stormwater compliance cip master plan & la …...• stormwater rehab program (no. 0260)...
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STORMWATER COMPLIANCE CIP MASTER PLAN &LA CIENEGA PARK & FRANK FENTON FIELD
REGIONAL STORMWATER PROJECT
August 8, 2019
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Identify additional Stormwater project opportunities for EWMP compliance
Develop project concepts
Develop Overall Plan to capture 87 acre-ft of stormwater runoff during the 85th percentile 24-hr storm event Rain fall intensity of 1.1 in/hr. for the region
Budget and prioritize CIP projects, 20-year planning horizon
STORMWATER COMLIANCE CIP MASTER PLAN OBJECTIVES
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SUMMARY OF STORMWATER COMPLIANCE CIP MASTER PLAN
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Key Data for Public Land Existing Land Use, Topography, Surface
Drainage Stormwater Infrastructure Soil Survey Data 2016 Roadway Condition Assessment
Report
Process identified distributed sites providing over 83 acre-ft potential stormwater capture
Site Visits provided confirmation for each type
BMP DEVELOPMENT PROCESS
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Curb Extensions
Median Bioretention Permeable Pavement
Sidewalk
Vaults
Residential Programs
Subsurface Storage
BMP CONCEPTS FOR STORMWATER CAPTURE
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Prioritization Objectives• Maximize Stormwater Volume Capture• Coordinate with City Projects to
Minimize Disturbance• Reduce Access Issues by utilizing City
owned properties• Proximity to Stormwater Infrastructure
reduces additional infrastructure needs
Future Prioritization Opportunities• Complete Streets Plan (CIP No. 0100)• Water Main and Hydrant Replacement
Plan (CIP No. 0387)• Land Acquisition (CIP No. 0647)• Street Tree Removal (CIP No. 0089)• Alley Repaving (CIP No. 0080)• Stormwater Rehab Program (No. 0260)
PRIORITIZATION OF PROJECT SITES
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EWMP Cost Development2016 EWMP Cost Functions were used to establish planning level costs. These were developed by refining 2011 LACFCD Watershed Management Modeling System (WMMS) cost functions
CIP Cost DevelopmentTypical Project Bid Tabs developed for each project category, providing:
• More detailed assessment of project components
• Project costs informed by current dollars
• Average unit costs for Los Angeles area
• Vendor costs obtained for specific items.
• Construction Contingency of 30%• Additional 20% for Planning and
Design
2016 Ballona Creek EWMP Cost Functions
2019 Stormwater CIP: BMP Facility Refined Costs
REFINING COST OPINIONS
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UPDATED COST COMARISON
Already Planned via
City-adopted Ordinances 2015
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UPDATED COST COMARISON
TOTAL CAPITAL COST (2016): $71.95M TOTAL PLANNED CAPITAL COST(2019): 110M
TOTAL EXISTING PROJECT COST: $10.5M
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CIP PROJECT SUMMARIES
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CIP IMPLEMENTATION TIMELINE Informed by Design Professionals, Estimators,
Proprietary Device Suppliers, Contractors Year 1 - Planning, Design, Permitting Costs Year 2 – Construction Replacement or restoration considered post-CIP Public outreach and engagement should be
integrated throughout planning, design, and construction phases.
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CIP IMPLEMENTATION SUMMARY
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This CIP provides capture and
treatment of an additional 72.4acre-ft of stormwater runoff, during
each storm event greater than or
equal to 1.1 inches, the 85th
percentile storm event.
Approximately 840 acres of
impervious drainage area will be
treated through various
structural and non-structural
BMP and LID strategies, ensuring
EWMP compliance.
STORMWATER CAPITAL IMPROVEMENT PROGRAM IMPACT
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Already Planned via
City-adopted Ordinances 2015
PRELIMINARY DESIGN
REPORT
LA CIENEGA PARK & FRANK FENTON FIELD STORMWATER PROJECT
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Evaluate Feasibility of Enhanced Watershed Management Plan (EWMP) Recommended Project
Develop and evaluate feasible Project Alternatives
Identify Recommended Project Alternative and Develop Preliminary Design
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LA CIENEGA PARK
FRANK FENTON FIELD
PRELIMINARY DESIGN REPORT OBJECTIVES
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Project Criteria EWMP Recommendations
Capture Volume Goal 24 acre-feet
City Watershed Contribution
City of LA significant contributor
BMP Type Groundwater Infiltration/Recharge
Site Layout Requirement
Use of all baseball fields
Project Cost $32.2m
OVERVIEW OF EMWP RECOMMENDED PROJECT
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County Requirements for Stormwater Infiltration projects include: Infiltration rate >.3 inches per hour Invert of stormwater infiltration >10’ above
groundwater Infiltration shall not increase potential for
seismic settlement due to liquefaction Infiltration shall not increase potential
settlement of structures on or adjacent to site
Results of hydrogeological investigations: Site infiltration rate: .01 inches per hour Site soils: interbedded granular soils subject to
liquefaction
UPDATED HYDROGEOLOGICAL INVESTIGATION RESULTS
Geotechnical and Hydrogeological Investigations Indicate Infiltration is Not Feasible
Alternative Options Include:
Harvesting and Direct use at the Park
Treatment and Discharge back to the MS4
Diversion to the Sanitary Sewer
Requires detaining stormwater volume for 24 hours after storm event.
No treatment required.
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PROJECT ALTERNATIVES
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UPDATED HYDROLOGY ASSESMENT
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CATEGORY EWMP RECOMMENDATIONS UPDATED RECOMMENDATIONS
Capture Volume Goal 24 acre-feet 21 acre-feet
City Watershed Contribution City of LA significant contributor City of Beverly Hills main contributor
BMP Type Groundwater Infiltration/Recharge
Subsurface Detention and Diversion to Sanitary Sewer
Site Layout Requirement Use of all baseball fields Use of one baseball field
Project Cost $32.2m $20.2m
SUMMARY OF FEASIBILITY STUDY
• Stormwater diversion, storage, and release to LASAN’s sanitary sewer system
• Detain stormwater volume for 24 hours after storm event
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ALTERNATIVE COST COST PER GALLON
DETAINED
COMPARISON BETWEEN ALTERNATIVES
Alternative 1 – Modular Precast
Detention Tank
$20.2 million $2.96 Gravity flow to detention tank results in less pumps /
O&M
High excavation volumes
Lowest cost
Alternative 2- Prestressed
Concrete Detention Tank
$25.6 million $3.74 More pumps / O&M required to pump to detention
tank
Less excavation volumes
Alternative 3 - Cast-In-Place
Concrete Detention Tank
$37.6 million $5.49 Less pumps / O&M
High excavation requirements
High concrete requirements
Highest cost
RECOMMENDED PROJECT ALTERNATIVE
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ALTERNATIVE 1 – MODULAR PRECAST DETENTION TANK
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PRELIMINARY ENGINEERINGDESIGN
PARAMETER VALUE
Maximum Flow into Tank,
cubic feet per second
14
Capacity, MG 6.84
Tank Invert Elevation, feet 105
Tank Height, feet 15
Tank Foundation To Be Determined by Basin
Manufacturer
Tank Footprint, feet 276 x 243
Inlet/Outlet Pipe Diameter,
inches
48
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DESCRIPTION TOTAL DIRECT COSTTOTAL INDIRECT
COST
TOTAL
CONSTRUCTION
COST
Division 1 $109,000 $46,000 $154,000
Safety Equipment $109,000 $46,000 $154,000
Division 2 $4,702,000 $1,926,000 $6,627,000
Site Preparation $1,265,000 $519,000 $1,782,000
Earthwork $3,034,000 $1,243,000 $4,276,000
Buried Piping $134,000 $56,000 $188,000
Site Improvements and Amenities $170,000 $72,000 $240,000
Dewatering $100,000 $43,000 $141,000
Division 3 $4,406,000 $1,804,000 $6,209,000
Precast Concrete $4,406,000 $1,804,000 $6,209,000
Division 11 $683,000 $281,000 $963,000
Water Supply & Treatment Pumps $683,000 $281,000 $963,000
Total Construction Cost $13,953,000
Construction Contingency (30%) $4,186,000
Construction Management (5%) $698,000
Planning and Design Cost (10%) $1,396,000
Total Estimated Project Cost $20,233,000
Direct Cost Labor Equipment Sub-Contractor
Indirect Cost General
Requirements Contractor Fee Insurances & Bond
PROJECT OPINION OF PROBABLE COST
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PROJECT FEATURE ACTIVITY1 FREQUENCY ANNUAL O&M COST
Stormwater Diversion Structure Inspect diversion structure, remove gross
solids with a vacuum truck
Annually $9,600
Trash Rack Remove gross solids with a vacuum truck Monthly & After Rain Events $28,800
Detention Tank Inspect interior of tank After Rain Events $24,000
Detention Tank Clean interior of tank with a vacuum truck Bi-Annually $9,600
Pump Station Electrical power Daily low flow diversion,
assumed 10 storm events
$3,700
Pump Station Inspect and maintain pumps including
lubrication and cleaning
Monthly $14,400
Pump Station Remove gross solids from sump with a vacuum
truck
As Needed $9,600
Pump Station Inspect and maintain instrumentation and
controls
As Needed $4,800
Pump Station Replacement parts As Needed $20,500
Total Estimated Annual O&M Cost $125,000
30 Year Total Life Cycle O&M Cost2 $6,400,0001Assumes City will contract out maintenance activities with labor cost of $150 per hour230-Year Life Cycle O&M Cost based on 3% O&M inflation, 5% annual energy increase
OPERATIONS AND MAINTENANCE COST
City Stormwater Enterprise Fund
(SEF)
Stormwater User Fees
Cash FinancingPotential Funding
Safe Clean Water Program
(Measure W)
General Obligation Bond/ Revenue Bond Financing
Clean Water State Revolving Fund Loans (CWSRF)
Water Infrastructure Finance and
Innovation Act (WIFIA)
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FUNDING STRATEGIES
Municipal tax-exempt bonds
20 or 30-year amortization period
Interest rate 4.5% to 5% or higher
Federal-state partnership
20-year amortization period
Low-cost financing
Interest Rate 1.7% to 2.0%
Administered by the EPA
35-year amortization period
Funds 49% of the total cost
Interest Rate 3% plus, equal to or greater than the Treasury rate as of the date of closing
Municipal Program(40% = 560K)
Regional Program (50% = 700K)
County of LA(10% = 140K Admin)
Insufficient over the years
City can’t raise fee without going to ballot, Prop 218
Transfers-in from the City’s General Fund once City Council approves CIP or due to new regulations
Cash financing from General Fund
No debt-financing
Prop 1 via Stormwater Program
Caltrans Stormwater Grant
CURRENT BEVERLY HILLS FUNDING
$20.2M for LCP/FFF Project, recommendation is “Project Financing Mix”
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PROJECT SCHEDULE
WORK ITEM MONTHS YEAR 1 YEAR 2 YEAR 3 YEAR 4
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1
Complete Preliminary
Design (Finalize PDR)3
CEQA Documentation,
Permits10
Complete Final Design /
Deliver Bid Set4
Bid Phase4
Construction Phase18
Public Outreach 36
Total36