AGENDA REQUEST AGENDA ITEM NO: VI.2. Unfinished Business. June 15, 2015 BY Utilities Mitt Tidwell Utilities Director Tidwell SUBJECT:

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1 AGENDA HEADING: Unfinished Business AGENDA REQUEST COMMISSION MEETING DATE: June 15, 2015 BY Utilities Mitt Tidwell Utilities Director Tidwell AGENDA ITEM NO: VI.2. Originating Department SUBJECT: Department Head Presenter Continued Discussion Re: Lift Station No Construction Alternatives and Funding Options COMMISSION PRIORITIES: Infrastructure EXPLANATION: City staff seeks direction on the Lift Station No. 87 project in terms of the selection of one of the construction alternatives and funding options. ADMINISTRATION'S RECOMMENDATION: Utility Staff will be seeking direction on the design, cost schedule and funding options for the Lift Station No. 87 project. APPROVAL SUMMARY: Approval Department Head Approval Deputy City Manager Approval City Manager Approval City Auditor and Clerk Approval Required Date Completed Y 06/10/2015 Y 06/10/2015 Y 06/10/2015 Y 06/10/2015 Completed By Mitt Tidwell Marlon Brown Marlon Brown Pamela Nadalini Status APPROVED APPROVED APPROVED APPROVED

2 ADDITIONAL EXPLANATION: AGENDA REQUEST ADDITIONAL ADMIN RECOMMENDATION: FUNDING SOURCE: AMOUNT: HOUSING IMPACT (Per House): NEW CONSTRUCTION: REHABILITATION: SUPPORT DEPARTMENTS: $ 0 $ 0 City Auditor and Clerk - Pamela M. Nadalini City Attorney - Robert Fournier Financial Administration - John Lege City Manager - Thomas Barwin COMMISSION ACTION: Final Action Motion: Motion By: AGENDA DISPOSITION Second By: Vote: 2

3 PROJECT UPDATE June 8, 2015

4 Agenda: What led to this point? Project Background Latest Findings Risk Management Alternate Routes Next Steps 2

5 PROJECT BACKGROUND Goals, design process, preliminary work 3

6 Project Goals: Trust & Transparency Environmental stewardship Fiscally responsible approach Manage project risks Minimize impacts to the public 4

7 Project history to date Malcolm Pirnie April 2006 Relocate to former high school parking lot Stantec April 2007 Luke Wood Park and inverted siphon under Hudson Bayou Bridge Boyle AECOM April 2009 Luke Wood Park and microtunnel under Hudson Bayou Bridge 5

8 Project Status U.S Construction begins 2012 Work stops due to microtunnel issues AECOM terminated November 2012 McKim & Creed retained August 2013 Lift Station Issues Operational Structural Osprey Ave. Safety 6

9 New Successor Engineer of Record Review existing design Perform supplemental investigations Create technical memorandums Present to city and public Restart project time of the essence 7

10 Hudson Bayou Crossing Phases Phase I Scope of Work Microtunnel under existing bridge as designed or at revised elevations Horizontal Directional Drill under the existing bridge as inverted siphon Microtunnel under bayou on either side of bridge (alternate alignment) McKim & Creed Recommendation Microtunnel under bridge within the right of way Approved by City Commission Jan. 21,

11 Hudson Bayou Crossing Phases Phase II Scope of Work Finalize microtunnel design (-16.5 feet) Redesign Lift Station 87 McKim & Creed Recommendation Hurricane storm surge protection City Commission direction April 21,

12 Current Design Route U.S. 41 Microtunnel receiving pit Microtunnel jacking pit Current alignment Microtunnel jacking pit Benefits Alternate alignment Maintenance of Traffic Access to Businesses Less US 41 Impacts Hudson Bayou Osprey Ave. 10

13 Hudson Bayou Crossing Microtunnel under bridge Developed by Staheli Trenchless Peer reviewed by Atkins Approved by City Commission Alternate alignment accepted by Staff 11

14 LATEST FINDINGS New studies, inspection data and analysis 12

15 Comprehensive Geotechnical Review borings bathymetric survey, geophysical borings borings survey, concrete cores/testing 13

16 Assessment of Bridge Abutment NORTHWEST CORNER NORTHEAST CORNER SOUTHWEST CORNER SOUTHEAST CORNER 8.75' Original 36" pipe 8.0' Original 36" pipe Proposed 36" microtunnel Proposed 36" microtunnel 8' Concrete core Concrete abutment (surveyed) Concrete abutment (interpreted)

17 Geotechnical Summary North to Mound St. Original pipe Top of pipe elevation: -8.5' Proposed microtunnel Top of pipe elevation: -16.5' 15

18 RISK MANAGEMENT Designs, data and assessments 16

19 Risk Assessment of Designs Original design Lessons learned McKim & Creed design Before bridge investigation McKim & Creed design After bridge investigation 17

20 Risk Register and Criteria IMPACT Low Medium High Probability PROBABILITY Low Medium High 1: 0 20% 2: 20 40% 3: 40 60% 4: 60 80% 5: % Impact 1: < $100 K 2: $100 K $250 K 3: $250K $500K 4: $500 K $1M 5: > $1M 18

21 What is a Risk Register? Identify Issues Risk Score Mitigation Plan Potential Risks Estimate Probability of Occurrence Estimate Impact ($) Probability times Impact Lower the Better Additional Field Work Modify Design Monitor During Construction 19

22 Analysis of microtunneling High jacking force i.e. stuck machine Environmental impact to Hudson Bayou Mixed face conditions hard soils on part of machine, soft on another Unexpected geotechnical conditions Line and grade deviations outside of tolerances Pipe breaking Differing Site Conditions claims Damage to the bridge 20

23 Risk Example: High Jacking Force Mitigation Plan Extensive geotechnical investigations Prescriptive specifications Monitor during construction Probability & Impact Probability reduced from 5 to 1 Impact remains at 5 Risk Score Reduced from 25 to 5 Contingency reduced from $900K to $100K Probability x Impact = Risk Score Note: High Jacking Force happened twice during initial construction. 21

24 Risk Management Results Current design reduces risk significantly from original design Relative Risk score (total) Original design 120 McKim & Creed design Prior to bridge inspection McKim & Creed design Post bridge inspection

25 Additional factors considered Bathymetric Surveys Nettles (2013) Forensic/Hyatt (2014) 6-8 feet 7 feet Geotechnical Borings Foundation Material Phase 1 Report 7-10 feet (each side of bridge) Bridge Inspection (2014) 9 feet (mid Bayou) Reclaimed Water Main (1997) East of Bridge (ROW) Centerline (-16 feet) 23

26 ALTERNATE ROUTES Methods, plans and other considerations 24

27 Open Cut vs. Microtunneling Evaluate options to re-use existing wetwell Open Cut Microtunneling 25

28 Alternate Routes: Control Elevations U.S. 41 Top of Foundation Material (-9.0) Influent MH Invert (-13.08) Wetwell Invert (-13.52) Hudson Bayou Osprey Ave. 26

29 Regulatory Considerations Subaqueous Crossing Regulations Florida Department of Environmental Protection (FDEP) 3 Feet Cover U.S. Army Corps of Engineers (USACE) 6 Feet Cover Top of Pipe El Open cut 27

30 Alternate Route Lincoln Drive U.S " Disrupts condos Permits needed New easement 0 Manhole Osprey Ave. Disrupts home 30" 28

31 Alternate Route Lincoln Drive U.S " Disrupts condos Permits needed New acquisition Hudson Bayou New easement 0 Manhole 24" 30" 29

32 Alternate Route 3 East of Bridge Disrupts park U.S " Permits needed Disrupts home Hudson Bayou New easement 0 Manhole 24" 30" 30

33 Open Cut Considerations Easements and land acquisition required Regulatory permits - FDEP/Sarasota County - Sovereign Submerged Lands - Environmental Resource Permit - FDEP/ACOE Variances Environmental Documented Lead Contamination (2001 Boyle Report) Geotechnical Investigations Borings/Bathymetric Schedule 31

34 Operational Impacts Period submergence of sewer system - Reduced conveyance capacity - More frequent pipeline cleaning - Increased odor potential in neighborhood Hydraulic Institute Standards not met - Un-even flow patterns - Increased frequency of wet well cleaning - Increased wear on one pumping unit - Air entrainment/cavitation - Reduced pumping capacity - Less energy efficiency - Reduced life expectancy for pumps Additional operational and maintenance costs 32

35 Normal Operating Conditions Open Cut Odor Control Elevation ft. Odors Gravity Sewer Overflow hazard Wetwell 33

36 Surcharge Conditions Existing Wetwell Design -TBD ft. Odors Elevation ft. Gravity Sewer Overflow hazard Manhole Existing Wetwell 34

37 Upgrades will still be required Wet Well Slab Modification required to withstand Cat 3 Storm Surge Stand-by Pump Reliability required 35

38 Planning level comparable costs Microtunnel Open Cut current est. 36 Inch (Phase 1) $11.0 M $6.5 M Lift Station 87 (Phase 2) $16.0 M $13.3 M 24 Inch (Phase 3) $5.0 M $5.0 M Land Acquisition - $4.0 M & Legal Environmental - $6.2 M Luke Wood Park - $1.0 M Restoration Total Estimate $32.0 M $36.0 M Open Cut notes: Hudson Bayou crossing assumes variance from state and federal regulation requirements; Land Acquisition & Legal estimated based on city input; Environmental from 2001 Hudson Bayou Stormwater Study 36

39 Analysis of project costs Previous Bid January 2011 Previous Bid indexed to 2015 Current estimate Difference 36 Inch (Phase 1) $1.5 M $1.7 M $11.0 M $9.3 M Lift Station 87 (Phase 2) $5.4 M $6.1 M $16.0 M $9.9 M 24 Inch (Phase 3) $2.7 M $3.0 M $5.0 M $2.0 M Total Estimate $9.6 M $10.8 M $32.0 M $21.2 M Note: 2011 bid indexed to 2015 dollars based on industry-standard methodology. 37

40 Analysis of differences $9.3 M: 36 Inch (Microtunnel) Quotes from recent negotiation attempts $3.0 M: Project Enhancements Replacement of asbestos cement water mains* Installation of reclaimed water mains* Installation of new sewer mains (Pomelo Place) Installation of new water main (Alta Vista to Bahia Vista) Full roadway restoration Landscaped Lift Station 7 site * Osprey, Alta Vista, Pomelo, and/or Pomelo Place 38

41 Analysis of differences $8.9 M: Upgrades Category 3 storm surge protection Operating redundancies Totally enclosed for all operation & maintenance activities Safe working environment for staff Climate change provisions Deeper wetwell/operational efficiencies Site preparation 39

42 NEXT STEPS Resolving design issues, communicating challenges 40

43 Sequencing of Construction U.S. 41 Additional Advantages Risk Management Minimize Disruption to Existing Utilities Cost Controls Hudson Bayou Maintenance of Traffic 41

44 Construction Plan Three Phases Phase 1 36 inch pipe Phase 2 LS 87 construction Demolition of Lift Station 7 and park restoration Phase 3 24 inch pipe Lift Station 7 42

45 Construction Challenges Limited site access Construction zone restrictions Minimize impacts to Luke Wood Park Maintenance of traffic Minimize service disruptions 43

46 Microtunneling Work Zone Receiving shaft work zone U.S. 41 LS site driveway Jacking shaft work zone Construction support work zone Jacking shaft work zone Hudson Bayou 44

47 Microtunnel Work Zone (Osprey) MICROTUNNEL ALIGNMENT HUDSON BAYOU MICROTUNNEL JACKING SHAFT WORK ZONE 45

48 Microtunneling Work Zone (LS 87) JACKING SHAFT EQUIPMENT PIPE STORAGE AREA LS SITE DRIVEWAY OFFICE TRAILER MICROTUNNEL ALIGNMENT 46

49 Building Work Zone APPROXIMATE EXCAVATION LIMITS APPROVED SITE PLAN 47

50 Scheduling and Timeframes Estimates subject to final engineering decisions Bid Phase Start Finish Q 1/2 Q 3/4 Q 1/2 Q 3/4 Q 1/2 Q 3/4 Q 1/2 Q 3/4 Q 1/2 Q 3/4 Q 1/2 Q 3/4 Current Design 36 inch (Phase 1) Lift Station (Phase 2) 24 inch (Phase 3) July 2015 Sept Jan June 2017 June 2019 Aug

51 Project Goals Environmental stewardship - Improve service and system reliability - Storm protection (Category 3 hurricane) - Offset potable water demands with reclaimed water Fiscally responsible approach - Complete Hudson Bayou crossing first - Obtain competitive bid packages - Salvage existing equipment Manage project risks - Pre-qualify microtunneling contractors - Use experienced construction specialists Minimize impacts to the public - Develop detailed MOT plans - Construction updates on project website 49

52 Path to the Next Phase Design Team conclusion Utility Department support Administrative acceptance City Commission direction 50

53 City Commission Direction Actions to move the project forward Pre-qualify specialty contractors Microtunnel under the bridge Pursue alternate alignment Easements will be necessary 51

54 Discussion

55 Lift Station 87 Funding Options 2014 Rate Sufficiency Analysis Annual Rate Increase 53

56 Option 1 Cash while maintaining CIP funding level Defers $20 million of Infrastructure projects Between 2015 and

57 Option 2 Bond debt while maintaining CIP funding level One time rate increase in 2017 In addition to planned 4% No infrastructure projects deferred Rate increase to fund debt service 55

58 Option 3 Bond debt while maintaining CIP funding level No rate increase related to Lift Station 87 Annual 4% rate increase is necessary Defer some infrastructure projects $1.8 million per year until loan is satisfied 56

59 Staff Recommendation Option 3 Bond debt while maintaining CIP funding level No rate increase related to Lift Station 87 Annual 4% rate increase is necessary Defer some infrastructure projects $1.8 million per year until loan is satisfied Finance and Utility Departments will review with rate sufficiency consultant Identify and develop best value option Present to Commission 57

60 Discussion