Technical Memorandum Cost Criteria for 2010 System Capacity Plan

Transcription

1 2010 SASD SEWER SYSTEM CAPACITY PLAN UPDATE Technical Memorandum Cost Criteria for 2010 System Capacity Plan PREPARED BY: My Huynh DATE: September 13, 2011 REVIEWED BY: Sonny Lunde INTRODUCTION This Technical Memorandum presents the methodology used to develop estimated costs for project shed areas proposed in the Sacramento Area Sewer District System Capacity Plan The estimated costs may then be incorporated into SASD s rate and fee study. 1. DEVELOPMENT OF ESTIMATED COST Estimates of the capital costs associated with the proposed project areas are order of magnitude estimates. An order of magnitude estimate is one that is made without detailed engineering data, and uses techniques such as cost curves and scaling factors from similar projects. The overall expected level of accuracy of the cost estimates is approximately 30%. All costs presented in this memorandum have been adjusted to an Engineering News Record construction cost index of 9527, which represents the average of the January 2011 ENR cost indexes for the San Francisco area (10116) and the 20-Cities ENR average (8938). The estimated costs were developed using a baseline pipe construction cost with added cost and markups for related items. An example cost estimate sheet for a hypothetical project is presented in Figure 1. Figure 1 Cost Estimate Sheet Example Baseline Pipe Construction Costs + Additional Costs for Geotechnical Factors + Additional Costs Traffic Control + + Additional Costs for Productivity Factors Surface Restoration Costs + Costs for Special Structures and Pump Stations = Subtotal + 5% Mobilization/Demobilization = Estimated Construction Cost Subtotal + 30% Contingencies for Unknown Conditions = ESTIMATED CONSTRUCTION COST + Right-of-Way/Easement Acquisition + 25% Engineering, Administration, and Legal Cost = TOTAL PROJECT COST 2010 SCP Tech Memo - 7 Cost - Final.Docx Page 1 of 18 November 29, 2011

2 2. SUMMARY OF ESTIMATED UNIT COST For easy reference, a summary of estimated unit cost is included in Table 1. Table 1 Summary of Estimated Unit Cost Item Baseline Construction Open Cut Gravity Sewer Open Cut DIP Force Main Trenchless Pipe Construction Geotechnical Factors Description 8 to 42-inch diameter, 8 to 28 feet deep 4 to 18-inch diameter, 4 to 16 feet deep Bore and Jack, Microtunnel, Pipe Ramming. With and without casing Unit Cost Range $160 to $680/lf $140 to $430/lf $305 to $1,700/lf Section Reference Additional Dewater Deep well system $45 to $60/lf Additional Sheeting and Shoring Cobble Areas Hard Rock Areas Traffic Control Additional Traffic Control Productivity Factors Congested Traffic/Utility Corridor Remove and Replace Delay Factor Trench boxes, solid shoring, and sheet piles $30 to $710/lf Developed Areas Undeveloped Areas Northeastern part of service area For pipe alignments along major roads with four or more lanes of traffic. For pipe alignments along major roads with four or more lanes of traffic. For pipe alignments to be upsized in place. 100% of baseline cost 20% of baseline cost 100% of baseline cost $45/lf % of baseline cost 25% of baseline cost SCP Tech Memo - 7 Cost - Final.Docx Page 2 of 18 November 29, 2011

3 Table 1 Summary of Estimated Unit Cost - Continued Item Surface Restoration Pavement Restoration Landscape Restoration Revegetation Creek Restoration Sewer Structures Junction Structures Pump Stations Description Final Paving and patch paving 15 feet width Replanting in medians and landscaped area 40 feet width Hydroseeding in open areas 80 feet width Replanting and minor bank erosion control 40 feet width Junction, transition, and turning structure 10 MGD or less firm capacity Based on low, medium, and high total dynamic heads. Unit Cost Range Section Reference $100/lf $3.00/sf $0.25/sf $12/sf $25,000 to $850,000 per structure $0.5 to $6.1M Mobilization/Demobilization % of subtotal 5% 3.7 Contingencies % of Estimated Construction Cost Subtotal 30% 3.8 Easement Acquisition Acquisition Cost Easements in Newly Constructed Development Temporary Construction Easements Title reports, appraisals, real estate staff time Granted to SASD as condition of development $7,000 per parcel No Cost to SASD 80 feet width $0.80/sf 3.9 Permanent Easement 20 feet width $4.00/sf 3.9 Engineering, Administration, and Legal Costs % of Estimated Construction Cost 25% SCP Tech Memo - 7 Cost - Final.Docx Page 3 of 18 November 29, 2011

4 3. BASIS OF ESTIMATED COST Construction costs include costs for installation of gravity pipelines, force mains, and pump stations. The basis for these costs is described below. 3.1 Baseline Pipeline Construction Baseline pipeline construction costs were developed for open cut gravity sewer trunks, force mains, and trenchless pipe construction. These costs are based on a combination of construction bids for projects in Sacramento and other urban areas in California, catalog unit price costing, and adjustments to unit costs identified in previous SASD Master Plans (2000 and 2006). Both the baseline gravity pipe and force main construction costs include the following: Vertical trench walls to reduce utility conflicts Trench box or hydraulic shores Select, imported backfill in the pipe zone and native back fill above the pipe zone to the pavement structural base. It is assumed that the spoil may be hauled to a local disposal site. Backfill would be compacted to 90 percent to within 2 feet of the ground surface. Temporary pavement to be placed over excavated areas in traveled roads at the end of each day. Sump pump in the trench used for minor dewatering. Minor traffic control including two way flagging, construction area traffic signs, and channelizers Open Cut Gravity Sewers Baseline unit pipe construction costs were developed for gravity collector and trunk sewers ranging from 8 to 42 inches in diameter for four depth-to-invert ranges: 8 to 16 feet, 16 to 20 feet, 20 to 24 feet, and 24 to 28 feet. These unit costs are presented in Table 2. It was assumed that gravity trunk sewers installed by open-cut construction would not be constructed deeper than 28 feet deep. In addition to the baseline gravity pipe and force main cost assumptions, the baseline gravity vcp pipe construction costs include the following assumptions: Pipe material: VCP for 8 to 36-inch sewers; and PVC-lined (or calcareous aggregate) RCP for 39-inch and larger sewers. Manholes will be located every 400 feet in collector pipes (working pipe capacity of less than 1 mgd, typically pipes 8-inch to 10-inch) and every 500 feet in trunk sewers (working pipe capacity of 1 mgd or greater, typically pipes 10-inch or greater). Trench dams if needed to prevent migration of groundwater along the trench section and/or filter fabric to prevent migration of soil or intermediate back fill into the pipe zone. Collector sewer not to exceed 19 feet in depth SCP Tech Memo - 7 Cost - Final.Docx Page 4 of 18 November 29, 2011

5 Table 2 Open Cut Gravity Pipe Unit Cost Pipe Size (in) Vitrified Clay Pipe 8 to 16 feet depth Open Cut Gravity Pipe Installation Cost ($/lf) 16 to 20 feet depth 20 to 24 feet depth 24 to 28 feet depth Reinforced Concrete Pipe Open Cut Ductile Iron Force Main Unit baseline pipe construction costs for force mains are presented in Table 3. In addition to the baseline gravity pipe and force main cost assumptions, the baseline force main construction costs include the following assumptions: A minimum of 4 feet of cover above the pipe. Pipe material: Ductile iron pipe. Air release valves, vacuum release valves, or combination valves located every 3,000 feet in 60-inch diameter manholes. Trench dams installed at 100 feet spacing in areas with high groundwater along the trench section and installation of filter fabric to prevent migration of soil or intermediate back fill in the pipe zone. Includes trust blocks SCP Tech Memo - 7 Cost - Final.Docx Page 5 of 18 November 29, 2011

6 Table 3 Open Cut DIP Force Main Unit Cost Force Main Size (in) Less Than 10 Feet Deep Cost ($/lf) 10 to 16 Feet Deep Cost ($/lf) Trenchless Pipe Construction Trenchless pipe construction is an advantageous pipe method to install pipelines that minimizes impacts to the public and the restoration. For this System Capacity Plan, baseline pipe construction costs were also developed for microctunneling, bore and jack, and pipe ramming. Although pipe bursting is often a viable method for installing and upsizing pipes, its dependency on local utility location information and pipe condition makes it difficult to consider on a planning level document. The same goes for horizontal directional drilling, with its high sensitivity to geological conditions. For this reason, SASD has chosen not to include pipe bursting and horizontal directional drilling as one of its trenchless methods in the System Capacity Plan, but considerations for use can be evaluated during the Project Development Phase. The following assumptions were made regarding trenchless pipe construction: All highway and railroad crossing will require a casing. All major roads (4 lanes or more) will require a trenchless crossing. All creek crossing will be constructed using open cut methods (see creek restoration costs in later section). Neither mircrotunneling nor bore and jack construction methods will be used in cobble areas (see section on cobble and hard rock construction for definition of cobble area) Pipe ramming will be used for required trenchless crossings in cobble areas. Pipe ramming requires a steel casing. Bore and jack equipment for 59-inch diameters and smaller is typically auger boring equipment. Auger boring is not accurate enough for gravity sewer installation. Auger boring can be used to install casings for force mains. Casing is determined by the outside diameter of the carrier pipe bell plus 24 inches with a minimum size of 36-inches. Bore and jack equipment for 60-inch diameters and larger is typically open shield equipment (laser target used to steer). Open shield equipment is accurate enough for gravity sewer installation. Except for microtunneling, unit pricing includes mobilization/demobilization, bore, casing (if specified), and pipe. Microtunneling includes all of the previous items except for mobilization/demobilization. For 2010 SCP Tech Memo - 7 Cost - Final.Docx Page 6 of 18 November 29, 2011

7 Microtunneling mobilization/demobilization, bore holes less than 24-inches will cost $110,000; bore holes 24 to 48-inches will cost $180,000; and bore holes 48 to 72-inches will cost $260, Trenchless Construction Cost The recommended unit costs for trenchless pipe construction are the following: Table 4 Trenchless Pipe Construction Unit Cost Pipe Size (in) Direct Jack (No Casing) Microtunneling* ($/lf) Casing Size (in) Casing Required Microtunneling* ($/lf) Bore and Jack ($/lf) Casing Size (in) Cobble Area Pipe Ramming ($/lf) * Unit pricing for microtunneling does not include mobilization and demobilization. Use the following for microtunnel mobilization and demobilization cost: Bore holes less than 24-inches $110,000, Bore holes 24 to 48-inches $180,000, Bore holes greater than 48-inches $260, Jacking and Receiving Pits The construction for microtunneling, boring and jacking, and pipe ramming pipeline installation also includes costs associated with the jacking and receiving pits. If a long length of microtunneling is required, then a series of drives with the associated pits will be used. The maximum drive lengths of the boring or tunneling machines are shown in Table 5. These drive length are conservative and will work for most areas of Sacramento County. The recommended costs for jacking and receiving pits are shown in Table SCP Tech Memo - 7 Cost - Final.Docx Page 7 of 18 November 29, 2011

8 Table 5 Maximum Drive Lengths Pipe Diameter (in) Drive Length (ft) Microtunneling 8 to 10-inch 1, to 24-inch to 33-inch inch and larger 150 Pipe Ramming All Diameters 300 Table 6 Jacking and Receiving Pit Cost Pipe Invert Depth Pit Cost 16 feet or less Jacking Pit $80,000 Receiving Pit $25,000 Greater than 16 feet Jacking Pit $115,000 Receiving Pit $40, Geotechnical Factors Depending on location and site conditions, pipeline construction may require additional costs associated with geotechnical factors. These additional costs include increased dewatering, additional sheeting and shoring, and special equipment or methods associated with construction in difficult soil conditions such as cobbles or rock Additional Dewater The baseline pipeline costs include the cost of sump pump in the trench for minor dewatering. Some areas of Sacramento County require a more aggressive dewatering scheme. The cost of installation and maintenance of each dewatering well could range from $1,000 to $5000. The range of costs depends on depth of wells, the need for sand screens, and the proximity of electrical services for the pump motors. The cost of dewatering also depends upon the spacing of the dewatering wells. To adequately dewater a trench with high groundwater, dewatering wells are generally located at least 50 to 75 feet apart. If the soils have large amounts of clay or other materials which decrease the capability to dewater the soils, wells are frequently spaced 50 feet apart. For the purposes of this System Capacity Plan, it is assumed that the wells would be spaced 50 feet apart. Therefore, the unit dewatering cost could range from $20 to $100 per foot. Dewatering cost will be applied in areas of the County with known high groundwater as shown Figure SCP Tech Memo - 7 Cost - Final.Docx Page 8 of 18 November 29, 2011

9 Figure 2 High Groundwater Areas For the purpose of this System Capacity Plan, dewatering cost from Table 7 will be applied in areas of the County with known high groundwater as shown in Figure 2. Table 7 Additional Dewatering Unit Cost Groundwater Infiltration Additional Dewatering Cost 200 GPD/Acre $45/LF of pipe 500 GPD/Acre $60/LF of pipe All Other Areas $0 Minor dewatering included in the cost of the pipe installation Additional Sheeting and Shoring Sheeting and shoring methods could range from hydraulic shores to interlocking full-sheets. The specific type of shoring used will depend upon trench depths, soil conditions, and groundwater levels. For the purposes of determining sheeting and shoring requirements for this System Capacity Plan, three different ground conditions will be used: no groundwater, undeveloped areas with high groundwater, and developed areas with high 2010 SCP Tech Memo - 7 Cost - Final.Docx Page 9 of 18 November 29, 2011

10 groundwater. For pipeline constructed in areas without high groundwater, it is assumed that hydraulic shores or trench boxes will be used. This cost is included in the baseline pipe construction cost. The recommended sheeting and shoring costs for the three conditions and various pipeline depths are presented in Table 8. The cost of the solid shoring ranges from $1 to $3 per square foot. The cost of the sheet piles ranges from $20 to $40 per square foot. These costs have been used to also assume that any excavation deeper than 8 feet in areas of high groundwater area of the County, where the subsurface profile typically consists of 10 feet of clay over clean sands. Therefore, additional dewatering costs will also be required for open cut construction in areas of high groundwater (except where sheet piles are used), as indicated in Table 8. Table 8 Shoring and Dewater Unit Cost for Various Groundwater Conditions Depth to Invert (ft) No Groundwater High Groundwater Undeveloped Area High Groundwater Developed Area 8 to 16 Baseline (no additional cost) Partially laid back trench with trench box and dewatering wells. $30/LF + dewatering Solid shoring and dewatering wells. $75/LF + dewatering 16 to 20 Baseline (no additional cost) Partially laid back trench with trench box and dewatering wells. $60/LF + dewatering Solid shoring and dewatering wells. $110/LF + dewatering 20 to 24 Baseline (no additional cost) Partially laid back trench with trench box and dewatering wells. $90/LF + dewatering Solid shoring and dewatering wells Shoring: $135/LF $135/LF + dewatering 24 to 28 Baseline (no additional cost) Partially laid back trench with trench box and dewatering wells. $120/LF + dewatering Interlocking sheet piles $710/LF Ground Condition Large portions of Sacramento County have a significant amount of cobbles in the soil. These cobbles, which originated from the Sierra Nevada Mountains and were carried and deposited in the Sacramento area by the American River, are rounded and very hard. For this reason, the cobbles can be problematic when constructing a pipeline. Therefore a cobble construction factor will be added to the portions of the projects in extra processing of excavated material necessary to produce acceptable backfill, and shoring difficulties. For projects that will be constructed before the road and utility improvement are built, the challenges are not as great as the projects that are built after the road and utility improvements have been constructed. For this System Capacity Plan, the cobble construction factor will be applied within the areas shown in Figure 3. Cobble issues reduce in magnitude from the northeast to southwest in this area. For this reason, projects located on Gerber Road will have zero cobble factor and projects located on Florin Road will have 50% cobble factor instead of the 100% cobble factor. In the northeast corner of the SASD service area, there is hard rock located in the trench zone. This hard rock significantly reduces construction productivity and adds considerable cost to pipeline projects. For this System Capacity Plan, the hard rock construction factor will be applied to all projects located in the areas shown in Figure SCP Tech Memo - 7 Cost - Final.Docx Page 10 of 18 November 29, 2011

11 Figure 3 Hard Rock and Cobble Construction Factor Areas For the System Capacity Plan, use the following as construction factors: Cobble Construction Factor: Developed Areas: 100% of Baseline Pipe Construction Costs Undeveloped Areas: 20% of Baseline Pipe Construction Costs Note: Areas within the cobble area but south of Elder Creek Road, reduce the cobble construction factor by 50%. Hard Rock Construction Factor: 100% of Baseline Pipe Construction Costs 2010 SCP Tech Memo - 7 Cost - Final.Docx Page 11 of 18 November 29, 2011

12 3.3 Traffic Control Minor traffic control consisting of two-way flagging, construction area signs, traffic cones, and channelizers are included in the pipe installation cost. For roads identified as having 4 or more lanes, additional traffic control will be needed. Additional traffic control includes the cost of traffic design and use of flagging, construction area traffic signs, temporary crash cushions, barricades, channelizes, flashing beacons, K-rails, and changeable message boards. Traffic control on major roads could range $3000 to $6000 per day. If it is assumed that construction will proceed at a rate of 100 feet/day, the equivalent cost would be $30 to $60 per foot. For this System Capacity Plan, the following unit cost will be used: Increased Traffic Control: $45 per linear foot of alignment located in major roads (4 or more lanes). 3.4 Productivity Factors Traffic/Utility Corridor Delay Factor Constructing a pipeline in a busy road or a road with numerous utilities is slower (and therefore more costly) than constructing a pipeline in a quiet residential or rural street. Often times, there are restricted work areas and hours to maintain safe traffic flow, driveway access coordination, and utility conflicts. Therefore a congested traffic/utility corridor delay factor reflecting the loss of productivity will be added to alignments on roads with 4 or more lanes. Congested Traffic/Utility Corridor Delay Factor: 15% of baseline pipe construction costs in major roads (4 or more lanes) Remove and Replace Delay Factor Constructing a new pipeline in an alignment that requires the removal of the existing gravity sewer is more costly than constructing a pipeline in a new alignment. The additional cost is caused by the necessary bypass pumping and the extra processing of the excavated material to remove the broken pipe from the backfill material. However, contractors are very creative and could typically avoid completely removing the pipe or remove it at a lower cost than traditional means. For those reasons, the remove and replace delay factor will be the following: Remove and Replace Delay Factor: 25% of baseline pipe construction costs SCP Tech Memo - 7 Cost - Final.Docx Page 12 of 18 November 29, 2011

13 3.5 Surface Restoration Surface restoration includes replacement of pavement for pipeline alignments in paved roadways and replacement of landscaping or other vegetation for pipelines constructed in easements or across open land Pavement Restoration To ensure that the pipe trench does not affect the integrity of the road, restoration will be made to the road structural section above the pipe trench and overlayed. A tee trench will include a 6-inch thick asphalt concrete pavement over 6-inches of 3/4 inch aggregate base compacted to 95 percent. The asphalt concrete section will extend beyond the trench walls by 12 inches. On both sides of the 6-inch thick pavement, a strip of 2-inch deep grinding and new pavement overlay the road. The grinding and pavement will extend to lip of gutter, lane line, or center of traffic lane. To determine the cost of pavement restoration, two factors must be determined: width and unit cost, While the width of pavement restoration does vary with pipe diameter, the width is more strongly influenced by factors such as proximity to edge of pavement, raveling of trench wall, and strength of existing pavement. These factors are hard to determine during the planning stage; therefore, for the System Capacity Plan, a pavement restoration width of 15 feet (12 foot traffic lane with a 3 foot shoulder) and a pipe trench accommodating an 18- inch pipe (42-inch wide trench), will be used. For the purposes of this Master Plan, an average cost over the entire 15 foot width will be used, as follows: Pavement Restoration Cost (15 feet width): $100 per linear foot Other Restoration All trunk sewers and constructed outside of paved roadways and temporary lay down areas, if not constructed by a developer as part of a subdivision, will require either revegetation or landscape restoration. Open cut creek crossings will require creek restoration. Revegetation, also referred to hydroseeding, is used to restore pipeline routes located in open fields. Landscape restoration is used when the alignment is located in the landscaped medians or other landscaped areas. For new subdivisions, pipelines are usually constructed prior to constructing the subdivision. For this reason revegetation and landscape restoration cost will be included as part of a new subdivision cost and not part of the capital funding projection. Where required, both landscape restoration and revegetation will be applied to the entire area disturbed by the construction operation. Typically, the disturbed area is larger when the alignment goes through an open field than when the alignment goes through a creek or an area with landscape improvements. For this reason, for this System Capacity Plan, the revegetation width will be assume to be 80 feet, and the creek and landscape restoration widths will be 40 feet. The following costs shall be used: Landscape Restoration (replanting in medians or landscaped areas, 40 feet wide): $4.00 per square foot Revegetation (hydroseeding in open areas, 80 feet wide): $0.25 per square foot Creek Restorations (replanting, minor bank erosion control, 40 feet wide): $12.00 per square foot 2010 SCP Tech Memo - 7 Cost - Final.Docx Page 13 of 18 November 29, 2011

14 3.6 Sewer Structures Junction Structures Junction structures are use to combine flows coming from different pipes into one out flowing pipe. They are required at the connection points of trunk sewers to interceptors. If the trunk sewer is being connected to an existing or previously constructed interceptor, then the cost for this junction structure will be included in the trunk sewer cost estimate. If the junction structure is constructed at the time of the interceptor construction, then it will be assumed to be included in the interceptor cost estimate and not included in the SASD trunk sewer construction cost. Transition structures and turning structures are similar to junction structures in construction methods and cost but differ in not combining flows. For this System Capacity Plan, transition and turning structures will be costed like junction structures using Table 9. Table 9 Junction Structure Cost Junction Structure Cost Trunk Sewer Junction Structure Less than 24-inch Diameter Outlet Pipe $25, to 36-inch Diameter Outlet Pipe $50,000 Interceptor/Trunk Junction Structure 60-inch or less diameter Interceptor $165, to 78-inch Diameter Interceptor $230, to 144-inch Diameter Interceptor $850, Pump Stations Pump stations are used to convey wastewater using pressurized pipelines. Costs can vary greatly depending on how much wastewater is being conveyed an on how far the wastewater will be pumped. Typically pump stations of the same firm capacity used to raise the hydraulic grade line (lift stations) require smaller pumps and appurtenances than pump stations used to convey wastewater from one location to another and are therefore less costly. The total dynamic head of pump station is a factor for determining the pump size, motor control center size, switch board size, wet well size, as well as other appurtenances. For those reasons, the pump stations cost shown in Table 10 are base on three different scenarios representing low, medium, and high head pump stations SCP Tech Memo - 7 Cost - Final.Docx Page 14 of 18 November 29, 2011

15 Table 10 Pump Station Cost Pump Station Firm Capacity Pump Station Cost Based on Total Dynamic Head Low Head Less than 60 feet Medium Head 60 to 120 feet High Head Greater than 120 feet Less than 1 MGD $560,000 $680,000 $850,000 1 MGD to 2 MGD $810,000 $980,000 $1,200,000 2 MGD to 3 MGD $1,200,000 $1,400,000 $1,800,000 3 MGD to 4 MGD $1,700,000 $2,000,000 $2,400,000 4 MGD to 5 MGD $2,100,000 $2,400,000 $2,900,000 5 MGD to 6 MGD $2,700,000 $3,000,000 $3,700,000 6 MGD to 7 MGD $3,100,000 $3,500,000 $4,200,000 7 MGD to 8 MGD $3,800,000 $4,300,000 $5,100,000 8 MGD to 9 MGD $4,200,000 $4,700,000 $5,600,000 9 MGD to 10 MGD $4,700,000 $5,100,000 $6,100,000 Often times, pump stations are upgraded to increase the pumping and storing capacity. For increasing the capacity of an existing station, use the following cost factors: Table 11 Rehab Pump Station Cost Factor Pump Station Capacity Increase Percentage Cost of New Capacity Pump Station Less than 0.5 MGD 25% 0.5 to 2 MGD 50% 2 MGD to 4 MGD 75% Greater than 4 MGD 100% 3.7 Mobilization and Demobilization These costs usually generally cover contractor activities when the contractor initially moves construction facilities and equipment to the project site and at the end of the project when removing facilities and equipment from the site. These costs also include temporary construction needed to begin the project (access roads, power, internet, etc.). Typically language in SASD construction contracts limit mobilization and demobilization bid cost to approximately 5 percent to prevent spending an unreasonably large portion of the construction cost prior to construction SCP Tech Memo - 7 Cost - Final.Docx Page 15 of 18 November 29, 2011

16 Mobilization/Demobilization: 5% of the Construction Cost Subtotal 3.8 Contingencies This contingency is used to adjust the Estimated Construction Cost Subtotal such that the total cost will account for unforeseen economic variables that are difficult to quantify or cover portions of work that were not estimated. The percentage used for an overall project will vary depending upon level of effort at various stages of the project. The percentage used is adjusted based upon detailed or lack of detailed geotechnical, utility, and other project details and information. Due to a lack of detailed information during the planning phase, a contingency factor of 30 percent is considered appropriate for planning level costs. Contingencies for Unknown Conditions: 30% of the Estimated Construction Cost Subtotal. 3.9 Easement Acquisition The acquisition of easements can vary in cost depending on the incidentals (title reports, appraisals, etc.) and cooperation of the property owners. On average, the cost of acquiring an easement is $7000 per parcel and do not include the price of the easement. Because higher cost construction projects do not necessarily yield proportionally higher costs easements and real estate acquisitions, these costs are separately calculated and excluded from the typical 25% markup for engineering, administration, and legal costs. Land acquisition is required for any construction area or pipeline located outside of the public right-of-way. However, if the alignment of the trunk sewer is within a new development being constructed, it is assumed that the easement will be granted to SASD as a condition of the development. Therefore no easement acquisition costs will be incurred by SASD. Easements can vary in cost. SASD usually acquires permanent easements at 50 percent of the land s fee value as determined by an independent appraiser. Temporary easements are acquired at 10 percent of the appraised fee value for a 12-month usage period. Because of unexpected delays to project schedules, temporary easements are typically obtained six months beyond the need of the easement or a minimum of two years, whichever is greater. To ensure that property owners work with SASD, the minimum price for a temporary construction easement and a permanent easement is $500 and $1,000, respectively. Based on Sacramento County Assessor s data for 2010, undeveloped land values can greatly depending on the location of property but, averages around $8 per square foot. Being a planning level document and real estate typically representing a small percentage of the project cost, it is appropriate at this level to not distinguish between uses of land and to apply the following costs: SASD Acquisition Cost : $7,000 per parcel Easements in a Newly Constructed Development: No cost to SASD Temporary Construction Easement (80 feet width) : $0.80 per square foot per year Permanent Easement (20 feet wide for pipelines, 120 x 120 feet for pump station): $4.00 per square foot 2010 SCP Tech Memo - 7 Cost - Final.Docx Page 16 of 18 November 29, 2011

17 3.10 Engineering, Administration, and Legal Costs Typically, a markup is applied to the Estimated Construction Cost to account for the various costs in bringing a planning level concept through design, construction, and closeout. The engineering, administration, and legal cost item will account for all reasonably anticipated cost items for both the design and a construction phase, assumed: Engineering, Administration, and Legal Costs: 25% of the Total Estimated Construction Cost This cost item includes and excludes the following: Include: Project Development Plan 1 & 2 SASD Design/Project Management Flow Monitoring and Capacity Analysis Consultant Design Environmental Clearance (Mitigated Negative Declaration) Permitting Typical Public Outreach Construction Inspection Construction Survey Construction Costs Administration Costs Legal Costs Does not include: Program Cost associated with implementing District s Capital Improvement and Trunk Expansion Programs Easements nor Real Estate Acquisitions 2010 SCP Tech Memo - 7 Cost - Final.Docx Page 17 of 18 November 29, 2011

18 4. REFERENCES Tabula Version King County, Washington, November 10, 2010 CSD-1 Master Plan 2000, Technical Memorandum No. 8B, August 1, 2000 CSD-1 Master Plan 2006, Master Plan TM No. 8B - Cost Research Results, February 23, 2006 SASD Standards and Specifications, June 22, 2011, Version 1.0 County of Sacramento Construction Standard Specification, January 2008 SASD New Construction Bid Summary 2000 to RSMeans Heavy Construction Cost Data, 24th Annual Edition Ebidboard.com for public agency construction bids from 2008 to 2010 Engineering News-Record, Construction Cost Index SASD Sewer Ordinance, April 8, Sacramento County Assessor s Office Commercial and Land Sales for 2010 Interceptor Sequencing Study 2010 SCP Tech Memo - 7 Cost - Final.Docx Page 18 of 18 November 29, 2011

19 COST APPENDIX

20 ENR CONSTRUCTION COST INDEX Assumption: Adjust cost to January 2011 dollars using Engineering News Record Construction Cost Index (ENR CCI) Out of the 20 cities ENR produces cost indices for, San Francisco is the city closest to Sacramento. However, Sacramento costs are typically lower thank San Francisco's cost. Therefore to determine the ENR CCI for Sacramento, take the average ENR CCI of San Francisco and the 20 cities average. January 2011 ENR CCI = average of San Francisco ENR CCI (10116) and 20 Cities ENR CCI (8938) = 9827 Year San Fancisco CCI 20 Cities Average CCI Average CCI 2011 Cost Mark Up Factor

21 GRAVITY PIPELINE COST Year Description Project Jurisdiction Length Unit Median inch VCP Lower Silver Creek Flood Protection and Creek Restoration Project Interstate 680 to Moss Point Drive (Reaches 4,5, & 6A) Santa Clara Valley Water District Costing Range 50% 150% Weighted Average Adjusted 2011 Cost (ENR CCI 9527) 405 LF $145 $73 $218 $158 $162 $145 $130 $200 Construction Bid inch VCP Franklin Crossing Major Roads Phase 1 City of Elk Grove 636 LF $69 $34 $103 $65 $66 $58 $70 $67 $ inch VCP Parke Bridge Trunk Sewer City of Elk Grove 124 LF $160 $80 $240 $155 $174 $150 $116 $375 $194 $160 Sacramento Housing and inch VCP Redevelopment Agency 1890 LF $125 $63 $188 $126 $146 $125 $225 $125 $110 $145 Laguna Ridge Whitelock Parkway inch VCP Segment 1 City of Elk Grove 254 LF $166 $83 $249 $166 $193 $166 Laguna Ridge Whitelock Parkway inch VCP Segment 2 City of Elk Grove 1787 LF $145 $73 $218 $145 $168 $ inch VCP Olive Avenue Sewer Trunk Extension County of Sacramento 274 LF $275 $138 $413 $306 $354 $275 $336 $ inch VCP NVS Phase A1 Infrastructure Sacramento 192 LF $290 $145 $435 $247 $287 $150 $302 $ inch VCP Laguna Ridge (North Shed C) Sacramento 1730 LF $135 $68 $203 $130 $157 $84 $130 $165 $140 Gravity Sewer Installation and Sewer inch VCP Lift Station Demolition at Oceanhill City of Huntington Lane from Oceanhill Lane to Beach Beach Boulevard at Adams Avenue 335 LF $210 $105 $315 $206 $210 $175 $210 $120 $310 $215 Castro Valley Sanitary Trunk Sewer inch VCP Project County of Alameda 254 LF $200 $100 $300 $187 $191 $130 $140 $260 $131 $208 $200 $ inch VCP Elk Grove Major Roads City of Elk Grove 5726 LF $50 $25 $75 $50 $56 $48 $46 $50 $57 $48 $48 $109 $86 $ inch VCP Elk Grove Major Roads City of Elk Grove 1021 LF $62 $31 $93 $65 $73 $55 $52 $54 $62 $54 $91 $106 $93 $63 Laguna Ridge Whitelock Parkway inch VCP Segment 1 City of Elk Grove 835 LF $195 $98 $293 $195 $226 $195 Laguna Ridge Whitelock Parkway inch VCP Segment 2 City of Elk Grove 1584 LF $170 $85 $255 $170 $197 $ inch VCP NVS Phase A1 Infrastructure Sacramento 269 LF $250 $125 $375 $249 $289 $166 $331 $250 Lower Silver Creek Flood Protection 2010 and Creek Restoration Project Santa Clara Valley 12 inch VCP Interstate 680 to Moss Point Drive Water District (Reaches 4,5, & 6A) 290 LF $180 $90 $270 $193 $197 $150 $180 $ inch VCP Franklin Crossing Major Roads Phase 1 City of Elk Grove 1143 LF $91 $46 $137 $87 $89 $75 $92 $90 $ inch VCP Laguna Ridge Bruceville Road Phase II City of Elk Grove 1254 LF $96 $48 $144 $95 $103 $145 $94 $ inch VCP Olive Avenue Sewer Trunk Extension County of Sacramento 521 LF $190 $95 $285 $168 $194 $190 $190 $ inch VCP Bruceville Road Segment A City of Elk Grove 649 LF $170 $85 $255 $170 $197 $ inch VCP Laguna Ridge (North Shed C) Sacramento 557 LF $165 $83 $248 $156 $189 $115 $170 $180 $160

22 Year Description Project Jurisdiction Length Unit Median Costing Range 50% 150% Weighted Average Adjusted 2011 Cost (ENR CCI 9527) Construction Bid inch VCP Aerojet Interceptor 1B County of Sacramento 106 LF $358 $179 $536 $346 $402 $255 $330 $415 $ inch VCP Laguna Ridge (North Shed C) Sacramento 4048 LF $193 $96 $289 $190 $229 $138 $195 $190 $235 Castro Valley Sanitary Trunk Sewer inch VCP Project County of Alameda 2691 LF $200 $100 $300 $212 $216 $200 $180 $200 $252 $188 $250 $ inch VCP Lake Murray Trunk Sewer City of San Diego 2549 LF $147 $74 $221 $132 $138 $92 $120 $160 $150 $92 $95 $134 $225 $170 $147 $163 Magnolia Fillmore Golden Sewer From inch VCP SR 91 to Cochran Avenue City of Riverside 1340 LF $175 $88 $263 $164 $167 $121 $140 $150 $183 $120 $185 $175 $195 $205 Magnolia Fillmore Golden Sewer From inch VCP SR 91 to Cochran Avenue City of Riverside 2075 LF $185 $93 $278 $184 $188 $134 $162 $185 $173 $175 $199 $225 $195 $ inch VCP Laguna Ridge (North Shed C) Sacramento 1191 LF $225 $113 $338 $225 $273 $181 $250 $200 $ inch VCP Laguna Ridge (North Shed C) Sacramento 4631 LF $279 $139 $418 $263 $318 $209 $286 $277 $ inch VCP Natomas Phase 1 County of Sacramento 2904 LF $391 $196 $587 $393 $476 $391 $348 $ inch VCP Natomas Phase 2 County of Sacramento 1058 LF $600 $300 $900 $526 $636 $451 $1,100 $600 Castro Valley Sanitary Trunk Sewer inch VCP Project County of Alameda 1161 LF $300 $150 $450 $299 $305 $320 $260 $240 $389 $253 $300 $330 Castro Valley Sanitary Trunk Sewer inch VCP Project County of Alameda 2265 LF $251 $126 $377 $267 $272 $250 $260 $250 $263 $251 $350 $ inch VCP Lake Murray Trunk Sewer City of San Diego 1163 LF $200 $100 $300 $197 $204 $167 $200 $190 $225 $150 $155 $163 $200 $275 $241 $ inch VCP Laguna Ridge (North Shed C) Sacramento 1130 LF $343 $171 $514 $320 $387 $224 $335 $350 $ inch VCP Aerojet Interceptor 1B County of Sacramento 201 LF $438 $219 $656 $428 $496 $425 $375 $450 $ inch VCP NVS Phase A1 Infrastructure Sacramento 1929 LF $290 $145 $435 $292 $338 $303 $282 $ inch VCP Lake Murray Trunk Sewer City of San Diego 3668 LF $247 $124 $371 $234 $244 $152 $250 $205 $240 $247 $210 $184 $270 $270 $317 $ inch VCP Laguna Ridge (North Shed C) Sacramento 222 LF $410 $205 $615 $390 $472 $229 $450 $370 $510 Sacramento Housing and inch VCP Redevelopment Agency 2940 LF $705 $353 $1,058 $693 $804 $720 $640 $535 $705 $867 Sacramento Housing and inch VCP Redevelopment Agency 910 LF $500 $250 $750 $465 $540 $830 $500 $456 $440 $867 Sacramento Housing and inch VCP Redevelopment Agency 705 LF $565 $283 $848 $493 $571 $930 $565 $473 $440 $ inch VCP NVS Phase A1 Infrastructure Sacramento 6123 LF $325 $163 $488 $353 $410 $425 $325 $ inch VCP Aerojet Interceptor 1B County of Sacramento 2677 LF $453 $226 $679 $483 $560 $415 $400 $490 $625

23 Pipe Cost $1,000 $800 $600 $400 $200 $0 Pipe Cost vs Pipe Diameter Pipe Diameter (in) Series1 Linear (Series1) y = 14.45x R² = VCP GRAVITY PIPELINE COST Pipe Size Cost Depth 8' to 16' 16' to 20' 20' to 24' 24' to 28' to 16 $ to 16 $ to 16 $ to 16 $ to 16 $ to 20 $ to 20 $ to 20 $ to 20 $ to 24 $ to 24 $ to 24 $577 MANHOLE COST PER LINEAR FOOT Manholes 48 inch Manhole < 16 feet deep Pipe inch Manhole > 16 feet deep Pipe inch Manhole < 16 feet deep Pipe 24< 60 inch Manhole > 16 feet deep Pipe 24< 72 inch Manhole > 16 feet deep USE THIS FOR GRAVITY PIPELINE COST Average Cost Spacing 400 Spacing 500 Pipe Size 8' to 16' 16' to 20' 20' to 24' 24' to 28' VCP N/A 27 VCP N/A 16 VCP N/A 32 VCP N/A 38 VCP VCP VCP VCP VCP VCP VCP VCP RCP RCP CHECK MASTER PLAN 2006 ADJUSTED VALUES (ENR CCI 8064) 8' to 16' 16' to 20' 20' to 24' 24' to 28' Pipe Size Adjusted Adjusted Adjusted Adjusted Value Variance Variance Variance Value Value Value Variance 6 N/A N/A N/A N/A 8 $177 $17 N/A N/A N/A 10 $201 $11 N/A N/A N/A 12 $224 $4 $236 $1 $260 $0 $284 $1 15 $260 $5 $284 $9 $295 $5 $319 $6 18 $295 $10 $319 $9 $343 $3 $366 $4 21 $331 $1 $354 $1 $378 $7 $402 $13 24 $366 $1 $390 $0 $413 $7 $449 $1 27 $402 $7 $425 $5 $461 $6 $496 $6 30 $437 $7 $461 $1 $496 $1 $532 $2 33 $473 $8 $508 $13 $543 $13 $579 $14 36 $508 $13 $543 $13 $579 $9 $626 $16 39 $532 $2 $579 $14 $614 $9 $662 $17 Check Okay 42 $567 $2 $614 $14 $662 $22 $709 $29

24 FORCE MAIN COST Assumption: Force mains to be in depth range of 4 to 16 feet. Force mains located deeper than 16 feet, use unit cost for gravity pipe. Force main to be ductile iron pipe. Air release valves and manhole vault to be installed every 3000 feet (included in unit price for force main). Description 4" DIP less than 10 feet deep 4" DIP 10 to 16 feet deep 6" DIP less than 10 feet deep 6" DIP 10 to 16 feet deep 8" DIP less than 10 feet deep 8" DIP 10 to 16 feet deep 10" DIP less than 10 feet deep 10" DIP 10 to 16 feet deep 12" DIP less than 10 feet deep 12" DIP 10 to 16 feet deep 15" DIP less than 10 feet deep 15" DIP 10 to 16 feet deep 18" DIP less than 10 feet deep 18" DIP 10 to 16 feet deep 21" DIP less than 10 feet deep 21" DIP 10 to 16 feet deep 24" DIP less than 10 feet deep 24" DIP 10 to 16 feet deep Pavement Intermediate Hauling of Cost Per Trench ARV Installation Pipe and Backfill & Removal/Temporary Dewatering Pipe Bedding Backfill & Excess Native Total Cost Linear Excavation and Manhole Installation Compaction Replacement Compaction Material Foot Use CY $/CY CY $/CY CY $/CY LF $/LF LF $/LF CY $/CY CY $/CY CY $/CY LS $/LS $ $/LF $/LF 500 $ $ $ $ $ $ $ $ $12.00 $140,783 $141 $ $ $ $ $ $ $ $ $ $8.00 $200,050 $200 $ $ $ $ $ $ $ $ $ $12.00 $146,613 $147 $ $ $ $ $ $ $ $ $ $8.00 $205,880 $206 $ $ $ $ $ $ $ $ $ $12.00 $150,573 $151 $ $ $ $ $ $ $ $ $ $8.00 $209,840 $210 $ $ $ $ $ $ $ $ $ $12.00 $167,073 $167 $ $ $ $ $ $ $ $ $ $8.00 $226,340 $226 $ $ $ $ $ $ $ $ $ $12.00 $182,473 $182 $ $ $ $ $ $ $ $ $ $8.00 $242,407 $242 $ $ $ $ $ $ $ $ $ $12.00 $245,740 $246 $ $ $ $ $ $ $ $ $ $8.00 $324,762 $325 $ $ $ $ $ $ $ $ $ $12.00 $276,315 $276 $ $ $ $ $ $ $ $ $ $8.00 $355,337 $355 $ $ $ $ $ $ $ $ $ $12.00 $301,065 $301 $ $ $ $ $ $ $ $ $ $8.00 $380,087 $380 $ $ $ $ $ $ $ $ $ $12.00 $352,815 $353 $ $ $ $ $ $ $ $ $ $8.00 $431,837 $432 $430 Use these cost for force mains Force Main Diameter (in) Less than 10 Feet 10 to 16 Feet Deep Deep Cost ($/lf) Cost ($/lf) Force main 60 inch Manhole < 16 feet deep Air Release Valve ARI Nylon D 20 Cost per LF Based on Spacing of 3,000 feet Cost $8,000 $2,500 $4

25 BORE AND JACK COST Assumptions: Bore and jack unit cost include mobilization and demobilization cost and carrier pipe and installation cost. Bore and jack unit cost does not include jacking and receiving pit cost. Carrier Pipe Diameter (in) Steel Casing Pipe Diameter (in) Bore and Jack Cost ($/lf) Pipe and Installation Cost ($/lf) Total Bore and Jack Cost ($/lf) Use this for Bore and Jack Unit Cost ($/lf) $40.50 $616 $ $51.50 $627 $ $56.00 $631 $ $78.00 $653 $ $42.50 $668 $ $46.50 $722 $ $58.00 $793 $ $79.00 $844 $ $87.50 $888 $ $ $945 $ $ $1,038 $1, $ $1,104 $1, $ $1,165 $1,165

26 Assumptions: Average production rate is 32 to 60 feet per day. MOBILIZATION AND DEMOBILIZATION Typical mobilization cost approximately $44,000 per day. MICROTUNNELING COST Unit price of microtunnel includes the cost of bore and carrier pipe. Mobilization and demobilization is separate. Smaller pipelines (15 inch diameter or smaller) will be using microtunneling for force mains, pipe material will be ductile iron. Larger pipeline (18 inch diameter or greater) will be using microtunneling for trunk sewers, pipe material will be reinforced concrete. Jacking and receiving pits will be separate items and are not included in the unit cost of pipe ramming. Bore Hole Diameter Less than 24 inch 24 to 48 inch Greater than 48 inch Mobilization/ Demobilization ($/Day) $44,000 $44,000 $44,000 Traveling Days Mobilization/Demobilization Cost (Job) $110,000 $180,000 $260,000 MICROTUNNEL Pipe Diameter (in) 8 DIP 10 DIP 12 DIP 15 DIP 18 RCP 21 RCP 24 RCP 27 RCP 30 RCP 33 RCP 36 RCP 39 RCP 42 RCP Use this for Tunnel Tunnel Tunnel Equipment Casing Carrier Microtunnel Microtunnel Diameter Production Rate Equipment Technician Installation Pipe Unit Cost Unit Cost (in) (lf/day) ($/lf) ($/lf) ($/lf) ($/lf) ($/lf) ($/lf) 8 60 $75.00 $10.33 $ $0.00 $819 $ $75.00 $10.33 $ $0.00 $819 $ $75.00 $10.33 $ $0.00 $819 $ $77.59 $10.69 $ $0.00 $847 $ $77.59 $10.69 $ $0.00 $847 $ $81.82 $11.27 $ $0.00 $893 $ $90.00 $12.40 $ $0.00 $982 $ $90.00 $12.40 $ $0.00 $982 $ $90.00 $12.40 $ $0.00 $982 $ $90.00 $12.40 $ $0.00 $982 $ $90.00 $12.40 $ $0.00 $982 $ $90.00 $12.40 $ $0.00 $982 $ $90.00 $12.40 $ $0.00 $982 $ $90.00 $12.40 $ $40.50 $1,023 $1, $90.00 $12.40 $ $51.50 $1,034 $1, $90.00 $12.40 $ $56.00 $1,038 $1, $90.00 $12.40 $ $78.00 $1,060 $1, $90.00 $12.40 $ $42.50 $1,025 $1, $90.00 $12.40 $ $46.50 $1,029 $1, $91.84 $12.65 $ $58.00 $1,060 $1, $ $15.50 $ $79.00 $1,124 $1, $ $15.83 $ $87.50 $1,154 $1, $ $16.91 $1, $ $1,240 $1, $ $18.15 $1, $ $1,336 $1, $ $20.11 $1, $ $1,479 $1, $ $23.25 $1, $ $1,702 $1,700

27 PIPE RAMMING COST Assumptions: Pipe ramming is most useful in short drives and shallow applications. Mobilization and demobilization cost will be included in the unit price of pipe ramming. Pipe installation cost will also be include in the price of pipe ramming. Due to the lack of available cost information on pipe ramming, unit price cost for pipe ramming will be obtained from ENR CCI adjustments from Master Plan Casing to accommodate carrier pipe bell plus 12 inches. Smaller pipelines (15 inch diameter or smaller) will be using pipe ramming for force mains, pipe material will be ductile iron. Larger pipelines (18 inch diameter or greater) will be using pipe ramming for trunk sewers, pipe material will be reinforced concrete. Jacking and receiving pits will be separate items and are not included in the unit cost for pipe ramming Casing Size 37 inch 40 inch 42 inch 47 inch 55 inch 56 inch 61 inch 63 inch 68 inch 71 inch 76 inch 80 inch 84 inch Pipe Ramming Cost 2000 (ENR CCI 6474) ($/lf) Adjusted Pipe Ramming Cost (ENR CCI 9527) ($/lf) Pipe Size Pipe and Installation Cost ($/lf) Pipe Type Total Pipe Ramming Cost ($/lf) Use this for Pipe Ramming Cost ($/lf) $180 $265 8 inch $40.50 DIP $305 $305 $200 $ inch $51.50 DIP $346 $345 $220 $ inch $56.00 DIP $380 $380 $260 $ inch $78.00 DIP $461 $460 $315 $ inch $42.50 RCP $506 $505 $315 $ inch $46.50 RCP $510 $510 $330 $ inch $58.00 RCP $544 $545 $365 $ inch $79.00 RCP $616 $615 $390 $ inch $87.50 RCP $661 $660 $420 $ inch $ RCP $718 $720 $480 $ inch $ RCP $819 $820 $520 $ inch $ RCP $889 $890 $560 $ inch $ RCP $959 $960