Lessons Learned from CM-at-Risk and Design Build Projects at Water and Wastewater Treatment Plants. Lawrence H. Hentz Jr., P.E.

Transcription

1 Lessons Learned from CM-at-Risk and Design Build Projects at Water and Wastewater Treatment Plants Lawrence H. Hentz Jr., P.E., BCEE

2 Presentation Outline Background of Two >$110 M Projects Improvements That Were or Are Being Constructed Reasons Why Design Build and CM at Risk Project Delivery Methods Were Selected Lessons Learned During Design and Construction 2

3 Little Patuxent Water Reclamation Plant 26 mgd Modified Johannesburg Process Traveling Bridge Filters Centrifuges and RDP 3

4 Dreyer s Grand Ice Cream Plant Dreyer s Grand Ice Cream Started Large Expansion in to 26 production lines by

5 Dreyer s COD Load Influent COD Loading from Dreyer's lb/day Year 5 Avge Max

6 6 Primary Clarifier Effluent BOD Loads

7 Waste Characterization and Treatment Studies 7

8 8 Low Rate Anaerobic Reactor Process Schematic

9 Selected ADI Systems, Inc. Turnkey Delivery Capability Best Able to Achieve Schedule Long DT Process = Lowest Process Risk Good Cost Data Most Similar Experience 17 dairy facilities 3 ice cream facilities 9

10 Summary of Dreyer s Grand Ice Cream Pretreatment Facilities Delivered Dreyer s wastewater to the LPWRP via a dedicated sewer Constructed two 4 MG anaerobic reactors and gas utilization facilities Converted existing 1 MG aerobic digesters to Selector-MLE activated sludge process Added special DAF for process upsets Retrofitted existing static primary sludge fermenters to continuous flow fermenters 10

11 Fermenter and Anaerobic/Aerobic Reactors Primary Clarifiers Ax An Ax Oxic Secondary Clarifiers Sand Filters From Dreyers Poly DAFT Gravity Thickners EQ Tank & Fermenter TWAS Storage DAFT Aerobic Reactor Primary Storage Centrifuges CaO RDP

12 Little Patuxent Water Reclamation Plant 26 mgd Modified Johannesburg Process Traveling Bridge Filters Centrifuges and RDP 12

13 13 Anaerobic Reactors

14 Anaerobic Reactors 14 Dutchland Post Tension Tanks

15 15 Aerobic Reactor Selector MLE

16 16 Retrofit MLE Process

17 17 Repairs Thru The Winter 2007

18 18 Dreyer s Pretreatment Improvements

19 Dreyer s Pretreatment Facilities 19 Negotiated A Turnkey Design Build Project Delivery with ADI for Anaerobic Pretreatment Facilities Collaborated on Integrated Design Sufficient for permits Sufficient to establish GMP Used EJCDC Design Build Contract Balanced contract Collaboratively developed by Owners, Engineers, and Contractors

20 Other Improvements 20 CM at Risk Delivery Method Developed an RFQ/RFP and Interviewed 3 Contractors Written proposals Staff, availability, previous experience, bonding, rates, etc Selected Contractor Based on Proposals and Interviews Used Modified EJCDC Negotiated Supplemental Terms and Conditions

21 Project Delivery 21 CM at Risk Allowed design of retrofit facilities to proceed in parallel with construction activities Contractor Became familiar with facilities and established working relationship with design team Refined schedule and developed resource plan Advanced procurement Constructability reviews Initial site work Open book negotiation of costs DBB Quality based selection of Contractor

22 Lessons Learned - Turnkey Bench-mark Costs Verify/validate costs for 3 similar facilities before agree to select vendor Check references Determine project leaders (PM and CM) This Homework Pays Off Leverage in negotiations Changes Comfort for governmental agencies 22

23 Lessoned Learned - Turnkey Engage Governmental Procurement, Permitting and Legal Staffs Early and Often Not comfortable with changing front ends EJCDC works well Need to drive solution Lost 3 to 4 months Be Careful Not to Deviate Too Far from the Industrial Approach Redundancy, flexibility, SCADA Takes precious time and adds substantial scope and money 23

24 Lessons Learned - Turnkey Results $6 M Construction Cost Started in December 2006 Complete in October /10 in Quality and Overall Experience $ in Changes $150,000 Due to contaminated soils and poor subgrade 24

25 Lessons Learned CM at Risk Not Many Contractors in Mid-Atlantic With Similar Experience Especially for smaller projects (<$20M) Check references Make Sure Subs Have Good Working Relationship with GC Get Leaders Who Have Been There, Done That Smaller size projects good for a selfperforming critical portions of the project Encourage cooperative spirit 25

26 Lessons Learned CM at Risk Engage Governmental Procurement, Permitting and Legal Staffs Early and Often Not comfortable with changing front ends EJCDC must be customized Lost 3 to 4 months Use Open Book Negotiations Agree to process/organization Audit or parallel approaches Agree to definitions and scope of contingencies and allowances 26

27 Lessoned Learned CM at Risk 27 Know When to Stop Design and Begin Construction Designers used to defensive design Need to stop when Adequate for permits Adequate for developing good costs Some Disciplines More Difficult Than Others Electrical/Instrumentation Structural Owners Must Be Active Participants Must make timely decisions Increase their understanding

28 Lessons Learned CM at Risk Results $10 M Construction Cost Started in October 2006 Complete in January /10 in Quality and Overall Experience $ in Changes Phase 1 +$29,000 Phase 2 (-$9,200) All other changes covered by allowance or contingency funds 28

29 Summary of ENR Improvements 29 Effluent at 3 mg/l TN and 0.3 mg/l TP Major Retrofit Elements Insert Selectors into BNR process and improve aeration systems and oxygen control Improve flow split to reactors Improve primary and secondary clarifiers New RAS and WAS pumps UV disinfection and post-aeration facilities Biosolids dewatering Major New Facilities One north reactor and clarifier and RAS Denitrification filters and pumping station

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32 Yard Piping Retrofits EXISTING PRIMARY CLARIFIER #10 EXISTING EAST AND WEST PROCESS REACTORS EXISTING RISER BOX EXISTING SECONDAR Y SUBSTATIO N PROPOSED FLOW SPLITTER BOX EXISTING NORTH PUMP STA EXISTING FINAL CLARIFIER #2 EXISTING FINAL CLARIFIER #3 EXISTING FINAL CLARIFIER #4 EXISTING FINAL CLARIFIER #5 NEW SLIDE GATE EXISTING PRIMARY CLARIFIER #1 NEW SLIDE GATE EXISTING PRIMARY CLARIFIER #2 EXISTING PRIMARY CLARIFIER #3 EXISTING PRIMARY CLARIFIER #4 32

33 Project Delivery Issues Complex Mixture of Facilities Retrofit aeration facilities, clarifiers, and centrifuges Old facilities in need of repair New aeration tanks, denitrification filters, and UV MOPO Previous attempts to repair failed - flood Stringent discharge limits Owner Deemed CMR Very Successful 33

34 Project Delivery - CM at Risk 34 Developed an RFQ/RFP and Interviewed 2 Cont-Led CMs & 2 Eng-Led CMs Written quals and tech proposals Staff, availability, previous experience, bonding, rates, etc Selected Contractor Led CM Based on Proposals and Interviews Used Modified EJCDC Negotiated Supplemental Terms and Conditions

35 Lessons Learned CM at Risk Establish SOW and Budget for CM Management Team and Fees During Selection Process Highly variable fees Assists in negotiations during GMP Get Good CM Leaders Who Can Manage MOPO and Many Subs Hire CM No Latter than 50% Design Proactively Address Self-performance Pros and Cons 35

36 Lessons Learned Self Performance Pros Could control critical path construction Emergency response Great understanding of SOW less management Cons Tolerance of poor performance Chilling effect on subcontractor community Balance Needed Limit self-performance to critical items 36

37 Lessons Learned CM at Risk Engage Governmental Procurement, Permitting and Legal Staffs Early and Often Use Open Book Negotiations Substantial Owner involvement in bidder selection and negotiations phases Agree to specific definitions and scope of contingencies and allowances Provide incentives in GMP for extraordinary efforts 37

38 Lessoned Learned CM at Risk CM Must Agree When To Stop Design and Begin Construction When Diminishing Return Achieved Cost of engineering equal or more than reduction in GMP Adequate for controlling subs 38

39 Lessons Learned CM at Risk Results $92.5 M GMP Estimated at $102 M Started in June 2009 Employing Early Start for Site Work Parallels permitting Demolition also included Entire Project To be Complete by December

40 40 Potomac Water Filtration Plant

41 Potomac Water Filtration Plant Constructed in 1961 Provides Drinking Water to over 1 Million People in Montgomery & Prince George s Counties in MD Conventional Treatment Process This Project Included Various Improvements Required to Reliably Treat 288 mgd 41

42 Potomac WFP Improvements Upgrade Rapid Mix Facilities Replace Existing Flocculators New Ultraviolet Disinfection Facilities New Intermediate Pumping Stations New Lime Addition Facilities New Backwash Pumping Facilities Various Electrical Improvements 69 kv to 35 kv 35 kv to 5 kv 42

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44 UV Disinfection Facilities 2 facilities East and West sides of the plant (retrofitted in existing finished water reservoirs) Each side will house 6 48 UV reactors Six lamps per reactor expandable to nine lamps Each facility mgd capacity 1 spare reactor/facility Six intermediate pumps 44

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46 46 Intermediate Pumping

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48 48 UV Disinfection

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53 Project Delivery Issues Significant Retrofit of Large Facilities in Tight Site Conditions IPS and UV in existing Finished Water Reservoirs Old facilities in need of repair Retrofit rapid mixing and flocculation facilities $25 M in primary and secondary electrical facilities MOPO Must keep operational Nothing out-of-service in summer DBB History Very Litigious Desire for Significant MBE/WBE Participation 53

54 Project Delivery - CM at Risk 54 Developed an RFQ/RFP and Interviewed 2 Cont-Led CMs & 2 Eng-Led CMs Written quals and tech proposals Staff, availability, previous experience, bonding, rates, etc Selected Contractor Led CM Based on Proposals and Interviews Modified Clients Front End Documents Negotiated Supplemental Terms and Conditions

55 Lessons Learned CM at Risk Establish SOW and Budget for CM Management Team and Fees During Selection Process Get Good CM Leaders Who Can Manage MOPO and Many Subs and Stays from Design thru Construction Hire CM No Latter than 50% Design Proactively Address Self-performance Pros and Cons 55

56 Lessoned Learned CM at Risk Be Careful in Extending Procurement Phase Lock in major equipment ASAP Make sure bonds on subs are solid Negotiate with MBE/WBEs Continue to Advance Design After Bid If Mutual Agreement Deems it Necessary May need to be somewhat defensive on complex elements Electrical/Instrumentation 56

57 Lessons Learned CM at Risk Results $18.8 M GMP Electrical $89.8 M GMP General CM Started in September 2006 Entire Project To be Complete by January months early About $4 M in Contingency to be Shared Owners Deems Project to be Very Successful No claims 57

58 Questions Thank You Skip Parks and Ken Frederickson