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HomeMy Public PortalAboutExhibit MSD 77B BMP4 - Cost Estimating Metropolitan St. Louis Sewer District BMP 4 – COST ESTIMATING October 5, 2011 Revision: 0 Watershed Facility Planning - SSO Control Plan Development Metropolitan St. Louis Sewer District Jacobs Engineering Group 2350 Market Street 501 North Broadway St. Louis, MO 63103-2555 St. Louis, MO 63102 (314) 768 6200 (314) 335 4000 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating i October 5, 2011 PREFACE Sanitary sewer overflow (SSO) control is a critical component of the Metropolitan St. Louis Sewer District (MSD) Watershed Facility Planning project. MSD has developed a multiyear SSO Control Plan Development (SSOCPD) program to outline a cost-effective approach for eliminating constructed SSO discharges into area receiving streams and mitigating other sanitary sewer capacity issues during wet weather events. To assist this effort, guidance in the form of Technical Memorandums (TMs) and Best Management Practices (BMPs) is utilized. TMs focus on specific activities associated with SSO Control Plan Development; a series of 40 TMs have been prepared and compiled in a companion Technical Memorandum Manual to present the sequence of tasks, describe the approach, and outline the processes integral to accomplishing the objectives of the program. In contrast, BMPs, such as this one, have been developed to document standard procedures for major tasks associated with SSOCPD execution to enable all program participants to follow a consistent approach in performance of these tasks. As of this date, the BMPs below will be utilized in performing work associated with the following aspects of the SSOCPD program: • BMP 1 Alternative Solutions Evaluation • BMP 2 Capacity Evaluation • BMP 3 CCTV and Condition Inspections • BMP 4 Cost Estimating • BMP 5 Design Storm Tool • BMP 6 Flow Monitoring • BMP 7 Flow Monitoring Data Interpretation • BMP 8 I/I Investigations • BMP 9 I/I Prioritization Scope • BMP 10 Modeling (XP-SWMM + HYDRA) • BMP 11 MSD Design Requirements / Construction Specifications • BMP 12 Preliminary Studies • BMP 13 Priority Ranking System • BMP 14 Project Database • BMP 15 Project Definitions • BMP 16 Pump Station Data • BMP 17 Radar Rainfall Data • BMP 18 Rehabilitation Evaluation • BMP 19 Report Development Guide • BMP 20 Shared Electronic Workspace • BMP 21 SSO Control Master Plan Preparation • BMP 22 Updating Constructed SSO Database • BMP 23 Updating Facility Maps • BMP 24 Watershed SSO Control Plan Report Preparation • BMP 25 WWTF Service Area SSO Control Plan Report Preparation Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating ii October 5, 2011 TABLE OF CONTENTS 1.0 PURPOSE .................................................................................................................... 1 2.0 AUDIENCE ................................................................................................................. 1 3.0 RESOURCES .............................................................................................................. 1 4.0 DESCRIPTION ........................................................................................................... 2 4.1 Overview ...................................................................................................................... 2 4.2 Category Construction Cost Estimate ...................................................................... 5 4.2.1 New Sewer ...................................................................................................... 5 4.2.2 Sewer Rehabilitation ..................................................................................... 6 4.2.3 Tunnel ............................................................................................................. 7 4.2.4 Special Feature .............................................................................................. 7 4.2.5 Storage Facility .............................................................................................. 8 4.2.6 Pump Station ................................................................................................. 8 4.2.7 Public I/I Reduction .................................................................................... 10 4.2.8 Private I/I Reduction ................................................................................... 11 4.3 Conceptual Project Capital Cost Estimate ............................................................. 11 4.3.1 Construction Costs ...................................................................................... 11 4.3.2 Additional Project Costs ............................................................................. 12 4.4 Net Present Worth Analysis ..................................................................................... 13 4.4.1 Considerations ............................................................................................. 13 4.4.2 Details ........................................................................................................... 13 4.5 Existing MSD Projects with Outdated Cost Estimates ......................................... 14 4.6 Comparative Cost Analysis ...................................................................................... 16 Appendices Appendix A Flowchart 2. Process for Developing Conceptual Project Cost Estimates Appendix B Data Entry Form Appendix C CPCE Report Example Appendix D CPCE Summary Report Appendix E New Sewer Construction Unit Cost Charts Appendix F Sewer Rehabilitation Construction Unit Costs Appendix G Storage Facility Construction Unit Cost Curves Appendix H Pump Station Facility Construction Cost Curve Appendix I Forcemain Construction Unit Cost Chart Appendix J I/I Reduction Unit Costs Appendix K CIPRO Pay Items Used in Cost Estimating Database Appendix L Computations/Assumptions: Construction Costs – Net Present Worth Revision Summary Revision Date Comments 0 10/05/11 Draft BMP for comment Doc. Ref.: C5X59901/40004/BMP04 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 1 October 5, 2011 1.0 PURPOSE The purpose of BMP 4 – Cost Estimating is to assist in the development and documentation of standardized construction cost estimates and a capital cost estimate for each conceptual project. This BMP is intended to complement the requirements presented in BMP 15 – Project Definitions, TM 32 – Develop Conceptual Watershed Project Definitions, and TM 33 – Develop Conceptual Watershed Cost Estimates. A number of estimating tools are appended to this BMP to facilitate/document the development and uniformity of cost estimates for various types of projects. The cost estimates developed under the guidance of this BMP are necessary for subsequent efforts associated with the evaluation, recommendation, and prioritization of watershed improvement alternatives, the production of watershed reports, and future design efforts. 2.0 AUDIENCE The primary users of this Cost Estimating BMP are the Cost Estimating Lead, Engineers, Watershed Management (WM) Teams, and Service Area/Watershed (SA/W) Teams. All may use this BMP to develop/document construction cost estimates and capital cost estimates for conceptual projects utilizing the cost estimating tools discussed herein, the cost information contained in Appendices A through L, and the Conceptual Project Descriptions developed in accordance with BMP 15 – Project Definitions. 3.0 RESOURCES The Cost Estimating Database, together with BMP 15 and the various conceptual cost estimating materials referenced herein and collected in Appendices A through L, are the principal resources to assist in the development and support of cost estimates. Additional resources available to users of this BMP include the following personnel: • William Haag – Cost Estimating Lead (Jacobs) E-mail: william.haag@jacobs.com Phone: 314-335-4066 • Mark Beumer – Section Manager (Jacobs) E-mail: mark.beumer@jacobs.com Phone: 314-335-4121 • Philip Ewing – Cost Estimating Database Administrator (Jacobs) E-Mail: philip.ewing@jacobs.com Phone: 314-335-4027 • Tony Tawa – Project Engineer (Jacobs) E-mail: tony.tawa@jacobs.com Phone: 314-335-4196 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 2 October 5, 2011 4.0 DESCRIPTION The purpose of developing cost estimates during Activity 331 is to enable their subsequent utilization during the evaluation, development, and prioritization of various sanitary system improvements. In addition to using these estimates to compare potential watershed solutions, these estimates are also used in later Activities to compare alternatives with projects in other watersheds and Service Areas; it is also possible that MSD will eventually use these estimates to prepare budget forecasts. Consequently, it is critical that all WM Teams prepare cost estimates using the same methodology, unit costs, and baseline year regardless of when the estimates are actually prepared. This BMP establishes that methodology, provides the unit costs to be used, and establishes the baseline year. With respect to methodology, this BMP describes the process that SA/W and WM Teams need to follow in developing cost estimates for new and previously defined conceptual projects. The discussion is divided into four areas. Subsection 4.1 provides an overview of the entire effort, including a review of predecessor/successor activities and a discussion of cost estimate development components and terminology. Subsection 4.2 focuses on the preparation of construction cost estimates for various infrastructure and/or system improvement categories that may be associated with a project and discusses the various unit costs that are to be used. Subsection 4.3 explains how these construction cost estimates are used to determine additional costs associated with a project; the discussion also describes how the various cost components are used to develop the project’s overall cost referred to as the ‘Conceptual Project Capital Cost’. Every Conceptual Project Capital Cost developed using this BMP reflects a 2011 baseline year. Subsection 4.4 describes the methodology to develop a standardized net present worth for each project. Comparison of previously developed cost estimates to those prepared using the methodology presented herein is discussed in Subsection 4.5. Subsection 4.6 briefly explains how the project cost estimates developed in accordance with the requirements of this BMP are utilized in subsequent tasks. Discussions in all six of these subsections are supported by materials presented in BMP 15 and by a variety of cost estimating tools attached as Appendices A through L; the use of these resources is integrated into the discussion of cost estimating procedures presented below. 4.1 Overview Although the first two-thirds or so of the TMM discusses Activities that are directed toward assessing sanitary system conditions and problems, the remainder of the TMM is concerned with the primary objective of the SSOCPD effort – developing approaches to address identified problems and preparing an explicit plan to correct system deficiencies. This effort involves several steps as described in TMs 27 through 40. Activities 27 through 30 generally focus on infiltration/inflow (I/I) removal and system hydraulics. Activities 31 through 35 implement the process of transitioning from identifying potential solutions that address sanitary system concerns to preparing a recommended list of watershed projects; these Activities 1 Activity 33 – Develop Conceptual Watershed Cost Estimates Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 3 October 5, 2011 (especially Activities 32 and 33) are discussed further in the following paragraphs. Finally, Activities 36 through 40 are associated with prioritizing watershed projects and integrating them into a comprehensive Service Area implementation plan. During Activity 312, various watershed-wide alternatives (including possible components such as I/I reduction, storage, additional conveyance capacity, etc.) to address sanitary system concerns are identified. The potential infrastructure improvements for each watershed-wide alternative are refined during Activity 323 to create well-defined ‘conceptual projects4’. As discussed in BMP 15, there are three sources of conceptual projects: (1) new projects developed by the WM Team; (2) existing MSD conceptual projects with revised scopes/quantities and/or inadequate cost estimates; and (3) existing MSD conceptual projects with validated scopes, quantities, and cost estimates. Cost estimates for these three types of projects are developed and escalated as necessary during Activity 33. During Activity 345 the Conceptual Project Descriptions and Conceptual Project Cost Estimates are evaluated using criteria and guidance set forth in BMP 1 – Alternative Solutions Evaluation to (1) develop the final preferred combination of conceptual projects for each alternative that achieve watershed objectives, and (2) select the preferred watershed-wide alternative. The conceptual projects for the preferred alternative are structured into more formal projects during Activity 356. Development of Conceptual Project Descriptions and associated cost estimates during Activities 32 and 33 are critical intermediate steps in the process of progressing from identifying potential sanitary system solutions to preparing a recommended list of watershed projects. These two Activities are structured to interact with each other and to achieve standardized outcomes. This is accomplished through adherence to uniform requirements, procedures, and templates for the performance of Activities 32 and 33 set forth in TM 32/BMP 15 and TM 33/BMP 4 (this BMP), respectively. As expanded on below, the project descriptions prepared in Activity 32 are developed to a level appropriate for preparing subsequent cost estimates during Activity 33; a Cost Estimating Database has been created to support the performance of both Activities. As noted in BMP 15, the standardization and close correlation between the two Activities limits the ability to adjust or refine cost estimates for projects to reflect nonstandard features or special considerations. Although atypical project elements are not captured in the cost estimates unless of significant consequence, the materials prepared during Activity 32 do allow for documenting these aspects so that they can be factored into subsequent evaluations. 2 Activity 31 – Identify Improvement Alternatives to Meet Watershed Goals 3 Activity 32 – Develop Conceptual Watershed Project Definitions 4 As used in this BMP, the term ‘conceptual project’ refers to sanitary projects listed in MSD’s CIPRO or Oracle database, except for those projects at or beyond the stage at which the District has appropriated funds for Construction. Thus conceptual projects may include, but are not limited to, projects that were identified in a Master Plan or SKME Report, projects described by preliminary studies, and projects that are at various design stages but have not yet been authorized for construction. 5 Activity 34 – Evaluate Watershed Improvement Alternatives 6 Activity 35 – Recommend List of Watershed Improvement Projects Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 4 October 5, 2011 Development of project definitions and associated cost estimates are facilitated by describing and quantifying a project in terms of eight major construction categories that may be relevant components. The categories are (1) New Sewer, (2) Sewer Rehabilitation, (3) Tunnel, (4) Special Feature, (5) Storage Facility, (6) Pump Station, (7) Public I/I Reduction, and (8) Private I/I Reduction. Any combination of these eight categories is available to define a project. During Activity 32 quantities and other information are documented for all relevant categories associated with a project. More specifically, a Conceptual Project Description (CPD) consisting of four elements – Project Identification, Project Definition, Project Information and Background, and Project Exhibit – is prepared using the Data Entry Form associated with the Cost Estimating Database (see BMP 15). This information is used in a two-part process during Activity 33. During the first part of the estimating process, a construction cost estimate is generated for each relevant construction cost category as described in Subsection 4.2; these costs are termed ‘category construction costs’ in this BMP for ease of reference. During the second part of the estimating process, these category construction costs are used to derive other project cost components and to determine both a Conceptual Project Capital Cost as described in Subsection 4.3 and a Conceptual Project Net Present Worth as described in Subsection 4.4. Utilization of these cost estimates, including adjustments and comparisons to other cost estimates are briefly discussed in Subsections 4.5 and 4.6. The cost estimating process is summarized on the decision matrix flowchart presented in Appendix A. Costs corresponding to the two parts of the estimating process cited above are generated and documented using a two-part report referred to as the Conceptual Project Cost Estimate (CPCE) Report. The CPCE Report is one of two principal reports associated with the Cost Estimating Database. The other principal report is the Conceptual Project Description Report as described in BMP 15. The Cost Estimating Database is structured such that completion of the Data Entry Form provides all the information needed to produce both of these reports. Most of that information is replicated on the CPD Report and is used internally to calculate the cost estimate results presented on the CPCE Report. A few items are specific only to the CPCE Report; data entry labels associated with these fields are listed below and are shaded in green on the Data Entry Form illustrated in Appendix B. Location on Conceptual Project Data Field Name Entry Form (Form Tab Name / Heading) Description . Unit Cost ($/lf) Project Definition 1 / Tunnel See Article 4.2.3.b. Construction Cost ($) Project Definition 1 / Special Feature See Article 4.2.4.b. NPW Factor Project Definition 1 / Special Feature See Article 4.2.4.c. NPW Factor Project Definition 2 / Pump Station (Facility) See Article 4.2.6.d. Unit Cost – Other Project Definition 3 / Private I/I Reduction See Article 4.2.8.a. Cost Estimate Year Documentation – Activity 33 See BMP 15 Appendix D Description Misc. Cost Info. / Land Acquisition Cost See Article 4.3.2. Land Acquisition ($) Misc. Cost Info. / Land Acquisition Cost See Article 4.3.2. Description Misc. Cost Info. / Environmental Mitigation Cost See Article 4.3.2. Mitigation Costs ($) Misc. Cost Info. / Environmental Mitigation Cost See Article 4.3.2. Description Misc. Cost Info. / Excessive Utility Conflict Cost See Article 4.3.2. Utility Conflict Costs ($) Misc. Cost Info. / Excessive Utility Conflict Cost See Article 4.3.2. Existing Project Cost Estimate Misc. Cost Info. / Existing Cost Estimate See Subsection 4.5. Year Misc. Cost Info. / Existing Cost Estimate See Subsection 4.5. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 5 October 5, 2011 Year Misc. Cost Info. / Future Escalation See Subsection 4.6. Escalation Yr ENR CCI Number Misc. Cost Info. / Future Escalation See Subsection 4.6. The CPCE Report is a working document intended to assist in the performance of subsequent SSOCPD activities. An example illustrating the organization of the CPCE Report is presented in Appendix C; although hypothetical, the ‘project’ presented therein includes components that encompass all eight construction categories for illustration. This is the same ‘project’ that was used as an example to illustrate the CPD Report in BMP 15. A reader-friendly abstract of the CPCE Report referred to as the ‘CPCE Summary Report’ is illustrated in Appendix D. 4.2 Category Construction Cost Estimate The steps presented in this Subsection outline the process that is used to identify a project and generate category construction cost estimates for all conceptual projects, including new projects, existing projects with revised scopes, and existing projects with validated scopes7. The only items required for project identification are Project Name and associated Service Area, Watershed, and Record ID. All four of these items are automatically copied into the CPCE Report based on information entered in the Data Entry Form. Project identification information is recorded on all pages of the CPCE Report. A category construction cost for a project represents the construction cost estimate for a specific construction category exclusive of contingencies. Category construction cost estimates are developed separately for each of the eight major construction categories noted above that may be associated with a project. With the exception of tunnel construction, special feature entries, and undefined (i.e., ‘Other’) private I/I reduction, all unit costs needed for development of cost estimates are embedded in the Cost Estimating Database. Consequently, development of the category construction cost estimate typically occurs automatically once quantifiable aspects of the Conceptual Project Description have been entered into the database via the Data Entry Form. Part 1 of the CPCE Report is used to document these quantities and relevant unit costs, and present the resultant extended costs and category construction costs. (An extended cost is simply the result obtained by multiplying the item quantity by the associated unit cost; the sum of extended costs for a category represents the category construction cost.) Development of the category construction cost for each of the eight construction categories is presented in turn below. 4.2.1 New Sewer a. Using selected Project Definition information entered into the Cost Estimating Database during Activity 32, relevant new sewer fields in Part 1 of the CPCE Report are automatically populated. Data presented includes sewer type (sanitary, storm, or combined), pipe diameter (inches), average trench depth (feet), trench cover type (sod or pavement), and installation length (feet). A separate entry (row) is displayed for each 7 Refer to Subsection 4.5 for additional tasks performed for existing conceptual projects with validated, but outdated, cost estimates. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 6 October 5, 2011 combination of variables (pipe size / trench average depth / trench cover type) associated with the conceptual project. b. Once all quantity information has been provided (including sewer type and type of cover), the Cost Estimating Database automatically determines the appropriate unit cost, calculates an extended cost for each entry, and sums these extended costs to obtain a New Sewer Construction Cost estimate. More specifically, for each new sewer entry created on the Data Entry Form, the corresponding unit cost ($/linear ft) is automatically retrieved via the ‘Run Macro!’ button for use and display on the CPCE Report; the value associated with this retrieved cost is based on the ‘New Sewer Construction Unit Cost Charts’ located in Appendix E. c. Note: New Sewer Construction Unit Cost Charts for diameters 90 inches and smaller were prepared by MSD and Jacobs primarily using MSD CIPRO Database values, with adjustments at greater depths to account for increased construction complexity; these costs were used to develop line- of-best-fit cost projections at each applicable depth for diameters greater than 90 inches. Costs are based on the assumption that polyvinyl chloride pipe was used for diameters 36 inches or smaller, and that reinforced concrete pipe was used for diameters larger than 36 inches. The conceptual unit costs include appurtenances typically associated with sewer construction (manholes, connections, etc.), as well as ancillary construction costs for aspects such as mobilization, typical utility relocation, and site protection/restoration. However, as noted in BMP 15, they do not include rock excavation, dewatering, junction chambers, or easement acquisition. If these excluded aspects represent a major element of the project they should be addressed using the Special Feature construction category; as a rule of thumb, if their impact to the resultant Conceptual Project Capital Cost would be less than 15% they can be ignored. 4.2.2 Sewer Rehabilitation a. Using selected Project Definition information entered into the Cost Estimating Database during Activity 32, relevant sewer rehabilitation fields in Part 1 of the CPCE Report are automatically populated. Data presented includes pipe diameter (inches), length (feet), quantity of point repairs, and quantity of impacted service laterals. A separate entry (row) is displayed for each sewer diameter being rehabilitated as part of the project. b. The cost of sewer rehabilitation for each pipe size diameter being lined consists of three components: sewer lining, point repairs, and impacted service lateral repairs. Once all quantity information has been entered, the Cost Estimating Database will utilize unit costs specific to each of these three components, calculate an extended cost for each listed pipe diameter, and sum these extended costs to obtain a Sewer Rehabilitation Construction Cost estimate. More specifically, for each sewer rehabilitation entry associated with the project, the corresponding unit cost Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 7 October 5, 2011 ($/linear ft) for that diameter is automatically obtained from unit costs for liner repair embedded in the Cost Estimating Database; unit costs for point repairs and impacted service laterals are similarly retrieved. These unit costs are documented at ‘Sewer Rehabilitation Construction Unit Costs’ located in Appendix F. c. Note: The Sewer Rehabilitation Construction Unit Costs tabulation was prepared by MSD and Jacobs primarily using MSD CIPRO Database values; additional details are presented in Appendix F. 4.2.3 Tunnel a. Using selected Project Definition information entered into the Cost Estimating Database during Activity 32, relevant tunnel fields in Part 1 of the CPCE Report are automatically populated. Data presented includes tunnel diameter (feet) and length (feet). If there is more than one tunnel or tunnel diameter associated with the project, additional rows are displayed. b. Unlike other construction categories, unit cost information for tunnels has not been developed. Consequently, tunnel unit costs ($/linear ft) need to be developed by WM Teams on a case-by-case basis due to the potential for significant variables such as depth, number of access shafts, and type of subsurface material. Include any ancillary construction costs such as mobilization, typical utility relocation, and site protection/restoration in the unit costs; do not include land acquisition costs, as they are addressed separately at Part 2 of the CPCE Report. Contact the Section Manager to identify resources available to assist in determining tunnel costs and related considerations. ‘Tunnel Unit Cost’ information is manually entered at the same-named field on the ‘Project Definition 1’ tab of the Data Entry Form (see Appendix B). c. Once all unit cost information has been entered, the Cost Estimating Database will automatically calculate an extended cost for each entry, and sum these extended costs to obtain a Tunnel Construction Cost estimate. 4.2.4 Special Feature a. Using selected Project Definition information entered into the Cost Estimating Database during Activity 32, the ‘Designation’ field associated with the Special Feature category in Part 1 of the CPCE Report is automatically populated. b. Unlike other construction categories, the unit cost approach is not utilized for the Special Feature construction category. Instead the Data Entry Form allows the user to enter the Category Construction Cost associated with the special feature directly at the ‘Construction Cost ($)’ field on the ‘Project Definition 1’ tab of the Data Entry Form (see Appendix B). This cost needs to be developed by WM Teams on a case-by-case basis. For features such as rock excavation and dewatering, cost estimating methods outlined in the Preliminary Studies Guidebook should be consulted. For example if the Special Feature category consisted solely of rock excavation, the WM Team would multiply the estimated volume of rock Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 8 October 5, 2011 (i.e., Class A Excavation) by the Pre-CIPRO unit cost ($180/cubic yard) to determine the cost of this work. Include any ancillary construction costs such as mobilization, typical utility relocation, and site protection/restoration in the value entered at Construction Cost ($). c. Unlike most other construction categories, the Cost Estimating Database allows for adjustment of the Net Present Worth Factor associated with the Special Feature category. Refer to Subsection 4.4, particularly supporting materials, for additional guidance. 4.2.5 Storage Facility a. Using selected Project Definition information entered into the Cost Estimating Database during Activity 32, relevant storage facility fields in Part 1 of the CPCE Report are automatically populated. Data presented includes facility type and volume (gallons). If there are multiple storage tanks associated with the project, a separate entry is displayed for each one. b. For each storage tank entry, the Cost Estimating Database automatically calculates the corresponding unit cost ($/gallon). The unit cost is based on storage volume and facility type, and is associated with the respective best fit equation illustrated by the ‘Storage Facility Construction Unit Cost Curves’ located in Appendix G. c. Once all unit cost information has been calculated, the Cost Estimating Database automatically calculates an extended cost for each entry, and sums these extended costs to obtain a Storage Facility Construction Cost estimate. d. Note: The construction unit cost curve for aboveground storage facilities was prepared by Jacobs using cost information provided by two manufacturers of prestressed concrete water storage tanks (Natgun Corporation and Preload Inc.) and preliminary cost estimates regarding wastewater storage facilities prepared for MSD Project No. 2003083 by Crawford, Murphy & Tilly, Inc. The construction unit cost curve for underground storage facilities was developed utilizing bid prices for projects nationwide by the U.S. Environmental Protection Agency8; those values have been escalated/adjusted as appropriate utilizing the ENR CCI9 to represent 2011 unit costs. The conceptual unit costs include fencing, driveway access, some site grading, maintenance vehicle parking, and other facilities common to MSD storage facilities, but do not include rock excavation, dewatering, extensive site work, or land acquisition. 4.2.6 Pump Station a. Using selected Project Definition information previously entered into the Cost Estimating Database during Activity 32, relevant pump station fields 8 See Manual: Combined Sewer Overflow Control, United States Environmental Protection Agency Office of Research and Development, EPA/625/R-93/007, September 1993, p. 94. 9 Engineering News Record (ENR) Construction Cost Index (CCI) Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 9 October 5, 2011 in Part 1 of the CPCE Report are automatically populated. Data entered includes peak design flowrate (mgd), forcemain diameter (inches), cover type (sod or pavement), and forcemain length (feet). If there is more than one pump station or set of forcemain conditions associated with the project, additional rows are used; for varying forcemain conditions associated with a single pump station, make sure that pump station information is not replicated in the rows used to present additional forcemain data. Costs of any gravity sewers beyond the limits of the conceptual pump station facility should be determined as described in Article 4.2.1. b. As discussed in BMP 15, the Pump Station construction category portion of the Data Entry Form distinguishes between the facility component and the forcemain component. Once all quantity information has been entered (including type of cover), the Cost Estimating Database automatically calculates or retrieves the unit cost for each entry and separately calculates facility and forcemain costs. More specifically, for each pump station flowrate entry created on the Data Entry Form, the corresponding facility cost ($) is automatically calculated; this calculated entry is associated with the best fit equation illustrated by the ‘Pump Station Facility Construction Cost Curve’ located in Appendix H. Similarly, for each unique forcemain entry on the Data Entry Form, the corresponding forcemain unit cost ($/linear ft) is automatically retrieved via the ‘Run Macro!’ button for use and display on the CPCE Report; the value associated with this retrieved cost is based on the ‘Forcemain Construction Unit Cost Chart’ located in Appendix I. The appendix contains two sets of Forcemain Construction Unit Cost plots separately representing 6 thru 48 diameter pressure pipe under sod and under pavement. c. Once all unit cost information has been determined, the Cost Estimating Database automatically calculates a facility cost and/or forcemain cost for each entry, separately sums these two category cost components to obtain a Facility Cost and a Forcemain Cost for the project. Collectively, these two costs together represent the Pump Station Construction Cost. d. Unlike most other construction categories, the Cost Estimating Database allows for adjustment of the Net Present Worth Factor associated with the facility aspect of pump stations. Refer to Subsection 4.4, particularly supporting materials, for additional guidance. e. Note: The Pump Station Facility Construction Cost Curve was prepared by Jacobs using cost data associated with construction of selected facilities, EPA cost curves, and other published information to develop and plot an adjusted best-fit equation; the adjusted cost curve reflects a 2011 baseline year. The conceptual unit costs for the facility include fencing, driveway access, some site grading, a backup generator, 4 hours of storage, maintenance vehicle parking, telemetry, and other facilities common to MSD pumping stations. The facility cost is based on a submersible type pump station. Forcemain construction unit costs were prepared by Jacobs using MSD ‘Engineer’s Cost Estimates’ for various projects; the estimates Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 10 October 5, 2011 were prepared during the past decade. The conceptual unit costs for the forcemain include appurtenances such as restraints, valve boxes, and air release valves. The facility unit costs and forcemain unit costs also account for ancillary construction expenses such as mobilization, typical utility relocation, and site protection/restoration, but do not include costs for rock excavation, dewatering, junction chambers, extensive site work, or land acquisition. 4.2.7 Public I/I Reduction a. Using selected Project Definition information entered into the Cost Estimating Database during Activity 32, applicable public I/I reduction items in Part 1 of the CPCE Report are automatically populated. Unit costs for the ten public I/I reduction items are already embedded in the Cost Estimating Database; these respective unit costs are documented in Appendix J. Once all quantities have been entered, the Cost Estimating Database will automatically calculate an extended cost for each entry, and sum these extended costs to obtain a Public I/I Reduction Construction Cost estimate. b. As discussed in BMP 15, the Public I/I Reduction construction category portion of the Data Entry Form distinguishes between tthe sewers component and the manholes component. Once all quantities have been entered, the Cost Estimating Database will automatically retrieve the unit cost and calculate an extended cost for each entry. The database will also separately sum the extended sewer item costs to obtain a Public I/I Reduction (Sewers) Construction Cost estimate and a Public I/I Reduction (Manholes) Construction Cost estimate. c. Note: Public I/I Reduction unit costs were developed jointly by MSD and Jacobs using data from a variety of sources including adjusted contractor bid prices for recent District projects (sewer defects and selected manhole defects), in-house work order costs (manhole structure rehabilitation), CIPRO Pay Item prices (manhole frame defects), and I/I vendor estimates (manhole cover missing bolts). Refer to Appendix J for additional details and assumptions and Appendix K for a listing of current CIPRO pay items associated with unit costs used in the Cost Estimating Database. All unit costs are assumed to be representative of the 2011 baseline year, and include ancillary construction costs for items such as mobilization, typical utility relocation, and normal site protection/restoration. d. As noted in BMP 15, certain projects may involve baseline I/I removal in areas that lack a precedent I/I investigation. Baseline I/I defect removal in such circumstances is referred to in the Cost Estimating Database as Projected I/I Reduction, and the associated cost is subsequently reported using a ‘Projected I/I Reduction’ line item. Project I/I Reduction is assumed to remove a portion of both public and private I/I defects. Refer to Appendix J for additional details and assumptions associated with development of Projected I/I Reduction costs. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 11 October 5, 2011 4.2.8 Private I/I Reduction a. Using selected Project Definition information entered into the Cost Estimating Database during Activity 32, applicable private I/I reduction items in Part 1 of the CPCE Report are automatically populated. Unit costs for the six relevant private I/I reduction items are embedded in the Cost Estimating Database; the respective unit costs are documented in Appendix J. Unit costs will need to be developed and entered for any I/I reduction approaches that are not listed; this unit cost information for ‘Other: ____’ I/I reduction measures is manually entered directly below the identification of the approach on the ‘Project Definition 3’ tab of the Data Entry Form (see Appendix B). Once all quantities have been entered, the Cost Estimating Database will automatically calculate an extended cost for each entry, and sum these extended costs to obtain a Private I/I Reduction Construction Cost estimate. b. Note: Private I/I Reduction unit costs were developed jointly by MSD and Jacobs in a series of workshops using contractor bid prices from recent District projects and are representative of the 2011 baseline year. Refer to Appendix J for additional details and assumptions. The unit costs do not include the costs for private property releases, extensive site restoration, or other special agreements. c. Refer to Paragraph 4.2.7.d. for discussion associated with deriving costs for private I/I reduction in areas without a precedent I/I investigation. 4.3 Conceptual Project Capital Cost Estimate Following development of the category construction cost estimate(s), Part 2 of the CPCE Report is used to present the Conceptual Project Capital Cost (discussed in this subsection), the project’s Net Present Worth (Subsection 4.4), comparison with outdated existing cost estimates (Subsection 4.5), and future escalation of the Conceptual Project Capital Cost (Subsection 4.6). Part 2.A. of the CPCE Report summarizes the various category construction cost estimates and the associated construction contingencies and ancillary project expenses (i.e., engineering and, if applicable, land acquisition). The Cost Estimating Database uses the category construction cost estimates developed during the activities described in Subsection 4.2 as the starting point for determination of these additional costs, and is able to accommodate single or multiple categories associated with a project in any combination in performing the necessary computations. The Total Construction Cost and Net Present Worth for each category are also displayed at Part 2.A., together with respective project totals contributing to the Conceptual Project Capital Cost and the Conceptual Project Net Present Worth. The methodology and tools used to account for these additional costs and expenses and to obtain the Conceptual Project Capital Cost estimate are described below. 4.3.1 Construction Costs Part 2.A.1. of the CPCE Report is used to present the Category Construction Cost, Construction Contingency, Total Construction Cost, and Net Present Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 12 October 5, 2011 Worth for each of the eight construction categories (i.e., New Sewer, Sewer Rehabilitation, Tunnel, Special Feature, Storage Facility, Pump Station, Public I/I Reduction10, and Private I/I Reduction11). The Category Construction Cost for each category is multiplied by a contingency factor to obtain a Construction Contingency for the category. When added to the Category Construction Cost, the Construction Contingency value produces that category’s Total Construction Cost. The database sums the Category Construction Cost, Construction Contingency, and Total Construction Cost for each of the eight categories to obtain the project totals for these three cost components. 4.3.2 Additional Project Costs Part 2.A.2. of the CPCE Report is used to present Additional Project Costs. Additional Project Costs include Engineering costs and certain types of infrequently encountered major costs. Engineering costs are calculated separately for each construction category and added to any applicable major costs to obtain the Additional Project Cost. Engineering costs includes expenses incurred by the District for activities such as legal and administrative functions, surveys, geotechnical investigations, preliminary studies and construction services, as well as engineering. Generally it is calculated for each construction category as a designated percentage of that category’s Total Construction Cost. For projects that include a Private I/I Reduction component based on investigated defects, no engineering costs are developed for this construction category, but instead a cost of $2,000 is assessed for each parcel experiencing one or more I/I reduction measures. In determining the quantity of impacted parcels, the Cost Estimating Database makes the simplifying assumption that the value is equal to the total number of private I/I defects. The three types of infrequently encountered major costs considered are land acquisition, environmental mitigation, and extraordinary utility relocations. Land acquisition costs apply only to the Tunnel, Special Feature, Storage Facility, and Pump Station construction categories. Environmental mitigation refers to situations where atypical site work (remediation of contaminated media, construction of compensatory wetlands, etc.) is required. Typical utility relocations are already addressed in the various unit costs described in Subsection 4.2; consequently, excessive utility conflicts only apply to those circumstances where disproportionate utility concerns exist. MSD has recently (December 2009) developed a Utility Cost Estimate spreadsheet that can provide guidance in determining excessive utility conflict costs. Using the ‘Misc. Cost Info.’ tab of the Data Entry Form (see Appendix B), each of 10 Public I/I reduction and private I/I reduction costs for projects lacking a precedent I/I investigation are reported as Projected I/I Reduction cost. Although Projected I/I Reduction is not considered a separate construction category, for purposes of calculating and reporting costs on the CPCE Report its associated costs are handled in the same manner as if it were a ‘ninth’ construction category. 11 See Footnote 10. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 13 October 5, 2011 these three types of costs is handled in a similar manner when they are relevant to a project. An explanation of the circumstances associated with the expense is listed in the ‘Description’ field under the respective heading, together with an associated cost in the accompanying cost field. The Additional Project Cost is added to the Total Construction Cost for the project to obtain the Conceptual Project Capital Cost. The Conceptual Project Capital Cost is subsequently used in the Sanitary Projects Database (see BMP 14 – Project Database). 4.4 Net Present Worth Analysis As noted previously, a major objective in developing Conceptual Project Descriptions and standardized cost estimates is to enable the SA/W and WM Teams to compare two or more alternative solutions, each designed to achieve similar results for an identified problem. A number of factors are involved in these subsequent comparative analyses, as discussed generally in TM 34 – Evaluate Watershed Improvement Alternatives and in detail in BMP 1 – Alternative Solutions Evaluation. One of the most important factors is net present worth. Net present worth refers to a quantification of expenditures or value in terms of present dollars by considering the time value of money, and applying this concept to expenditures and credits incurred during the life expectancy of the improvements. The goal of a net present worth analysis is to calculate the estimated life cycle costs associated with various alternatives in an effort to select the solution with the lowest overall cost. This subsection discusses the methodology that is used by the Cost Estimating Database to determine the Net Present Worth of various conceptual level projects. 4.4.1 Considerations Net present worth analysis allows for inclusion of economic factors beyond initial construction costs as part of the deliberation. Some of the factors that are taken into account in a net present worth analysis are initial capital costs, various life cycle durations, replacement costs, and operation & maintenance (O&M) costs (e.g., treatment costs, pumping costs, manpower, and utilities) associated with competing alternatives. For example, a solution that has greater capital costs may actually be more economical than a low capital cost, high maintenance alternative; a net present worth analysis allows a systematic, economic comparison. Additionally, factors such as the rate of inflation and the interest rate on invested money are important considerations in any net present worth analysis. 4.4.2 Details The net present worth computations performed by the Cost Estimating Database enable a comparison of capital and anticipated operation and maintenance costs over the life expectancy of the competing improvements. The results of net present worth computations for a project are displayed at Part 2.A.1. of the CPCE Report. The various parameters, computations, and assumptions utilized by the database in developing the displayed Net Present Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 14 October 5, 2011 Worth values are discussed below. The discussion is supported by Tables L1 and L2 in Appendix L. Table L1 summarizes the various calculations used by the Cost Estimating Database to obtain various costs and produce the Net Present Worth for each construction category and the Conceptual Project Net Present Worth. Table L2 documents the various assumptions used to determine annual costs and replacement costs for each construction category and illustrates how these assumptions were quantified. Approach and Assumptions. As a starting point, a 50-year planning period is used and capital expenditures are assumed to occur at year zero. Any O&M costs associated with the various construction categories are assumed to occur annually throughout this 50-year duration. Replacement costs for selected improvement components are assumed to occur at various intervals depending on the construction category and the replacement item. At the end of the 50- year planning period no replacement or residual land value is considered and, with the exception of tunnels, no credit is given for salvage value. Due to the conceptual and standardized approach used to develop project descriptions and construction costs, and after analyzing relevant data from a variety of sources, simplifying assumptions were used to typically allow representation of annual and replacement costs as a percentage of a category’s total construction cost; the nature of certain categories required additional complexity in some instances. The various assumptions and associated computations are detailed in Table L2. Net Present Worth Economic Formulas. Supporting the basic framework described in the preceding paragraph, two parameters – inflation rate and interest rate – are used in conjunction with standard cash flow factors and formulas to account for the time value of money. More specifically, Uniform Series Present Worth Factor (USPWF) equations are used to account for annual costs and Single Payment Present Worth Factor (SPPWF) equations are used to account for periodic replacement costs. A USPWF equation converts annual expenditures over the planning period to a present worth value. Similarly, an SPPWF equation converts expenditure at a specific point in the future to a present worth value. Critical to the use of these equations is selection of an interest rate. The Cost Estimating Database uses a Real Interest Rate12 ‘i’ of 1.94% in performing net present worth calculations; this is based on an assumed rate of return of 5% and a constant inflation rate of 3%. 4.5 Existing MSD Projects with Outdated Cost Estimates As noted in Subsection 4.1, one of the three sources of conceptual projects is existing MSD conceptual and design projects with validated scopes, quantities, and cost estimates. Generally these validated cost estimates will either have been prepared prior to 2006, or they will have been prepared using costs consistent with the 12 ‘Real Interest Rate’ (i) is equivalent to the ‘Rate of Return on Investment’ (r) minus the ‘Rate of Inflation’ (e). It is calculated as follows: i = (r – e) ÷ (1 + e) Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 15 October 5, 2011 District’s current CIPRO Pay Items tabulations; see Appendix K for additional discussion. Relative to estimates prepared using the unit costs presented in this BMP, some of these validated, existing cost estimates are considered outdated. Escalation of validated cost estimates for existing projects to a 2011 timeframe is required to enable their subsequent comparison to the Conceptual Project Capital Cost estimates for such projects. A common tool used to compare construction costs for different time frames is the Engineering News Record Construction Cost Index. Part 2.B. of the CPCE Report displays escalated costs for existing projects with outdated cost estimates. These escalated costs are determined using the following three-step process: 1. Manually enter the project’s validated ‘Existing Project Cost Estimate’ at the same-named field on the ‘Misc. Cost Info.’ tab of the Data Entry Form (see Appendix B). 2. Manually enter the ‘Year’ (between 1990 and 2011 inclusive) associated with preparation of cost estimate at the same-named field on the ‘Existing Cost Estimate’ portion of the ‘Misc. Cost Info.’ tab of the Data Entry Form (see Appendix B). For estimates from preliminary studies prepared subsequent to 2005 enter ‘2011’. 3. Based on the year entered for the existing cost estimate, the Cost Estimating Database will automatically look up the associated ENR CCI Annual Average value for that year13. Additionally, using the CCI Annual Average value for May 2011 of ‘9035’ (already entered), the Cost Estimating Database will automatically calculate the project’s Escalated Existing Total Cost Estimate for the 2011 baseline year. Part 2.C. of the CPCE Report is used to compare the Conceptual Project Capital Cost to the Escalated Existing Total Cost Estimate; based on information associated with Parts 2.A. and 2.B. of the CPCE Report, the ratio between these two values is automatically calculated. SSOCPD participants should use this information to examine the precision between the two values, and to assess whether the estimates produced using the methodology described in this BMP are compatible with estimates produced for MSD using other approaches. The Cost Estimating Database has been designed to estimate typical costs for a described project, while at the same time accommodating simplicity and standardization. Consequently, the further an actual project varies from the norm, the less likely that the ratio between the Conceptual Project Capital Cost and the Escalated Existing Total Cost Estimate will be close to ‘1.0’. These variations should be examined and taken into account when performing comparative evaluations during later SSOCPD Activities. Depending on various factors (e.g., objective, nature of activity, Program Team guidance) either the Conceptual Project Capital Cost estimate or the more detailed existing cost estimate may be the more appropriate value for use or presentation in a given situation. 13 The ENR CCI Annual Average value used for each of the years between 1990 and 2011 are presented in the Cost Estimating Database’s ‘Ref Costs: ENR CCI Table’. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating 16 October 5, 2011 4.6 Comparative Cost Analysis As noted above, Conceptual Project Capital Cost estimates prepared under the guidance of this BMP represent May 2011 costs. Upon future completion of the SSO Control Plan, each total cost estimate will be updated to a common baseline year; this escalation is not the responsibility of the WM Teams. It is likely that this escalation will be performed using the ENR CCI that exists at that time in a manner similar to the process described in Subsection 4.5. These escalated costs are developed by manually entering the future baseline year and that year’s associated ENR CCI at the ‘Year’ and ‘Escalation Yr ENR CCI Number’ fields on the ‘Future Escalation’ portion of the ‘Misc. Cost Info.’ tab of the Data Entry Form (see Appendix B). From this information the Cost Estimating Database will automatically calculate the project’s Escalated Conceptual Project Capital Cost and the results will be displayed at Part 2.D. of the CPCE Report. Finally, it should be understood that the cost estimates prepared in accordance with this BMP are conceptual in nature. If more detailed cost estimates are required, such as for preliminary studies, other resources such as BMP 12 - Preliminary Studies and the associated Preliminary Studies Guidebook should be consulted. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix A Flowchart 2. Process for Developing Conceptual Project Cost Estimates Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix A – Flowchart 2. Process for Developing Conceptual Project Cost Estimates A-1 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix B Data Entry Form Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix B – Conceptual Project Data Entry Form B-1 October 5, 2011 Appendix B – Data Entry Form Project Definition 1 Tab: Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix B – Conceptual Project Data Entry Form B-2 October 5, 2011 Project Definition 2 Tab: Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix B – Conceptual Project Data Entry Form B-3 October 5, 2011 Project Definition 3 Tab: Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix B – Conceptual Project Data Entry Form B-4 October 5, 2011 Comments Tab: Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix B – Conceptual Project Data Entry Form B-5 October 5, 2011 Documentation Tab: Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix B – Conceptual Project Data Entry Form B-6 October 5, 2011 Misc. Cost Info. Tab: Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix C CPCE Report Example Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix C – CPCE Report Example C-1 October 5, 2011 Appendix C – CPCE Report Example Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix C – CPCE Report Example C-2 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix C – CPCE Report Example C-3 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix C – CPCE Report Example C-4 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix D CPCE Summary Report Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix D – CPCE Summary Report D-1 October 5, 2011 Appendix D – CPCE Summary Report Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix D – CPCE Summary Report D-2 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix D – CPCE Summary Report D-3 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix E New Sewer Construction Unit Cost Charts • 8 - 36 Pipe / Sod • 42 - 90 Pipe / Sod • 96 - 144 Pipe / Sod • 8 - 36 Pipe / Pavement • 42 - 90 Pipe / Pavement • 96 - 144 Pipe / Pavement Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix E – New Sewer Construction Unit Cost Charts E-1 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix E – New Sewer Construction Unit Cost Charts E-2 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix E – New Sewer Construction Unit Cost Charts E-3 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix E – New Sewer Construction Unit Cost Charts E-4 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix E – New Sewer Construction Unit Cost Charts E-5 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix E – New Sewer Construction Unit Cost Charts E-6 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix F Sewer Rehabilitation Construction Unit Costs Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix F – Sewer Rehabilitation Construction Unit Costs F-1 October 5, 2011 Appendix F – Sewer Rehabilitation Construction Unit Costs Item Unit Unit Cost1,2,3 CIPP Liner – 08-Inch Diameter Linear Foot $32 CIPP Liner – 10-Inch Diameter Linear Foot $39 CIPP Liner – 12-Inch Diameter Linear Foot $55 CIPP Liner – 15-Inch Diameter Linear Foot $66 CIPP Liner – 18-Inch Diameter Linear Foot $77 CIPP Liner – 21-Inch Diameter Linear Foot $83 CIPP Liner – 24-Inch Diameter Linear Foot $88 CIPP Liner – 27-Inch Diameter Linear Foot $99 CIPP Liner – 30-Inch Diameter Linear Foot $121 CIPP Liner – 36-Inch Diameter Linear Foot $165 CIPP Liner – 42-Inch Diameter Linear Foot $220 CIPP Liner – 48-Inch Diameter Linear Foot $352 CIPP Liner – 54-Inch Diameter Linear Foot $5464 CIPP Liner – 60-Inch Diameter Linear Foot $6444 CIPP Liner – 66-Inch Diameter Linear Foot $8204 CIPP Liner – 72-Inch Diameter Linear Foot $9424,5 CIPP Liner – 78-Inch Diameter Linear Foot $1,0914 CIPP Liner – 84-Inch Diameter Linear Foot $1,2984 CIPP Liner – 90-Inch Diameter Linear Foot $1,5054 Point Repair Each $6,0006 Service Connection/Repair Each $2,0007 NOTES: 1. Unless noted otherwise, all unit costs listed include a 1.1 factor to account for ancillary construction costs for aspects such as mobilization, site protection/restoration (minor), and utility relocation (relatively insignificant). 2. All unit costs are representative of the 2011 baseline year (May 2011 ENR CCI = 9035). 3. Unless noted otherwise, all unit costs are based on values in the CIPRO Pay Items tabulations used for preparing current (2011) preliminary cost estimates (see Appendix K). 4. Per MSD experience on previous projects, costs for 54" and larger sewer rehabilitation have been adjusted (31% to 43%) to account for the significant expense of bypass pumping at these sizes; at smaller sizes the cost of bypass pumping is assumed as adequately captured by the aforementioned source of data. 5. No CIPRO value exists. Unit cost shown was determined based on best fit trend line equation developed using CIPP Liner unit costs for all other sizes presented. 6. The Point Repair unit cost is based on the average of the unit costs for “Point Repair-Over 10 Feet Deep” ($6,100) and “Point Repair-Under 10 Feet Deep” ($3,300) contained in the current CIPRO pay items tabulation. This unit cost also includes a 21% ancillary markup for protection and restoration of site, utility relocation, and mobilization. The resultant value was rounded to $6,000/each. 7. The unit cost for Service Connection/Repair is based on bid prices associated with the ongoing annual CIPP lining work being managed by MSD; it is the same value currently used in the preparation of cost estimates for preliminary studies. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix G Storage Facility Construction Unit Cost Curves • Aboveground Storage Facility • Underground Storage Facility Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix G – Storage Facility Construction Unit Cost Curves G-1 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix H Pump Station Facility Construction Cost Curve Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix H – Pump Station Facility Construction Cost Curve H-1 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix I Forcemain Construction Unit Cost Chart (6 thru 48 Forcemain – Sod 6 thru 48 Forcemain – Pavement) Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix I – Forcemain Construction Unit Cost Chart I-1 October 5, 2011 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix J I/I Reduction Unit Costs Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix J – I/I Reduction Unit Costs J-1 October 5, 2011 PUBLIC I/I REDUCTION UNIT COSTS Construction Subcategory: Sewers Item Unit Unit Cost1,2 Cost Basis Cross or Parallel Connection EA $21,000 Note 3 Direct Catch Basin EA $7,000 Note 4 Mainline Defect EA $17,000 Note 5 Construction Subcategory: Manholes Item Unit Unit Cost1,2 Cost Basis6 Mainline Cover – Missing Bolts EA $40 Note 7 Manhole Cover – Pick Holes (no ponding) EA $220 Note 8 Manhole Cover – Pick Holes (ponding) EA $1,650 Note 9 Manhole Frame – Broken Frame EA $700 Note 10 Manhole Frame – Seal/Rim Leak (no ponding) EA $420 Note 11 Manhole Frame – Seal (ponding) EA $2,130 Note 12 Manhole Structure Rehabilitation EA $1,870 Note 13 NOTES (Public I/I Reduction Unit Costs): 1. Unless noted otherwise, all costs include 10% Ancillary Markup for Protection and Restoration of Site, Utility Relocation, and Mobilization. 2. All unit costs are representative of the 2011 baseline year (May 2011 ENR CCI = 9035). 3. Cross or Parallel Connection Cost: Based on analysis of sewers in Upper Deer Creek it was determined that this item could be adequately represented by a simplified composite cost consisting of the following three components: (1) 230 lf of CIPP-lined 12-inch diameter sanitary sewer ($50/lf); (2) 40 lf of CIPP-lined 27- inch diameter storm sewer ($90/lf); and (3) two service lateral connections ($2,000/ea). Unit Cost = 1.1*[(230lf x$50/lf) + (40lf x $90/lf) + (2 x $2,000)] $21,000. 4. Direct Catch Basin Cost: Assume 35 ft repipe of 15-inch storm sewer under sod at a depth of 6 ft; cost (including 21% Ancillary Markup) is $200.72/lf per Sewer Construction Unit Cost Charts in Appendix E. Unit Cost = 35lf*$201/lf $7,000. 5. Mainline Defect Cost: Similar to ‘Cross or Parallel Connection Cost’ with the exception that storm sewer lining is not required. Cost Equation = 1.1 x [(230lf x$50/lf) + (2 x $2,000)] $17,000. 6. Reference in notes to selected CIPRO Pay Items refers to values in the CIPRO Pay Items tabulations used for preparing current (2011) preliminary cost estimates (see Appendix K). 7. Based on cost provided by RJN Group Item ‘Manhole Cover – Missing Bolts’ - $35. Unit Cost = 1.1*$35 $40. 8. Based on CIPRO Pay Item #2573 - ‘Install Manhole Covers’ - $200. Unit Cost = 1.1 x $200 = $220. 9. Based on CIPRO Pay Item #2573 - ‘Install Manhole Covers’ - $200 and CIPRO Pay Item #2444 - ‘Adjust Manhole to Grade’ - $1,300. Unit Cost = 1.1 x ($200 + $1,300) = $1,650. 10. Based on CIPRO Pay Item #2436 - ‘Manhole Frame and Cover Remove and Replace’ - $640. Unit Cost = 1.1 x $640 $700. 11. Based on CIPRO Pay Item #1760 - ‘Manhole Frame Seals’ - $385. Unit Cost = 1.1 x $385 $420. 12. Based on CIPRO Pay Item #2436 - ‘Manhole Frame and Cover Remove and Replace’ - $640 and CIPRO Pay Item #2444 - ‘Adjust Manhole to Grade’ - $1,300. Unit Cost = 1.1 x ($640 + $1,300) = $2,130. 13. Based on average of Hansen Work Orders for MSD Operations ($170/ft) and assumed average manhole depth of 10 ft. Unit Cost = 1.1 x 10ft x $170/ft = $1,870. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix J – I/I Reduction Unit Costs J-2 October 5, 2011 PRIVATE I/I REDUCTION UNIT COSTS Item Unit Unit Cost1,2 Cost Basis3 Downspout EA $2,100 Note 4 Service Lateral EA $9,600 Note 5 Area Drain EA $7,000 Note 6 Driveway Drain EA $8,500 Note 7 Basement Entry Driveway Drain EA $18,000 Note 8 Cleanout EA $850 Note 9 Other EA Varies Note 10 NOTES (Private I/I Reduction Unit Costs): 1. All costs include 21% Ancillary Markup for Protection and Restoration of Site, Utility Relocation, and Mobilization. 2. All unit costs are representative of the 2011 baseline year (May 2011 ENR CCI = 9035). 3. Cited bid tabulations (tabs) and assumptions used to develop unit cost average for all Private I/I Reduction items except ‘Other’ are documented elsewhere. 4. Downspout: Downspout unit cost represents cost of making disconnections at a single parcel. Cost based on assumption that three disconnections are required per parcel and weighted average of three types of downspout disconnections: (1) disconnect to grade ($125 per disconnection, represents 70% of disconnections); (2) disconnect to curb ($700 per disconnection, represents 15% of disconnections); and (3) disconnect to inlet/manhole ($2,500 per disconnection, represents 15% of disconnections). Unit Cost = 1.21 x [($125 x 0.70) + ($700 x 0.15) + ($2,500 x 0.15)] x 3 $700 x 3 $2,100. 5. Service Lateral: Based on bid tab unit cost average ($5,900) for ‘Repair Service Lateral - CIPP (0-50 Linear Feet)’ pay item associated with one MSD I/I reduction projects (3 unique bids), plus $2,000 for the additional service connection repair component. Unit Cost = 1.21 x $7,900 $9,600. 6. Area Drain: Based on bid tab unit cost average ($5,500) for ‘Area Drain: Install/Reroute’ pay item associated with one MSD I/I reduction projects (8 unique bids). Unit Cost = 1.21 x $5,500 $7,000. 7. Driveway Drain: Based on bid tab unit cost average ($7,000) for ‘Driveway Drain: Install/Reroute’ pay item associated with eight MSD I/I reduction projects (22 unique bids). Unit Cost = 1.21 x $7,000 $8,500. 8. Basement Entry Driveway Drain: Multiple bids unavailable; consequently based on CIPRO Pay Item #2653 - ‘Sewer Separation/Driveway Drain Disconnect’ - $15,000 (see Appendix K). Unit Cost = 1.21 x $15,000 $18,000. 9. Cleanout: Based on bid tab unit cost average ($700) for ‘Cleanout: Raise and/or Replace Existing Cover’ pay item associated with six MSD I/I reduction projects (35 unique bids). Unit Cost = 1.21 x $700 $850. 10. Other: Unit cost determined by engineer on case-by-case basis commensurate with the description of I/I reduction item. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix J – I/I Reduction Unit Costs J-3 October 5, 2011 PROJECTED I/I REDUCTION UNIT COST Designation Unit Unit Cost1,2,3,4 Projected I/I Reduction LF $20 NOTES (Projected I/I Reduction Unit Costs): 1. Unit cost includes 21% Ancillary Markup for Protection and Restoration of Site, Utility Relocation, and Mobilization. 2. Unit cost is representative of the 2011 baseline year (May 2011 ENR CCI = 9035). 3. Unit cost is only applicable to areas without an existing I/I investigation or other existing quantification of I/I defects. 4. The unit cost was developed using costs for baseline I/I defect removal for I/I Study Areas with data available in Upper Deer Creek and Gravois Creek Watersheds as of 05/16/2011. This includes 36 of 76 I/I Study Areas in Gravois Creek Watershed and 62 of 75 I/I Study Areas in Upper Deer Creek Watershed. The following five steps were involved: (1) The total length of sanitary sewer within each Study Area based on ArcGIS data was recorded, and the quantity of each type of baseline defect existing within that Study Area based on its precedent I/I investigation was quantified and tabulated. (2) The cost for removal of each identified baseline I/I defect in a Study Area was calculated using the respective public and private I/I reduction unit costs presented previously in this appendix for the various items. (3) The aggregated cost for baseline defect removal in a Study Area was divided by the length of sanitary sewer in that Study Area to develop removal costs on a ‘per linear foot of sanitary sewer’ basis. (4) The values developed in Step (3) were averaged for each of the two watersheds to calculate that watershed’s cost/ft for baseline I/I removal. The resultant averages were $15.19/ft for Deer Creek Watershed and $16.19/ft for Gravois Creek Watershed – a less than 7% variation. (5) Finally, an additional adjustment was made to the costs calculated in Step (4) to account for addressing additional defects identified via CCTV that will typically be incorporated into I/I reduction projects. Based on examination of preliminary study data regarding the additional impact of CCTV repairs to total estimated cost for a typical I/I reduction project, the Projected I/I Reduction unit cost was adjusted to $20/ft of sanitary sewer existing within an area designated for I/I reduction. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix K CIPRO Pay Items Used in Cost Estimating Database Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix K – CIPRO Pay Items Used In Cost Estimating Database K-1 October 5, 2011 Appendix K – CIPRO Pay Items Used in Cost Estimating Database The CIPRO Pay Items tabulated below were used to develop certain costs used in the Cost Estimating Database. The unit costs shown for these Pay Items are those that exist in the current (May 2011) CIPRO Pay Items spreadsheets used for development of preliminary study cost estimates. Unit costs for nearly all CIPRO Pay Items, including those below, have remained relatively flat, i.e., less than 3% change overall change during the past five years. Consequently, as discussed in the body of this BMP, when comparing existing cost estimates for preliminary studies prepared subsequent to 2005 to those developed using the Cost Estimating Database no escalation of the existing estimate is required. Pay Item No. Pay Item Unit Unit Cost 2444 Adjust Manhole To Grade Each $1,300 2467 CIPP Liner - 08 Inch Diameter - 06 MM Linear Feet $29 2700 CIPP Liner - 10 Inch Diameter - 06 MM Linear Feet $35 2699 CIPP Liner - 12 Inch Diameter - 7.5 MM Linear Feet $50 2701 CIPP Liner - 15 Inch Diameter - 07.5 MM Linear Feet $60 2396 CIPP Liner - 18 Inch Diameter - 09 MM Linear Feet $70 2397 CIPP Liner - 21 Inch Diameter - 09 MM Linear Feet $75 2398 CIPP Liner - 24 Inch Diameter - 10.5 MM Linear Feet $80 2399 CIPP Liner - 27 Inch Diameter - 10.5 MM Linear Feet $90 2236 CIPP Liner - 30 Inch Diameter - 13.5 MM Linear Feet $110 2179 CIPP Liner - 36 Inch Diameter - 19.5 MM Linear Feet $150 2201 CIPP Liner - 42 Inch Diameter - 22.5 MM Linear Feet $200 2203 CIPP Liner - 48 Inch Diameter - 24 MM Linear Feet $320 2788 CIPP Liner - 54 Inch Diameter - 24.5 MM Linear Feet $380 2789 CIPP Liner - 60 Inch Diameter - 30 MM Linear Feet $440 2727 CIPP Liner - 66 Inch Diameter - 31.5 MM Linear Feet $570 2479 CIPP Liner - 78 Inch Diameter - 38.5 MM Linear Feet $700 2478 CIPP Liner - 84 Inch Diameter - 43.5 MM Linear Feet $830 2182 CIPP Liner - 90 Inch Diameter - 52.5 MM Linear Feet $960 2573 Install Manhole Covers (Only) Each $200 2436 Manhole Frame And Cover Remove And Replace Each $640 1760 Manhole Frame Seals Each $385 2469 Point Repair - Over 10 Feet Deep Each $6,100 2470 Point Repair - Under 10 Feet Deep Each $3,300 2653 Sewer Separation / Driveway Disconnect Each $15,000 Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual SSOCPD Activity 4 BMP 4 – Cost Estimating October 5, 2011 Appendix L Computations/Assumptions: Construction Costs – Net Present Worth Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix L – Computations/Assumptions: Construction Costs – Net Present Worth L-1 October 5, 2011 Table L1. Summary of Computations Used To Obtain Construction Costs, Project Costs, and Net Present Worth Row Col. 1 2 3 4 5 6 7 8 9 10 11 12 Construction Costs Project Costs Net Present Worth Construction Category (Subcategory in parentheses) Quantities Unit Costs Category Construction Cost Construction Contingency Total Construction Cost (TCC) Additional Project Cost Factor Additional Project Cost Conceptual Project Capital Cost Net Present Worth Factor Net Present Worth (NPW) Conceptual Project Net Present Worth 1 New Sewer Per CPD Form Entries New Sewer Construction Unit Cost Charts BMP 4 Appendix E Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 0.25 Col. 6 x Col. 7 - 1.0 (See Table L2) Col. 6 x Col. 10 - 2 Sewer Rehabilitation Per CPD Form Entries Sewer Rehabilitation Construction Unit Cost Curve BMP 4 Appendix F Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 0.1 Col. 6 x Col. 7 - 1.0 (See Table L2) Col. 6 x Col. 10 - 3 Tunnel Per CPD Form Entries Originator Developed Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 0.25 Col. 6 x Col. 7 - 0.81 (See Table L2) Col. 6 x Col. 10 - 4 Special Feature Per CPD Form Entries Originator Developed Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 0.3 Col. 6 x Col. 7 - 1.0 (Default) (See Table L2) Col. 6 x Col. 10 - 5 Storage Facility Per CPD Form Entries Storage Facility Construction Unit Cost Curves BMP 4 Appendix G Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 0.3 Col. 6 x Col. 7 - *Col. 6 + Line of Best Fit (See Table L2) Col. 6 x 1.036 + $2,185,095 - 6 Pump Station (Facility) Per CPD Form Entries Pump Station Facility Construction Cost Curve BMP 4 Appendix H Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 0.3 Col. 6 x Col. 7 - 1.74 (Default) (See Table L2) Col. 6 x Col. 10 - 7 Pump Station (Forcemain) Per CPD Form Entries Forcemain Construction Unit Cost Chart BMP 4 Appendix I Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 0.3 Col. 6 x Col. 7 - 1.0 (See Table L2) Col. 6 x Col. 10 - 8 Public I/I Reduction (Sewers) Per CPD Form Entries I/I Reduction Unit Costs BMP 4 Appendix J Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 0.15 Col. 6 x Col. 7 - 1.0 (See Table L2) Col. 6 x Col. 10 - 9 Public I/I Reduction (Manholes) Per CPD Form Entries I/I Reduction Unit Costs BMP 4 Appendix J Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 0.15 Col. 6 x Col. 7 - (See Rows 9a through 9c) (Col. 6 x Col. 10) (for respective Rows 9a thru 9c) - .................................................................................................................................. Public I/I Reduction (Manholes) Items for NPW Computation .................................................................................................................................. 9a Manhole Cover – Missing Bolts Pick Holes (No Ponding) Pick Holes (Ponding) MH Cover – Per CPD Form Entry Per CPD Form Entry Per CPD Form Entry Manhole Cover – $ 40 per each $ 220 per each $ 1,650 per each MH Cover Const. Cost: (Col. 2** x Col 3**) **respective items MH Cover: Col. 4 x 0.3 MH Cover: Col. 4 + Col. 5 - - - MH Cover: 2.15 (See Table L2) MH Cover: Col. 6 x Col. 10 - 9b Manhole Frame – Broken Frame Seal/Rim Leak (No Ponding) Seal (Ponding) Manhole Frame – Per CPD Form Entry Per CPD Form Entry Per CPD Form Entry Manhole Frame – $ 700 per each $ 420 per each $ 2,130 per each MH Frame Const. Cost: (Col. 2** x Col 3**) **respective items MH Frame: Col. 4 x 0.3 MH Frame: Col. 4 + Col. 5 - - - MH Frame: 1.0 (See Table L2) MH Frame: Col. 6 x Col. 10 - 9c Manhole Structure Rehabilitation Per CPD Form Entry $1,870 per each MH Structure Rehab Const. Cost: Col. 2 x Col 3 MH Structure Rehab: Col. 4 x 0.3 MH Structure Rehab: Col. 4 + Col. 5 - - - MH Structure Rehab: 3.53 (See Table L2) MH Structure Rehab: Col. 6 x Col. 10 - .................................................................................................................................. Public I/I Reduction (Manholes) Items for NPW Computation .................................................................................................................................. 10 Private I/I Reduction Per CPD Form Entries I/I Reduction Unit Costs BMP 4 Appendix J Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 - $2,000 x # of defects - 1.0 (See Table L2) Col. 6 x Col. 10 - 11 Projected I/I Reduction** Per CPD Form Entries I/I Reduction Unit Costs BMP 4 Appendix J Col. 2 x Col 3 Col. 4 x 0.3 Col. 4 + Col. 5 0.20 Col. 6 x Col. 7 - 1.0 (See Table L2) Col. 6 x Col. 10 - 12 - Total Cost for Environmental Mitigation / Excessive Utility Conflict / Land Acquisition per CPD Form Entry - - - - Col. 3 - - - 13 TOTALS - - Rows 1 thru 11 Rows 1 thru 11 Rows 1 thru 11 - Rows 1 thru 12 Col. 6 + Col. 8 - Rows 1 thru 11 Col. 8 + Col. 11 *Equation used in lieu of Net Present Worth Factor **Not an actual construction category, although it functions as one for the determination of costs. Metropolitan St. Louis Sewer District SSO Control Plan Development Best Management Practices Manual BMP 4 – Cost Estimating Appendix L – Computations/Assumptions: Construction Costs – Net Present Worth L-2 October 5, 2011 Table L2. Basis for Net Present Worth Factors Life Cycle Assumptions (Note 1) Net Present Worth Factor Components Construction Category (Subcategory in parentheses) Annual O&M Expenses Periodic Replacement Expenses Salvage Construction O&M Replacement Salvage Net Present Worth Factor (Note 2) New Sewer None None None 1.0 0.0 0.0 0.0 1.0 Sewer Rehabilitation None None None 1.0 0.0 0.0 0.0 1.0 Tunnel None None Note 3 1.0 0.0 0.0 -(0.5) x 0.3823 = -0.19 0.81 Special Feature Note 4 Note 4 Note 4 1.0 Note 4 Note 4 Note 4 Note 4 Storage Facility Note 5 Note 6 None 1.0 3 MG: $46,500 x 31.81 6 MG: $49,080 x 31.81 10 MG: $50,500 x 31.81 3 MG: ($15,000 x 5.74) + ($550,000 x 1.73) 6 MG: ($20,000 x 5.74) + ($645,000 x 1.73) 10 MG: ($30,000 x 5.74) + ($775,000 x 1.73) 0.0 0.0 0.0 TCC + Line of Best Fit (Note 7) Pump Station (Facility) Note 8 Note 9 None 1.0 0.0146 x 31.81 = 0.46 (0.0308 x 4.24) + (0.0462 x 2.53) + (0.0492 x 0.62) = 0.28 0.0 1.74 (Note 10) Pump Station (Forcemain) None None None 1.0 0.0 0.0 0.0 1.0 Public I/I Reduction (Sewers) None None None 1.0 0.0 0.0 0.0 1.0 Public I/I Reduction (Manholes) None Note 11 None 1.0 0.0 Cover = 0.2 x 5.74 = 1.15 / Frame = 0.0 / Structure = 2.53 0.0 2.15 / 1.0 / 3.53 Private I/I Reduction None None None 1.0 0.0 0.0 0.0 1.0 Projected I/I Reduction None None None 1.0 0.0 0.0 0.0 1.0 NOTES: 1. General Life Cycle Assumptions: • Planning Period = 50 years Inflation Rate = 3.0% Interest Rate = 5.0% Real Interest Rate = i = 1.94% • Credits are shown as negative numbers. For simplification, elimination of O&M costs and replacement costs attributable to the abandonment or demolition of an existing asset is ignored, and is partially offset by ‘0.0’ O&M expenses for many categories. • New sewers, sewer rehabilitation, pump station forcemains, and I/I reduction measures associated with sewers are assumed to have a design life of 50 years and minimal O&M expenses. Consequently, the associated Net Present Worth (NPW) Factor is assumed as 1.0, i.e., identical to the Total Construction Cost for the category or subcategory. The District is not responsible for O&M or replacement costs associated with Private I/I Reduction measures, so the NPW Factor for this category is also 1.0. • Additional life cycle assumptions applicable to specific construction categories are discussed in Notes 3 through 5 and 7 through 9 below. 2. The Net Present Worth (NPW) Factor is the sum of the respective Construction, O&M, Replacement, and Salvage component factors for the Construction Category. 3. Tunnels are assumed to have an asset life of 100 years. Assuming straight line depreciation, at the end of the 50-year planning period it will have a salvage value equal to one half (0.5) of its initial construction cost. To convert this ‘Year 50’ amount to ‘Year 0’ costs, it is multiplied by a Single Payment Present Worth Factor (SPPWF). For ‘i’ = 1.94% and ‘n’ (number of years) = 50, SPPWF = (1 + i)-n = 0.38. 4. Due to the nature of the construction category, the NPW Factor for Special Feature entries is determined on a case-by-case basis. The Cost Estimating Database default value of 1.0 should be adjusted as necessary by entering the desired factor in lieu of the default value at the Special Feature ‘NPW Factor’ field on the Data Entry Form. For additional guidance or resources in situations that may warrant adjustment of the NPW Factor contact the Section Manager. 5. Based on MSD Operations detailed budget estimates for currently planned mid-size storage facilities, annual O&M costs for a mid-size (6 million gallon (MG) storage facility are $49,080; to enable creation of a trend line, engineering judgment was used to adjust these costs for smaller (3 MG) and larger (10 MG) storage facilities. To convert these annual costs during ‘Year 1’ through ‘Year 50’ to ‘Year 0’ costs, the annual O&M cost is multiplied by a Uniform Series Present Worth Factor (USPWF). For ‘i’ = 1.94% and ‘n’ = 50, USPWF = [(1 + i)n – 1] ÷ [i x (1 + i)n] = 31.81. 6. Based on MSD Operations detailed budget estimates for currently planned mid-size storage facilities, odor control media is replaced every five years at a cost of approximately $20,000 and pumps, gates, and odor control equipment are replaced every 15 years at a cost of approximately $645,000. To enable creation of a trend line, engineering judgment was used to adjust these costs for smaller (3 million gallon (MG)) and larger (10 MG) storage facilities. To convert these periodic replacement costs to ‘Year 0’ costs, each discrete replacement cost is multiplied by the appropriate SPPWF. For ‘i’ = 1.94% and replacements at ‘n’ = 5, 10, 15, 20, 25, 30, 35, 40, and 45, the ‘cumulative’ SPPWF is 5.74 (i.e., 0.9083 + 0.8250 + 0.7494 + 0.6807 + 0.6183 + 0.5616 + 0.5101 + 0.4634 + 0.4209). For ‘i’ = 1.94% and replacements at ‘n’ = 15, 30, and 45, the ‘cumulative’ SPPWF is 1.73 (i.e., 0.7494 + 0.5616 + 0.4209). 7. Net present worth values exclusive of the construction cost component (ordinate) for 3 MG, 6 MG, and 10 MG sizes were plotted versus respective Total Construction Costs (abscissa) at these three sizes. The resultant line of best fit (y = 0.036x + $2,185,095) is used to calculate the amount of net present worth contribution associated with O&M and replacement for any size of facility. This calculated amount is added to the Total Construction Cost to determine Net Present Worth. 8. Based on MSD Operations records and estimates for small and medium pump stations (peak design flowrate less than 1.7 mgd), annual O&M costs (including power) are approximately $9,500 (1.46% of Total Construction Cost). To convert these annual costs during ‘Year 1’ through ‘Year 50’ to ‘Year 0’ costs, the annual O&M cost is multiplied by a Uniform Series Present Worth Factor (USPWF). For ‘i’ = 1.94% and ‘n’ = 50, USPWF = 31.81. 9. Based on MSD Operations records and estimates for small- and medium-sized pump stations, pumps are replaced every seven years at a cost of approximately $20,000 (3.08% of Total Construction Cost), electrical items and controls are replaced every ten years at a cost of approximately $30,000 (4.62% of Total Construction Cost), and selected piping and structural features are replaced or refurbished every 25 years at a cost of approximately $32,000 (4.92% of Total Construction Cost). To convert these periodic replacement costs to ‘Year 0’ costs, each discrete replacement cost is multiplied by the appropriate SPPWF. For ‘i’ = 1.94% and replacements at ‘n’ = 7, 14, 21, 28, 35, 42, and 49, the ‘cumulative’ SPPWF is 4.24 (i.e., 0.8740 + 0.7640 + 0.6677 + 0.5836 + 0.5101 + 0.4459 + 0.3897). For ‘i’ = 1.94% and replacements at ‘n’ = 10, 20, 30, and 40, the ‘cumulative’ SPPWF is 2.53 (i.e., 0.8250 + 0.6807 + 0.5616 + 0.4634). For ‘i’ = 1.94% and replacement at ‘n’ = 25, the SPPWF is 0.62. 10. For large pump stations (peak design flowrate greater than 1.7 mgd), the resultant Net Present Worth using this factor should be examined, and adjusted on a case-by-case basis if necessary. Adjustments can be made by entering the desired factor in lieu of the default value of 1.74 at the Pump Station Facility ‘NPW Factor’ field on the Data Entry Form. For additional guidance or resources in situations that may warrant adjustment of the NPW Factor contact the Section Manager. 11. To maintain I/I reduction benefits achieved by addressing manhole defects, periodic inspection and refurbishment of certain components are required. Specifically 20% of repaired manhole cover items require refurbishment every 5 years and all rehabilitated manhole structures require additional repair every 10 years; no periodic replacement expenses are associated with repaired manhole frames. Due to the itemized nature of this construction category and the diverse nature of replacement expenses, the Cost Estimating Database drills down to the individual I/I reduction items as illustrated in Table L1 to determine the Net Present Worth for the Public I/I Reduction (Manholes) subcategory. As documented in Note 5, for ‘i’ = 1.94% and replacements at ‘n’ = 5, 10, 15, 20, 25, 30, 35, 40, and 45, the ‘cumulative’ SPPWF is 5.74; per Note 8, for ‘i’ = 1.94% and replacements at ‘n’ = 10, 20, 30, and 40, the ‘cumulative’ SPPWF is 2.53.