: Eagle St. Project Area Figure 2-1. I/I Effectiveness Evaluation Approach Figure 2-2. Project Implementation Sequence: N. 65 th St Figure 2-3. Project Implementation - Eagle St Figure 3-1. Soaker Hose Test Schematic Figure 3-2. Soaker Hose and Dye Water Test Schematic Figure 3-3. Lateral Flow Entering Sanitary Sewer Main During Dye Water Testing, N. 65 th St., Round Figure 4-1. Cumulative Lateral Flows, N 65 th St., Soaker Hose Test Figure 4-2. Example of Lateral Flow Rate Reduction from Rounds 0 to 3 of Testing Figure 4-3. Cumulative Lateral Flows, N 65 th St., Soaker Hose and Dye Water Test Figure 4-4. V-notch Weir Flow Measurement, Round 1 Testing on the 2400 Block of N. 65 th St Figure 4-5. Cumulative Lateral Flows, Eagle St., Soaker Hose Test Figure 4-6. Cumulative Lateral Flows, Eagle St., Soaker Hose and Dye Water Test Figure 4-7. V-notch Weir Flow Measurement, Round A Testing on the 7800 to 7900 Block of Eagle St.4-11 Figure 5-1. Conceptual I/I components of a rehabilitated system Figure 5-2. MMSD Performance Standard Figure 5-3. Estimated Pre and Post Rehabilitation Components of Flow Figure 5-4. Pre-rehabilitation Metershed Average I/I Components Figure 5-5. Post-rehabilitation Metershed Average I/I Components (Estimated) Figure 5-6. Comparison of MMSD Performance Standard to Pre- and Post-Rehabilitation Flows v

8 Table of Contents Wauwatosa Lateral Rehabilitation Pilot Project List of Tables Table 2-1. Sequencing of Wauwatosa Lateral Rehabilitation Project Table 5-1. N. 65 th St. Average Lateral I/I Rate (gpm) by Phase Table 5-2. Eagle St. Average Lateral I/I Rate (gpm) by Phase vi

9 Wauwatosa Lateral Rehabilitation Pilot Project Table of Contents List of Abbreviations A-V CCTV cfs CIPP gpad gpm I/I MMSD PPIIR PVC ROW VCP Area-Velocity Closed Circuit Television cubic feet per second Cured-in-Place Pipe gallons per acre per day gallons per minute Infiltration and Inflow Milwaukee Metropolitan Sewerage District Private Property Infiltration and Inflow Reduction Polyvinyl Chloride (pipe material) Right-of-way Vitreous Clay Pipe vii

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11 Executive Summary The City of Wauwatosa implemented a pilot project to determine the effectiveness of different lateral rehabilitation strategies to reduce the contribution of infiltration and inflow (I/I) from laterals. Specifically, the pilot project was undertaken to answer the following questions: 1. How effective is it to rehabilitate the leakiest laterals, rather than all of the laterals in a given focus area? 2. Can significant I/I reduction be achieved by rehabilitating only the portion of a lateral in the public right-of-way (ROW), rather than the entire lateral up to the house? 3. What amount of residual I/I will remain after lateral rehabilitation if foundation drains remain connected to the sanitary sewer system? These questions will help Wauwatosa to identify the best strategy for addressing I/I on private property and for utilizing funding assistance from MMSD for private property I/I reduction. The pilot project was conducted in two focus areas: N. 65 th St. between North Ave. and Clarke St., and Eagle St. between Wauwatosa Ave. and N. 80 th St. These areas were selected based on the results of the report Investigation and Analysis of Sanitary Sewersheds WA4001, WA4002, WA4035 [1], which indicated that these focus areas have some of the highest I/I rates in Wauwatosa. Rehabilitation was conducted in different phases for each of the focus areas. As seen in Figure ES-1, testing followed each rehabilitation phase to identify the effectiveness of each phase for reducing I/I. Testing consisted of flow monitoring and rainfall simulation. The rainfall simulation consisted of applying water to the ground surface over the lateral for each property for a period of two to eight hours using soaker hoses to simulate the effects of rainfall, as well as flooding the storm sewer with water that was dyed green. Figures ES-2 and ES-3, respectively, show the effectiveness of each phase of rehabilitation for N. 65 th St. and for Eagle St. for reducing I/I. After all of the phases of rehabilitation, the contribution of I/I from laterals was reduced by 75% from pre-rehabilitation conditions. I/I from the laterals was reduced from an average of 3 or 4 gpm per property to a residual amount of about 1 gpm per property. The results of the pilot project are site-specific and represent the 118 homes that were included in the pilot project; however, Wauwatosa conducted this pilot project in an attempt to identify a City-wide strategy for addressing I/I. As a result, the findings of the pilot project were put in perspective of the larger metershed area, which includes approximately 3200 homes in Wauwatosa. Flows were estimated for the metershed for pre-rehabilitation conditions as well as if all of the laterals and all of the public sanitary sewer mains and manholes in the entire metershed were rehabilitated (as in the pilot project). This estimate assumes that foundations drains remain connected to the sanitary system. Figure ES-4 shows the changes in flows, on a metershed basis, from the pre- to post-rehabilitation condition relative to the MMSD performance standard for peak flow. As seen in this figure, the rehabilitation provided a reduction in flows but additional reduction is needed to bring the flows down to what is required for the MMSD performance standard. The remaining flows consist of residual I/I from the laterals, the sanitary sewer mains, and the sanitary sewer manholes, as well as I/I from the foundation drains that are on most properties that were built before Foundation drains are a major contributor of I/I. ES-1

12 Executive Summary Wauwatosa Lateral Rehabilitation Pilot Project Answers to the pilot project objectives are as follows: 1. How effective is it to rehabilitate the leakiest laterals, rather than all of the laterals in a given focus area? Targeting the leakiest laterals provided an incremental reduction in I/I, but all laterals needed to be lined to achieve the greatest degree of reduction possible. 2. Can significant I/I reduction be achieved by rehabilitating only the portion of a lateral in the public ROW, rather than the entire lateral up to the house? Rehabilitating the lower section of all laterals in the public ROW appears to be effective at reducing the majority of the I/I from the laterals. Subsequent rehabilitation by extending the lining to the upper sections of laterals did not significantly reduce the average I/I into the laterals beyond approximately 1 gpm. This may be because the lateral lining in the ROW rehabilitates the lateral where it crosses under the storm sewer. 3. What amount of residual I/I will remain after lateral rehabilitation if foundation drains remain connected to the sanitary sewer system? Neither of the pilot projects evaluated the contribution of foundation drains to the total I/I. Therefore the significance of the remaining I/I from foundation drains is unknown; however, an analysis of flow monitoring data and other sources of information suggest that the I/I contribution from foundation drains is in the range of 2 to 3 gpm. If the average residual lateral I/I rates after rehabilitation are approximately 1 gpm, then the sum of private property sources (laterals and foundation drains) is approximately 3 to 4 gpm. Aside from the replacement of the sanitary sewer main and lateral connections on N. 65 th St., which occurred in 2011, the rest of the rehabilitation work was completed from May through October Excluding testing, the cost for a 60-foot long lateral lining ranged from $5,300 to $7,100, depending on the approach implemented. It is anticipated that the costs for future work will be less because the work will not be completed in increments. Future costs are estimated to be $4,700 to line the lateral just to the property line and $6,000 to line the lateral to the house. ES-2

13 Wauwatosa Lateral Rehabilitation Pilot Project Executive Summary North 65 th Street Eagle Street Initial Testing Initial Testing Public ROW Sewer Replacement + 4 lateral replacement Public ROW Sewer Main Lining + All Laterals Lined to Sidewalk Testing Testing Private Property Targeted Laterals Lined (from 4 replacement to house) Private Property Targeted Laterals Lined (from sidewalk to house) Testing Testing Private Property Remaining Laterals Lined (from 4 replacement to house) Private Property Remaining Laterals Lined (from sidewalk to house) Testing Testing Figure ES-1. I/I Effectiveness Evaluation Approach. ES-3

14 Executive Summary Wauwatosa Lateral Rehabilitation Pilot Project Cumulative Lateral Flow Rates (gallons per minute) Cumulative Lateral Flow Rates Soaker Hose and Dye Water Test Round 0 = pre rehabilitation Round 1 = new PVC main and lateral stubs Round 2 = targeted lateral liners from stubs to cleanouts Round 3 = remaining lateral liners Round 0 Round 1 Round 2 Round 3 Round 0 dye test revised Round 1 Round 2 Round 3 0 Clarke St MH 332 MH 499 MH 327 MH 325 MH 322 MH 320 MH 318 Wright St Addresses on N 65th St Figure ES-2. Cumulative Lateral Flows, N 65 th St., Soaker Hose and Dye Water Test Meinecke North Ave Round 0 Round A Round B Round C Cumulative Lateral Flow Rates Soaker Hose and Dye Water Test Cumulative Lateral Flow Rates (gallons per minute) Round 0 = Pre rehabilitation Round A = all laterals in lined in ROW and sanitary main lined Round B = targeted lateral liners from sidewalk to cleanouts Round C = remaining lateral liners from sidewalk to cleanouts No stormwater pipe in front of these properties Not tested in Round 0 Round 0 dye test revised Round A Round C Round B 0 N 80th St MH218 MH217 MH216 N 78th St MH214 Addresses on Eagle St, Wauwatosa MH212 MH211 MH210 Wauwatosa Ave Figure ES-3. Cumulative Lateral Flows, Eagle St., Soaker Hose and Dye Water Test ES-4

15 Wauwatosa Lateral Rehabilitation Pilot Project Executive Summary 7 Typical Flow per Property (gpm per property) MS0411 measured total 5.4 gpm Approx 4 gpm 5 year Recurrence Interval Peak Hourly Flow 2.8 gpm 1 0 Pre Rehab Estimated Post Rehab MMSD Perf Std Figure ES-4. Comparison of MMSD Performance Standard to Pre- and Post-Rehabilitation Flows ES-5

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17 Section 1 Background and Objectives 1.1 Background In 2011, the City of Wauwatosa (Wauwatosa) conducted a study to identify system improvements to reduce basement backups in three sewersheds on the east side of Wauwatosa (Investigation and Analysis of Sanitary Sewersheds WA4001, WA4002, WA4035 [1]). These sewersheds, which are indicated in Figure 1-1, were identified by the Milwaukee Metropolitan Sewerage District (MMSD) as having excessive wet weather peak flows. The study included flow monitoring, hydraulic modeling, evaluation of condition assessment data, evaluation of infiltration and inflow (I/I) reduction, and the development of a sewer system improvement plan. A major conclusion of the study was that private sanitary sewer laterals and foundation drains connected to the sanitary laterals contribute a substantial portion of I/I in these basins. As a result, Wauwatosa elected to perform a pilot project to determine the effectiveness of different lateral rehabilitation strategies for reducing I/I. Wauwatosa received funding assistance from MMSD s Private Property Infiltration/Inflow Reduction (PPIIR) program to assist with the development, design, public involvement, investigations, and implementation of private property rehabilitation for this pilot program. 1-1

18 Section 1 Wauwatosa Lateral Rehabilitation Pilot Project Figure 1-1. Project Location 1-2

19 Wauwatosa Lateral Rehabilitation Pilot Project Section Sources of I/I Infiltration and Inflow (I/I) is flow that enters the sanitary sewer system that should not be there (e.g. groundwater infiltration, stormwater runoff). For the metershed as a whole, I/I that enters the sanitary sewer system is the cause of excessive flows. The sanitary sewer mains and manholes are public sources of I/I. Laterals, foundation drains, and direct inflow from roof drains if incorrectly connected to the sanitary system are private sources of I/I. (The pilot project areas did not have any connected roof drains.) Figure 1-2 shows the various sources of I/I that may be found on a single residential property and from a single sanitary sewer and manhole to which the residential property is tributary. (The sanitary sewage component of the flows is a small portion of the total flows and therefore the total flows are nearly entirely I/I.) Estimated I/I rates are given in terms of gallons per minute (gpm) for both public and private sources and are meant to show the relative contribution of each source to the overall total I/I of a large metershed area. Individual components for any one property may vary greatly. The I/I values were obtained by dividing the total flow of the metershed by the number of properties in the metershed so that the I/I can be expressed as gpm per property, even for the public sources of I/I. In Figure 1-2, the I/I is 5.4 gpm per property, which corresponds to a 5-year recurrence interval flow for metershed MS0411 averaged over all of the properties in the metershed. Foundation drains may be the single largest source of I/I, contributing almost half of the total I/I. Lateral I/I may be another large source of I/I, contributing perhaps a third of the total. Public sources of I/I may account for approximately 20% of the total. The percentages in the figure should be taken as conceptual estimates to help understand the general nature of the problem, rather than a fixed rule. Figure 1-2. Public and Private Sources of I/I 1-3

20 Section 1 Wauwatosa Lateral Rehabilitation Pilot Project 1.3 Objectives The focus of the pilot project was on the rehabilitation of laterals to reduce I/I. Foundation drains remained connected to the laterals. Therefore, one of the key objectives of this investigation was to determine how much I/I reduction could be achieved by lateral rehabilitation while the foundation drains remain connected. Other objectives of this study were related to the degree of lateral rehabilitation. Extensive dye water testing was conducted in the study area in 2010 and 2011 and this testing indicated that approximately one third of the laterals are the source of most of the leakage. In the dye water test, a number of properties showed no leakage and others had relatively small rates of leakage. Therefore, one of the objectives of this study was to investigate whether rehabilitation of targeted laterals with the highest I/I rates could achieve a significant overall reduction in leakage or if all laterals must be rehabilitated to avoid migration of clear water to the remaining, un-rehabilitated laterals. Another objective of this study was to investigate whether rehabilitation of the lateral in the public rightof-way (ROW) could achieve a significant reduction in leakage. The evaluation of this objective compared the leakage reduction for liners installed in the lower sections of laterals in the public ROW (from the sanitary sewer main to the sidewalk) to liners installed in the full length of the laterals (from the sanitary sewer main to the house). In summary, Wauwatosa used the pilot project to determine the effectiveness of different rehabilitation strategies to answer the following questions: 1. How effective is it to rehabilitate the leakiest laterals, rather than all of the laterals in a given focus area? 2. Can significant I/I reduction be achieved by rehabilitating only the portion of a lateral in the public ROW, rather than the entire lateral up to the house? 3. What amount of residual I/I will remain after lateral rehabilitation if foundation drains remain connected to the sanitary sewer system? 1.4 Focus Areas Two focus areas were included in the pilot project: N. 65 th St. and Eagle St. Three blocks on N. 65 th St. were selected as a focus area because, as seen in Figure 1-3, the dye water testing that was conducted in 2010 indicated that this area had high leakage rates and a storm sewer. In addition, Wauwatosa replaced the public sanitary sewer main and the connections of the laterals to the sanitary sewer main during the summer of The lateral connections were replaced with approximately 4 feet of polyvinyl chloride (PVC) pipe. Because of this recent work on the public system, the pilot project could begin immediately since all possible work had already been completed on the public system. In addition, because the first four feet of the laterals had been replaced, the first phase could evaluate the change in leakage response due to this recent work. Two blocks on Eagle Street were selected as a focus area because the dye water testing that occurred in 2011 indicated high leakage rates, the street had a storm sewer, and its sanitary sewer main was recommended for lining in the 2011 Sewer System Improvement Plan. Both project sites are near the upstream end of their respective collection system service areas. As a result, monitoring flow in the sanitary sewer mains immediately downstream of the project area would result in a relatively direct measure of the flow condition changes resulting from the project. 1-4

21 Wauwatosa Lateral Rehabilitation Pilot Project Section 1 Figure Dye Water Testing Results: N. 65 th St. Project Area 1-5

22 Section 1 Wauwatosa Lateral Rehabilitation Pilot Project Figure Dye Water Testing Results: Eagle St. Project Area 1-6

23 Section 2 Implementation 2.1 Approach The approach for implementing the pilot project was to first rehabilitate the sanitary sewer main and a portion of the lateral that was within the public ROW. Next, a targeted sub-group of private laterals was rehabilitated. This targeted sub-group (also referred to as the Priority 1 laterals) was selected based on observed leakage rate estimates from the dye water testing that was performed in 2010 in the N. 65 th St. focus area and in 2011 in the Eagle St. focus area. Those laterals that had an estimated leakage rate of 5 gallons per minute (gpm) or more were placed into the targeted laterals category. The last step was to rehabilitate the remaining laterals (Priority 2 laterals) within the focus areas. Each phase of rehabilitation was followed by testing, which included dye water testing and soaker hose testing. Figure 2-1 shows the overall sequencing of the project. North 65 th Street Eagle Street Initial Testing Initial Testing Public ROW Sewer Replacement + 4 lateral replacement Public ROW Sewer Main Lining + All Laterals Lined to Sidewalk Testing Testing Private Property Targeted Laterals Lined (from 4 replacement to house) Private Property Targeted Laterals Lined (from sidewalk to house) Testing Testing Private Property Remaining Laterals Lined (from 4 replacement to house) Private Property Remaining Laterals Lined (from sidewalk to house) Testing Testing Figure 2-1. I/I Effectiveness Evaluation Approach. 2-1

24 Section 2 Wauwatosa Lateral Rehabilitation Pilot Project 2.2 Summary of Work Completed Table 2-1 provides a summary of the construction and testing that was completed and the dates that it was completed. The lateral rehabilitation work for N. 65 th St. and Eagle St., which was covered under Wauwatosa Contract 12-99, occurred from June 2012 through October Laterals were lined with cured-in-place-pipe (CIPP) liners, with hydrophilic seals at each end of the liner to reduce leakage. Cleanouts were also installed under Contract All cleanouts were installed using VAC-A-TEE by LMK Enterprises. For this system, a 1- to 2-foot hole was hydro-excavated above the lateral for the cleanout. Next, a PVC connector (saddle) and riser pipe was bonded to the lateral. Finally a hole was cut into the lateral to establish a cleanout access point. The location of the cleanout was to be as close to the house as possible but in many cases the lateral could not be located because: 1. The lateral could not be televised fully because of roots, deposits, configuration, or conditions; 2. Landscaping and/or the placement of porches, sidewalks and driveways prevented a cleanout close to the house; 3. The homeowner requested a cleanout in a different location. Staff from Wauwatosa, BC, MMSD, and the contractor (Musson Bros.) reviewed and agreed upon the locations of the cleanouts prior to their installation. All but one of the homeowners within the Eagle St. focus area and all but five homeowners within the N. 65 th St. focus area (including one with a targeted lateral) agreed to participate in the program. In addition, one lateral for N. 65 th St. and one lateral for Eagle St. were not rehabilitated. The lateral at 2374 N. 65 th St. was replaced by the homeowner about three years ago and was not lined under Contract since it was deemed to be in good condition. The lateral for 7715 Eagle St. was not lined because a dye water test, performed by the City of Wauwatosa, confirmed that this lateral connects to the lateral from 7717 Eagle St., which then connects to the sanitary sewer main. The exact location of this connection is unknown and as a result, 7715 Eagle St. was not lined under Contract Table 2-1. Sequencing of Wauwatosa Lateral Rehabilitation Project Phase Focus Area N. 65th St. Eagle St. Total Number of Laterals in Focus Area Total Number of Laterals Rehabilitated Pre-Rehabilitation Testing Round 0: August/September 2010 Round 0: April 2011 Type of Sanitary Sewer Main and Manhole Rehabilitation Replacement CIPP Lining Dates of Sanitary Sewer Main Rehabilitation June 2010 May 2012 Type of Lateral Rehabilitation within ROW Replace first 1 to 4 feet with PVC CIPP Lining of first approx. 30 feet (to public ROW line) Dates of ROW Lateral Rehabilitation June 2010 July 23 to Aug. 2, 2012 Dates of Cleanout Installation June 25 to Aug.18, 2012 June 15 to July 13, 2012 Public Property Rehabilitation Effectiveness Testing Round 1: June 25-27, 2012 Round A: Aug. 8-9, 2012 Number of Targeted (Priority 1) Laterals Rehabilitated

25 Wauwatosa Lateral Rehabilitation Pilot Project Section 2 Table 2-1. Sequencing of Wauwatosa Lateral Rehabilitation Project Phase Focus Area N. 65th St. Eagle St. Percentage of Targeted Laterals out of Total Number of Focus Area Laterals 32% 43% Type of Targeted Laterals Rehabilitation CIPP Lining from PVC connection stub to house (approx.) CIPP Lining from ROW to house (approx) Dates of Targeted Laterals Rehabilitation Aug. 20 to Sept. 5, 2012 Aug. 9 to Aug. 31, 2012 Targeted Laterals Rehabilitation Effectiveness Testing Round 2: Sept. 6-10, 2012 Round B: Sept. 4-5, 2012 Number of Remaining (Priority 2) Laterals Rehabilitated Percentage of Remaining Laterals out of Total Number of Focus Area Laterals 61% 52% Type of Remaining (Priority 2) Laterals Rehabilitation CIPP Lining from PVC connection to house (approx) CIPP Lining from ROW to house (approx) Dates of Remaining Laterals Rehabilitation Sept. 11 to Oct. 12, 2012 Sept. 6 to Sept.27, Remaining Laterals Rehabilitation Effectiveness Testing Round 3: Oct , 2012 Round C: Sept , One property (7835 Eagle St.) was lined after the last round of soaker hose and dye water testing for that focus area. The lateral for this property had another pipe connected to the lateral and it took additional time to investigate whether this pipe was active and to work with the homeowner to decide on an appropriate lining approach. Ultimately the homeowner decided to have the lateral lined completely through, therefore closing off the connection of the second pipe to the lateral N. 65 th St. Figure 2-2 provides a visual of the work and testing that was completed for N. 65 th St. and the order in which it was completed. The process was as follows: In 2011, the old clay sanitary sewer main was replaced with a new PVC pipe. Connections of the laterals to the sanitary sewer main were also replaced with PVC. The new lateral connections were generally about 4-feet long; however, some of the PVC pipes were only 1- to 2-feet long. The segments of new lateral were not sufficiently long to cross under the storm sewer. New manholes were also constructed at this time. All of the rehabilitation was within the public ROW and work was completed on all of the laterals within the N. 65 th St. focus area. Round 1 of soaker hose and dye water testing was conducted in June 2012 to test the effectiveness of rehabilitating public property infrastructure for reducing I/I. Following Round 1 testing, targeted laterals were CIPP-lined from the PVC lateral connection pipe to the cleanout or house, depending on the cleanout s location. Hydrophilic seals were installed at both the upstream and downstream ends of the liner to reduce the chance of leakage at these connections. Round 2 of soaker hose and dye water testing occurred in late September 2012 and observed the effectiveness of rehabilitating the targeted laterals. Following Round 2 testing, the remaining laterals within the focus area were CIPP-lined from the PVC lateral connection pipe to the cleanout or house. Round 3 of soaker hose and dye water testing occurred in mid-october 2012 and observed the effectiveness of rehabilitating all of the remaining laterals within the N. 65 th St. focus area that were included in the program. In most cases where the cleanout was not sufficiently close to the house (as determined by Wauwatosa, BC, and MMSD staff), the contractor installed the liner from the sanitary sewer main to the house, lining 2-3

26 Section 2 Wauwatosa Lateral Rehabilitation Pilot Project through the cleanout. Lining from the sewer main was not anticipated for N. 65 th St. so the contractor used a brim connection liner to stabilize the liner at the sanitary sewer main and to keep the pressures down during liner installation. Laterals with cleanouts sufficiently close to the house were lined from the cleanouts to the sanitary sewer main. All lined laterals had hydrophilic seals installed at each end of the lateral liners, to help prevent leaking at the connection points between the existing laterals and the new liners. The PVC lateral connection for the sanitary sewer main was shorter than anticipated in some cases. This, combined with numerous bends in the lateral connection pipes, contributed to the following laterals having liners that were short of the PVC lateral connection pipe and therefore not meeting specifications: 2329 N. 65th (missed PVC overlap by 6-inches) 2434 N. 65 th (missed PVC overlap by 6-inches) 2446 N. 65th (missed PVC overlap by 1-inch) 2503/2505 N. 65 th (missed PVC overlap by 6-inches) 2523 N. 65 th (missed PVC overlap by 6-inches) BC reviewed videos of these laterals from when they were televised during the last round of soaker hose and dye water testing, to determine whether the laterals were leaking. There appeared to be no issues with 2446, 2503/2505, and 2523 N. 65 th St., but the review of 2329 and 2434 N. 65 th St. was inconclusive. Wauwatosa plans to have all five of the laterals with short liners air pressure tested; if the lateral fails the air pressure test, then the first five feet of the lateral and the lateral connection to the sanitary sewer main will be grouted. Figure 2-2. Project Implementation Sequence: N. 65 th St. Note: cleanout locations varied by property. 2-4