INDIANAPOLIS DEPARTMENT OF CAPITAL ASSET MANAGEMENT COMBINED SEWER INFRASTRUCTURE ASSESSMENT. Final Report. Greeley and Hansen.

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1 INDIANAPOLIS DEPARTMENT OF CAPITAL ASSET MANAGEMENT COMBINED SEWER INFRASTRUCTURE ASSESSMENT Final Report Greeley and Hansen June 1996 A. Introduction The collapse of old sewers can result, and in other cities has resulted, in loss of life and expensive street and sewer repairs. The goal of the Combined Sewer Infrastructure Assessment Project is to identify, inspect, and provide a priority list for the rehabilitation of vulnerable sewer segments to reduce the potential for incidences of failure. The project was divided into two phases. The report covering the first phase, Combined Sewer Infrastructure Assessment Phase I Report, October 1995 included: A review of data on approximately 360,000 feet of combined sewers 60-inch diameter and larger. Spreadsheets that show the characteristics and condition of each sewer segment 60- inch diameter and larger. Base maps that show the location of sewer segments 60-inch diameter and larger. Sewer segments rating based on consequences of failure. Walk-through inspection of 59,490 feet of high priority sewers. A review of inspection results and assigning rehabilitation priority ratings based on sewer condition. Early action rehabilitation projects. Updating the City s data base. The report covering the inspection portion of the second phase, Combined Sewer Infrastructure Assessment Inspection and Assessment Report, February 1996 included: Additional inspection of 197,122 feet of critical sewers. 1

2 A review of inspection results and assigning rehabilitation rating based on sewer condition. A structural performance assessment of the combined sewers. The development of sewer rehabilitation projects including early action rehabilitation projects. Update the City s database. The project team for the Combined Sewer Infrastructure Assessment included the City of Indianapolis, Greeley and Hansen, WRc, Specialty Sewer Services and VS Engineering. The City of Indianapolis provided overall guidance on the project and furnished sewer information. Greeley and Hansen was the project manager, provided technical expertise, managed data, assessed the structural condition of the sewers, recommended a priority list of sewers to be rehabilitated, prepared opinions of probable construction costs and developed a sewer inspection program. WRc provided a ranking of critical sewers based on each sewer s consequence of failure. Specialty Sewer Services performed the walk-through and pan-and-tilt TV inspections. VS Engineering assisted Specialty Sewer Services during the inspections by providing traffic control and assisting in confined space entry. This report presents the findings of Phase I, the Inspection and Assessment of critical sewers, evaluation of rehabilitation alternatives, preparation of opinions of probable construction costs, prioritization of sewer rehabilitation projects and the development of an inspection program. B. Phase I Background Information Presented in Appendix A are spreadsheets showing the characteristics and condition of the combined sewer segments for all sewers 60" in diameter and larger. The following information was gathered and reviewed in the preparation of these spreadsheets: Management Information System data (Wastewater Collection Management System or WCMS) for the 19 combined sewer basins on computer disks. Indianapolis Mapping and Geographic Information System (IMAGIS) maps, hard copies and on computer disks. 2

3 Two-foot contour maps of the sewer system. Interceptor maps. Sewer record drawings (reviewed at City-County Building). Aerial photographs. Manhole inspection reports. Marion County geological and hydrogeologic surveys. Primary and secondary road map from Indianapolis Department of Capital Asset Management (DCAM) Traffic Division. Traffic counts from DCAM Traffic Division. Chamber of Commerce Infrastructure Task Force Report for critical sewer locations. Maintenance history from Department of Public Works (DPW) Sewer Maintenance and Construction Engineering. C. Characteristics and Condition of Sewer Segments WCMS data for the 19 combined sewer basins were delivered to Greeley and Hansen on computer disks on January 25, The data were organized into initial spreadsheets containing a sewer map number, upstream and downstream manhole numbers, street address of upstream manhole, sewer width or diameter, sewer height, sewer shape, type of sewer material, sewer length and surface cover. Approximately one-third of this information was not in the WCMS data and had to be obtained from other sources including record drawings, manhole inspection reports, two-foot contour sewer maps and site visits. The spreadsheets were then expanded to include the following information: Record drawing numbers, the year built, feet of cover at the upstream manhole from record drawings. Soils type along the sewer and depth of water table from geological and hydrogeological surveys. 3

4 Unique surface features from aerial photographs and maps. Amount of traffic flow and importance of the street above the sewer from information provided by DCAM s Traffic Division. Sewer maintenance history, sewer condition and rehabilitation history, from Maintenance Supervisors at DPW. The data were then sorted into manageable and logical groups from an upstream manhole to the furthest downstream manhole of a basin. D. Base Maps Figure 1 is an index map that was developed from the IMAGIS DXF files and shows all combined sewers 60 inches and larger. Figure 2 (5 sheets) shows the combined sewers 60-inch diameter and larger on street maps. The index map, Figure 1, cross-references Figure 2 and the characteristics and condition spreadsheets in Appendix A. Sewer runs were labeled to reference the sheet numbers of Figure 2, basin number and street name at the upstream manhole. Figure 2 was developed from IMAGIS DXF files for the 19 combined sewer basins. Missing sewers were added and sewer routes were corrected. Major streets, major waterways and significant structures were labeled. E. Consequence of Failure Rating Greeley and Hansen contracted with WRc to develop a priority rating for each sewer segment in Appendix A based on its consequence of failure. WRc used a diagnostic approach of rating sewers based on the criterion that if a sewer should fail, then the subsequent costs to rehabilitate it would be significantly higher than if the sewer were rehabilitated before failure. The data on the infrastructure in Appendix A were examined by WRc and each sewer segment was assigned a consequence of failure rating, also called Overall Cost Factor (OCF). Each sewer segment received an OCF score ranging from 1.0 to 1,000.0 with the highest score deemed the most critical. For example, sewers under high traffic volume intersections, under railroad tracks, and under buildings were given high overall cost factors. The OCF for each segment was entered in the first column of the spreadsheets in Appendix A. 4

5 Because it is more cost-effective to inspect entire sewer runs than to inspect individual sewer segments, priority ratings of entire sewer runs of a logical extent from upstream to downstream were developed. Some of the sewer runs had segments that had been rehabilitated between 1986 and The OCF scores and lengths of these recently rehabilitated segments were deleted from consideration in rating the sewer runs for walk-through inspections because they had received adequate inspection during the rehabilitation projects. Each remaining individual segment s OCF was multiplied by its length. These numbers for each sewer run were totaled and are listed in Table 1 as Total OCF x Length. The sewer run s Total OCF x Length was then divided by the total length of the sewer run excluding segments rehabilitated between 1986 and This gives the sewer run a weighted average of the OCF. Table 1 shows sewer runs in the order of priority based on the weighted average OCF s. The first five sewer runs listed in Table 1 were identified by the City and Greeley and Hansen as high priority for walk-through inspection. Table 1 shows other critical sewer runs identified for walk-through inspection in Phase I (Footnote (4)). WRc s report summarizing the findings of the critical sewer categorization study was submitted to the City on August 30, F. Preliminary Screening Preliminary screening was performed on the most critical sewer runs, all sewer runs through Sewer Run th B on Table 1. Total sewer length for these sewer runs was 164,293 feet (see Table 2). Through review of existing information and meetings with the City, the following sewer lengths were screened from Phase I walk-through inspection (see Table 2): 33,614 feet of sewer were identified as Rehabilitated Between 1986 and 1994 and walk-through inspection was not required. These sewers were screened from walkthrough inspections based upon discussions with DCAM Project Managers and after reviewing DCAM s wall map of shotcrete rehabilitation projects. 27,550 feet of sewer were identified as having high water depth and were assigned to Pan-and-Tilt Phase II inspections. These sewers were identified to be deleted from walk-through inspections based upon discussions with supervisors of the Sewer Maintenance Division. At DCAM s request, DPW would inspect 4,367 feet of Sewer Runs 4-22-Alabama 5

6 and 2-19-Meridian. Pan-and-tilt inspection is a method of sewer inspection that uses a floating video camera system with a remote controlled lens that has the ability to pan in and out and rotate to view the top and sides of the sewer. G. Street-level Manhole Inspections Street-level manhole inspections were performed by Specialty Sewer Services, Inc. on the critical sewer runs that remained after preliminary screening. Street-level manhole inspections were conducted on 98,762 feet of sewer. By utilizing a supervisor of the sewer technician crew to open manholes and visually inspect the safety conditions for worker entry, the street-level manhole inspections provided a cost-effective means to assess relatively greater lengths of the collection system than using TV camera or worker entry inspection methods. It also provided an efficient method of planning the work by determining the location of set-ups. Certain manholes were discovered to be inaccessible during this process (see Table 3). Through street-level manhole inspections, the following sewer lengths were screened from Phase I walk-through inspections (see Table 2): 33,021 feet of sewer were observed as having high water depth and were assigned to pan-and-tilt inspection under Phase II. 6,251 feet of sewer require heavy cleaning before inspection is possible. The 59,490 feet of sewer remaining after preliminary screening and street-level manhole inspections were identified for walk-through inspections - Phase I. Figure 1, Table 1 and Table 2 show sewer runs identified for walk-through inspections under Phase I. 6

7 H. Combined Sewer Infrastructure Assessment - Phase I 1. Walk-through Inspections Walk-through inspections were conducted in September 1994 of 59,490 feet (see Table 2) of selected sewers 60-inch diameter and larger. The purpose of the walk-through inspections included establishing safety and cleaning requirements, recording obvious structural damage and general structural condition, obtaining additional field data and verifying existing data used for the combined sewer infrastructure assessment. Flow depths were not routinely measured during the assessment. Because flow depths in large combined sewers change from hour to hour and also depend upon rain events, instantaneous flow depth measurements would be of questionable value. Flow depth was used, however, as a criterion for the decision to walk-through or pan-and-tilt TV inspect the sewer. Specialty Sewer Services, Inc., performed the walk-through inspections with the assistance of VS Engineering. Sewer maps, evaluation criteria and inspection forms (Appendix B) were furnished to Specialty Sewer for the inspections. Data collected by Specialty Sewer included: Color VHS video tapes Color 35 mm photographs Inspection forms filled in by the inspector (Appendix B) Internal Inspection Log for Sherman Drive Color photographs, inspection forms and internal inspection log are included in Report of Field Investigations, Phase I Sewer Inspections, October Video tape recording of sewer inspections is contained on four video tapes, submitted to the City under separate cover. Details on the sewer inspection forms are presented in a subsequent section. 2. Phase I Results Inspection data were gathered on the 59,490 feet of sewer. These data were used in the Phase II Assessment discussed in the following section (see Figure 3). Sewer Runs Sherman and 4-21-Adler were identified for early action rehabilitation projects and are summarized in Table 4. Segment of Sewer Run 4-22-McCarty and Segments 7

8 225797, and were identified as unsafe for walk-through inspections due to water levels being too high. 3. Transfer of Data - Phase I After completing and verifying the data in the spreadsheets (Appendix A) during the walk-through inspections, the data were transferred to the City on December 15, 1994, both electronically and by hard copy. Data for the City s Wastewater Collection Management Systems (WCMS) were formatted to meet the City s sewer main inventory system. Because the spreadsheets were completed using a Lotus spreadsheet and the City s WCMS database uses the Hansen software format, data were converted into an ASCII text file. This file replaced and overwrote the corresponding files of the City s database. I. Combined Sewer Infrastructure Assessment - Phase II 1. General Phase II work includes additional inspection of 256,612 feet of critical sewers, structural performance assessment of the sewers, and the development of sewer rehabilitation projects including early action rehabilitation projects. The additional critical sewer inspection included walk-through inspection of sewers not inspected during Phase I and pan-and-tilt TV inspection of sewers with flows too high to be safely inspected by walkthrough. 2. Structural Performance Assessment A structural performance assessment was conducted to rate the need for rehabilitation of each inspected sewer segment and ultimately permit the establishment of a cost-effective and timely rehabilitation program. The assessment combined the findings of the field sewer inspections (Sewer Condition Ratings) with internal and external factors to determine the Overall Structural Grade. These internal and external factors would accelerate sewer deterioration and, therefore, have an impact on the structural performance of the sewer. a. Structural Condition Scores on Sewer Inspection Forms The sewer inspections (walk-through and pan-and-tilt) were reported on inspection forms for each segment. Two walk-through inspection forms were used, 8

9 one for brick and segmented tile sewers and another for concrete sewers. The structural conditions of brick and segmented tile sewers were rated on a score of 0 (no visible signs) to 3 (excessive signs of deterioration) for each of the following: Cracking. Deflection. Missing bricks. Dropped invert. Concrete sewers (both reinforced concrete pipe and cast-in-place) were rated on a 0 to 3 score for each of the following: Cracking. Deflection. Corrosion. Subsidence. The inspection forms also included blanks for additional information such as cleaning required, flow depth, evidence of surcharging and comments. Blank inspection forms are presented in Appendix B. Completed inspection forms are in Specialty Sewer Services, Inc., Report of Field Investigations. b. Sewer Condition Rating The sewer condition rating of each segment was determined from the structural condition scores in the inspection reports utilizing the sewer condition matrix shown in Table 5. The matrix is a logical and systematic set of criteria that compiles the structural condition scores and determines each segment s sewer condition rating. For example, segment number of 4-67-Michigan is a brick sewer that was inspected during Phase I. It received a structural condition score of 2 for cracking, a structural condition score of 2 for deflection, a structural condition score of 1 for missing bricks and a structural condition score of 0 for dropped invert. From the matrix, since there were no structural condition scores of 3, two structural 9

10 condition scores of 2 and one structural condition score of 1, this sewer segment would have a sewer condition rating of 4. The sewer condition rating scores ranged from 1 to 5; a score of 1 is good, 2 is fair, 3 is moderate, 4 is poor and 5 is severe. These sewer condition rating scores are also shown in the final column of Tables 6, 7, and 8. c. Overall Structural Grade As previously noted, sewer condition ratings from walk-through and panand-tilt TV inspections were then combined with the internal and external factors shown in Figure 4 to develop the overall structural grade. The internal factors are evidence of surcharging and evidence of infiltration. Surcharging can weaken the combined sewer, especially at the joints. Continued surcharging of the sewer results in infiltration and exfiltration, which creates paths for the possible influx of soil particles. The loss of soil forms voids outside the sewer walls. This loss of external support may allow the sewer to deflect, which could cause cracks and deformation of the sewer. Observed evidence of surcharging was reported on the inspection forms. Infiltration also may occur in sewers that do not experience surcharging. Evidence of infiltration may be observed at cracks and joints in a pipe and whenever roots penetrate the sewer. Visible signs of infiltration include: Lime deposits. Leaking at joints or cracks. Root intrusion. Mortar loss in brick sewers. Dropped invert. Crown cracking. Reports of observed evidence of infiltration were documented on the inspection forms and were noted during review of videotapes of the walk-through inspections and pan-and-tilt TV inspections. 10

11 The external factors are soil type, the groundwater level and the sewer s depth of cover. These external factors are conditions that adversely affect the structural capacity of a sewer segment. Sewer segments with structural problems can experience accelerated degradation under these conditions. The native soil type surrounding the sewer segment is important in the formation of voids on the outside of sewer walls. Voids are less likely to occur in cohesive soil. Information for soil types along the sewer was gathered using U.S. Geological Survey maps. The water table is a potential source of infiltration. Water table elevations can fluctuate during and after rain events which can affect the soils along the sewer. If the elevation of the water table is higher than the elevation of the invert of the sewer, then infiltration can occur during dry weather periods. Water table elevations were estimated from U.S. Geological Survey maps showing piezometric water surface and hydrogeologic settings. The sewer s depth of cover can also affect the sewer structure. If increased loads are placed on the sewer, then cracks or deflection can occur causing infiltration or structural failure. Sewers deeper than 20 feet are subject to significant dead loads. Shallow sewers are subject to more influence from live and impact loads from trains or vehicles than deep sewers. Shallow sewers may also be subject to building or heavy structure loads. Depth of cover was gathered from reports written from manhole inspections in 1988 and from sewer record drawings reviewed at the Department of Public Works. The sewer condition ratings were combined with the internal and external factors to develop an overall structural grade for each sewer segment inspected. Only sewer condition ratings with a score of 2, 3 or 4 were combined with internal or external factors. If a sewer segment had a sewer condition rating of 1, then the segment was judged to be in such good condition that no near term sewer rehabilitation project would be required. Sewers with sewer condition ratings of 5 were considered in need of attention and, therefore, no adjustment in rating was considered. Figure 5 is the logic diagram for the determination of the overall structural grade. 11

12 J. Sewer Inspection Results Phase I walk-through inspections were conducted in September 1994 and Phase II walkthrough inspections were conducted December 1994 through April The objectives of the walk-through inspections were to assess the general structural condition of the sewers, to record obvious structural distress, to identify early action projects, and to identify cleaning and rehabilitation requirements. Specialty Sewer Services, Inc., performed the walk-through inspections with the assistance of VS Engineering. Two Specialty Sewer Services sewer technicians entered the manhole of the sewer segment to be inspected. The sewer technicians videotaped upstream and downstream of the manhole and recorded any obvious structural distress. They also measured the diameter of the sewer, verified the pipe material and checked the manhole for any evidence of surcharging. Technicians then examined the sewer for cracks and deflection, and corrosion and subsidence in concrete sewers, or missing bricks and dropped invert in brick sewers and entered a structural condition score on the inspection form. They also made recommendations for cleaning and estimated the amount of debris. Flow depth was monitored continuously for the sewer technicians safety. Sewer technicians stopped every 100 feet, or wherever there was an obvious structural problem, and videotaped and photographed the sewer. During the walk-through inspections, VS Engineering performed traffic control and assisted in confined space entry safety procedures. For sewers with high water levels, even during low flow periods, inspections were performed with a pan-and-tilt TV camera. The camera was mounted on a floating skid with a remote-controlled lens that has zoom and 360-degree view capability. The TV camera filmed the entire length of the sewer. A blank pan-and-tilt inspection form is provided in Appendix C. Completed inspection forms are in Specialty Sewer Services, Inc., Report of Field Investigations. Structural condition scores of 0 (no visible signs) to 3 (excessive signs of deterioration) were assigned by a Greeley and Hansen engineer when reviewing the video tapes and the pan-and-tilt inspection forms. Figure 1 is an index map showing the combined sewers 60-inch diameter and larger and the method of inspection. An in-depth inspection was performed on Sewer Run 4-67-St. Clair after reviewing videotapes and Phase II walk-through inspection reports. The purpose of the in-depth inspection 12

13 was to provide additional information to assess the structural condition of the sewer. This information can also be used for the design of the sewer rehabilitation. The in-depth inspections included data collection and entry into inspection logs, closed circuit televised recording of the inspection and color photographs at critical locations. Probing was also performed on Sewer Run 4-67-St. Clair to determine the extent of voids of the backfill soils around the combined sewer. Structural condition scores from the inspection reports were evaluated and the segments were rated by using the sewer condition rating matrix shown in Table 5. The number of structural condition scores for each segment is tabulated in Tables 6, 7, and 8. Tables 6, 7, and 8 present the sewer inspection results in the form of a sewer condition rating for the Phase I walk-through inspections, Phase II walk-through inspections and Phase II pan-and-tilt TV inspections, respectively. Table 9 presents the sewer condition rating for sewer segments with scores of 2, 3, and 4, the internal and external factor adjustment and the resultant overall structural grade. The sewer segments with the highest overall structural grades, 4 or 5, are the segments most in need of rehabilitation. Because it is more cost-effective to rehabilitate entire sewer runs than to rehabilitate individual sewer segments, priority ratings of sewer runs were developed. To develop the priority rating, each segment s overall structural grade was multiplied by its length. These products were totaled and then divided by the total length of the sewer run. This gives the sewer run a weighted average of overall structural grades which is considered to be the priority rating. The sewer runs are listed in Table 10 in the priority of sewer runs most in need of rehabilitation. Figure 6 illustrates the quantity and proportion, by length, of the combined sewers overall structural grade and Appendix A is a comprehensive spreadsheet providing the characteristics and overall structural grades of the combined sewers. K. Rehabilitation Projects Three sewer runs have been identified for early action rehabilitation projects under the Combined Sewer Infrastructure Assessment Project during Phase I and Phase II. Two of the sewer runs, 5-32-Sherman and 4-21-Adler, were rehabilitated with a cured-in-place pipe. The third run, 4-66-Marion, is being rehabilitated with a fiberglass reinforced pipe. Bid prices are listed in Table

14 Figure 7. The locations of the sewer runs most in need of rehabilitation on Table 10 are shown in L. Rehabilitation Replacement Plan The final recommendations for the priority of the rehabilitation projects were based on the following criteria: Cost-effectiveness. Installation issues. Impact on sewer hydraulics. Materials and durability issues. Table 12 provides a review of rehabilitation alternatives with each alternative s installation issues, impact on hydraulics and material and durability issues. A probable construction cost opinion of each rehabilitation alternative was developed for various sewer sizes and is shown in Table 13. The probable construction cost opinions were calculated on a per foot basis and data to develop them are provided with the table. The probable construction cost opinion is based on actual bids, unit costs from vendors that have contracted for rehabilitation work for the City of Indianapolis and the June 1996 Engineering News-Record Construction Cost Index (ENRCCI = 5600). Figure 8 shows the graph used to prepare opinions of probable construction costs for digand-replace rehabilitation. The pipeline costs are based on actual bids and include pipe, manholes, bedding, excavation, backfill, pavement restoration, and dewatering and were reviewed with a local sewer contractor. Figure 9 shows the graph used to prepare opinions of probable construction costs for fiberglass reinforced pipe liner rehabilitation. The liner costs are based on actual bids and include pipe, insertion pit, grouting and installation. Opinions of probable construction costs are preliminary and to determine a final opinion of costs, a detailed design for each rehabilitation project should be performed. A comparison of each rehabilitation alternative was performed and is included in Table 14. This table shows the advantages and disadvantages of the rehabilitation alternatives. The results of the inspection and assessment of the sewers (Table 10) were analyzed and the 14

15 sewers were further ranked using the logic diagram shown on Figure 10. Table 15 lists the rehabilitation projects in order of priority. Recommended method of rehabilitation and opinion of probable construction costs are shown in the table. The flowchart on Figure 11 was used to select the rehabilitation alternative for each sewer segment. Opinions of probable construction costs in this table were based on information from Table 11 and Table 13. Note, all dig-and-replace projects are relatively shallow with a depth of cut less than 15 feet. M. Inspection Program The Inspection Program includes all sewers not recommended for rehabilitation. Since most of the sewers were recently inspected, it is recommended that the Inspection Program be initiated at the completion of the rehabilitation program in Sewers to be inspected include all sewers not inspected due to having a low consequence of failure, all sewers rehabilitated between 1986 and 1994, and sewers with Overall Structural Grade scores of 3, 2 or 1. To minimize inspection costs yet provide a manageable inspection program, a five year program was developed. Geographic regions were identified for each of four years to perform walk-through inspections. During the fifth year, the inspection consultant would inspect the sewers using pan-and-tilt TV inspections for sewers with flows too high for walk-through inspections or sewers with toxic gases. Figure 12 is a flowchart that provides the logic sequence used to develop the inspection program. Table 16 shows the sewer segments to be inspected and a schedule with an opinion of probable inspection cost. N. Summary and Results The results of the Combined Sewer Infrastructure Assessment Project are: 1) Approximately 71,140 feet of combined sewers that are 60-inch diameter and larger have been identified for rehabilitation. 2) Four early action rehabilitation projects for a length of 2,509 feet have been identified and initiated. 3) Recommendation of an Early Action Rehabilitation Project for Sewer Run 4-67-St. Clair was identified. This pipe replacement project has an engineer s opinion of probable construction cost of $930,

16 4) Final walk-through inspection and pan-and-tilt inspection totals included 256,612 feet (or 71.6%) of the 358,249 feet of 60-inch diameter combined sewers. A total of 253,359 feet of sewers were assessed for rehabilitation. The remaining 3,253 feet of sewers were not assessed because they are in the process of rehabilitation. 5) Of the 253,359 feet of sewer that were assessed for rehabilitation, 71,139 feet, or 28.1%, are in a condition that require rehabilitation. Of that total, 21,702 feet are determined to be in severe condition. 6) Tables 17 and 18 include a graphic representation of the synopsis of the combined sewers to be rehabilitated by pipe material and by pipe sizes. 7) A final opinion of probable total project capital cost is shown in Table 15. A 50% allowance to the unit costs shown in Table 13 has been added for engineering, legal, administration, etc. The following is a tabulation of the probable project cost for the recommended rehabilitation of combined sewers 60" and larger for the area studied: Sewer Rehabilitation Method Length (Feet) Cost Opinion 1 A. CONSTRUCTION COSTS Shotcrete 22,812 $6,600,000 Dig and Replace 22,650 14,330,000 Cured-in-Place Pipe 4,051 1,930,000 Fiberglass Reinforced Pipe Liner 21,626 17,350,000 B. OTHER COSTS Subtotal Construction Cost 71,139 $40,210,000 Mobilization, Bypass Pumping, Hauling, Heavy Cleaning, Disposal, Manhole Rehabilitation 15% 6,030,000 Administration 5% 2,010,000 Design and Construction Engineering 10% 4,020,000 Legal and Financial 5% 2,010,000 Contingency 15% 6,030,000 Total Probable Capital Cost $60,310,000 1 The opinion of cost is in 1996 dollars (ENRCCI = 5600). 16