HomeMy WebLinkAbout12. Amend agreement with Stantec Consulting Services for design of the Filter Plant and Clearwell Improvements - Phase 1A, DP 7361 Page 1 of 29
Item 12.
CENTRAL SAN BOARD OF DIRECTORS
POSITION PAPER
MEETING DATE: MAY 2, 2019
SUBJECT: AUTHORIZE THE GENERAL MANAGER TO AMEND AN EXISTING
PROFESSIONAL SERVICES AGREEMENT WITH STANTEC CONSULTING
SERVICES, INC. TO INCREASE THE CONTRACT CEILING FROM $990,000
TO $1,540,000 MILLION FOR DESIGN OF THE FILTER PLANTAND
CLEARWELL IMPROVEMENTS - PHASE 1A, DISTRICT PROJECT 7361
SUBMITTED BY: INITIATING DEPARTMENT:
CHATHURAABEYRATHNA, ASSOCIATE ENGINEERING AND TECHNICAL SERVICES-
ENGINEER CAPITAL PROJECTS
REVIEWED BY: CRAIG MIZUTANI, SENIOR ENGINEER
EDGAR J. LOPEZ, CAPITAL PROJECTS DIVISION MANAGER
JEAN-MARC PETIT, DIRECTOR OF ENGINEERING AND TECHNICAL
SERVICES
Roger S. Bailey
General Manager
ISSUE
Board of Directors (Board) authorization is required for the General Manager to execute an amendment to
a professional engineering services agreement for amounts greater than $100,000 for agreements
originally valued under$1,000,000.
BACKGROUND
On May 3, 2018, the Board authorized the General Manager to execute an agreement with Stantec
Consulting Services, I nc. (Stantec)for the preliminary design of the Filter Plant and Clearwell
Improvements, District Project 7361 (Filter Plant Project) at a cost ceiling of $990,000. The Stantec
scope of work consisted of numerous field investigations, condition assessments, workshops, meetings
(with Operations, Maintenance, Planning, and Capital Projects), pilot testing, coordination with future
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projects, 3-D scanning, and other important efforts to comprehensively evaluate the Filter Plant and
appurtenant facilities.
Several technical memorandums (TM)were prepared to recommend needed solutions. These
memorandums include: TM 1 - Disinfection; TM 2 - Hydraulic Evaluation; TM 3 - Seismic Assessment;
and TM 4 - Filter Plant Process and Automation. Stantec summarized all the findings in the Alternatives
Analysis Technical Memorandum (TM 5)that will form the basis of design of the Filter Plant Project. This
summary includes filter rehabilitation, chemical conditioning, Clearwell modifications, Clearwell Pump
Station upgrades, and related electrical distribution system upgrades.A scope of work summary of these
improvements is included in Attachment 1.
Overall, the planning level cost for the total project scope outlined in Attachment 1 is estimated at
approximately$53 million. These improvements would provide a reliable Utility Water system for the plant
and serve current and future Zone 1 customers. In addition to this work, Stantec evaluated and
coordinated the project with the future requirements of the Concord Community Reuse Project (CCRP),
formerly known as the Concord Naval Weapons Stations Development Project. This future expansion
would require approximately$35 million in infrastructure improvements to the recycled water system at the
treatment plant.
However, due to the possibility of a water exchange project, the project team re-evaluated the project's
immediate needs, which include the most critical items that require replacement within the next five years
and do not conflict or potentially leave stranded assets due to the water exchange.
Therefore, staff recommends proceeding with a reduced scope of work for the Filter Plant Project to
include the most critical items in a phased approach overtime. The reduced Filter Plant Project, which will
be reflected as Phase 1 A, will include rehabilitation of one filter, recycled water storage, and electrical
modifications as identified in Attachment 2. The total estimated project cost for Phase 1 A is $33 million, of
which $25 million is the construction estimate as shown in Attachment 3. This cost could potentially be
less if the storage tank(s) option proves to be feasible and more cost effective. Eight million of the $33
million is for Design, Staff and Other costs, which would fund the Stantec Consulting Services, I nc. work
of$1,540,000 proposed here.
CEQA
At the December 1, 2016 meeting, the Board independently found that the agreement with this vendor was
exempt from CEQA under Central San's CEQA Guidelines Section 15262, since it allowed for further
planning and feasibility studies for possible future actions which Central San has not approved, adopted, or
funded, and the outcome of these tasks will not have a legally binding effect on later activities. Central San
will conduct an environmental evaluation of any capital project that is proposed in the future as a result of
the tasks authorized herein to determine the need for any additional CEQA documentation.
ALTERNATIVES/CONSIDERATIONS
Although the current budget has adequate cash funding for the final design, it is anticipated that Central
San will most likely request a low interest loan from the State Revolving Fund or request bond financing to
construct the project.This decision will be presented at a future Board meeting and no action is required at
this time.
An alternative would be to not amend the agreement, which is not recommended because the action would
delay staff's ability to implement this project that is intended to maintain a reliable recycled water supply
system that is not only essential for Zone 1 customers but also supplies the treatment plant with utility
water.
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FINANCIAL IMPACTS
The Filter Plant Project- Phase 1 A requires a Stantec agreement amendment of up to $550,000 to
include 30-percent design services for the critical items identified and recommended by staff. The original
Stantec agreement cost ceiling is $990,000, and approval of the $550,000 amendment will increase the
cost ceiling to $1,540,000. Final design services is expected to reach $1 million, which would result in a
Stantec agreement of roughly$2.5 million or 10-percent of the estimated $25 million construction cost.
No change to the project budget is required. The additional Stantec work proposed here can be
accommodated within the multi-year project budget for District Project 7361, Filter Plant and Clearwell
I mprovements, Phase 1 A. The Stantec work is funded within the $8,000,000 pool of funding for Design,
Staff, and other Costs as shown in Attachment 3.
COMMITTEE RECOMMENDATION
The Engineering and Operations Committee reviewed this subject at the April 16, 2019 meeting and
recommended approval.
RECOMMENDED BOARD ACTION
Authorize the General Manager to amend an existing professional services agreement with Stantec
Consulting Services, Inc. to increase the contract ceiling from $990,000 to $1,540,000 for design of the
Filter Plant and Clearwell Improvements - Phase 1A, District Project 7361.
Strategic Plan re-In
GOAL TWO: Strive to Meet Regulatory Requirements
Strategy 1 - Strive to achieve 100%permit compliance in air, water, land, and other regulations
GOAL THREE: Be a Fiscally Sound and Effective Water Sector Utility
Strategy 2- Manage costs
GOAL FIVE: Maintain a Reliable Infrastructure
Strategy 1 - Manage assets optimally throughout their lifecycle
GOAL SIX: Embrace Technology, Innovation and Environmental Sustainability
Strategy 1 -Augment the region's water supply, Strategy 3- Encourage the review and testing of technology to optimize
and modernize business operations
ATTACHMENTS:
1. Filter Plant Project Scope of Work
2. Filter Plant Project- Phase 1 A Scope of Work
3. Estimated Capital Costs of Recommended Items
4. Project Presentation
5. Supplemental Information Presentation
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Attachment 1
Scope of Work Summary
Filter Plant and Clearwell Improvements
District Project 7361
Filter Plant Project
The following is a summary of the scope of work for the Filter Plant Project:
1. Filter Rehabilitation — Condition assessment revealed damaged underdrains and
disturbed gravel in one of the filters. The existing four filters can only reliably
produce 2.25 million gallons a day/per filter (MGD/filter). Filter piping,
instrumentation, and controls should be upgraded to ensure reliable automation
to support continuous operation without full-time operator attendance.
Replacement of two filters was recommended at first, with the other two in the
future.
2. Chemical Conditioning — The existing hypochlorite system is undersized for
current peak demands and the piping system has experienced several failures.
Hypochlorite piping and valves should be replaced. Chemical feed pumps should
be replaced as needed. The alum system should be rehabilitated or retired, and
a new polymer feed system should be installed for conditioning of the filter
influent, based on the pilot test results.
3. Chlorine Contact Basins — Currently, the recycled water system does not have
dedicated chlorine contact basins (CCBs), and the filtered effluent pipeline and
the Clearwell are used to meet the chlorine contact time requirement. Installing
two fixed volume CCBs will optimize the disinfection process, reduce chemical
costs, and allow maintenance of the basins or Clearwell.
4. Clearwell Modifications — The existing membrane cover of the East Clearwell
continues to deteriorate rapidly. It should be removed and replaced with a new
membrane cover. The existing liner should be replaced in both the East and the
West Clearwell. The isolation gates at the Clearwell Inlet Structure and Outlet
Structure should be replaced and retrofitted with gate frames for stop log
placement to allow the gates to be inspected and serviced. The reinforced
concrete divider wall in the Clearwell and adjacent overflow structure should be
structurally modified to meet current seismic standards.
5. Clearwell Pump Station (CWPS) — The existing backwash and applied water
pumps have 2400-volt (V) motors that are inefficient, obsolete, and do not have
variable frequency drives (VFDs) suitable to meet operation needs. Utility Water
(UW) is essential to many treatment plant processes. However, the current UW
system does not have a backup pump. The existing CWPS should be modified
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with the addition of one UW pump to provide firm pumping capacity for UW
service. The 2400V electrical motors of the existing filter Backwash Pumps
should be replaced with new 480V electrical motors to accommodate the
electrical service improvements described below and to enable the installation of
VFDs.
6. Electrical Distribution System — The existing electrical distribution system is
outdated and unreliable. Parts for most of the electrical equipment are no longer
available and difficult to obtain. 2400V systems are no longer used in the industry
due to inefficiency and will be abandoned/replaced with industry standard 480V
and 12kV systems. Changes to the electrical distribution systems include a new
Substation that transforms power from 12kV to 480V to replace Substation 40. All
the existing motor control centers (MCCs) will be demolished, replaced, and
should include VFDs. The new MCCs and VFDs for the CWPS will be housed in
a pre-engineered building designed for weather protection and climate control,
and the remaining electrical will be housed inside the Filter Plant.
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Attachment 2
Scope of Work Summary
Filter Plant and Clearwell Improvements - Phase 1A
District Project 7361
Filter Plant Project— Phase 1A
Staff recommends the following reduced scope of work for Phase 1A:
1. One filter of the existing four filters will be rehabilitated to confirm that the filter
can reliably operate at a filtration capacity of 4.5 MGD/filter. The chemical
conditioning will be limited to the filter replacement and include hypochlorite
piping and valve replacement due to safety concerns.
2. The location and feasibility to install CCBs will be evaluated under this project.
Only a preliminary design concept identifying location and dimensions will be
produced so that staff can designate the area within the treatment plant and will
include a hydraulic analysis.
3. Lifecycle costs for finished recycled water storage tank(s) (pre-stressed concrete
or steel) will be evaluated to compare with the lifecycle costs of rehabilitating and
maintaining the existing Clearwell. If storage tank(s) are cost beneficial, then staff
will include it in the project.
4. Substation 40 will be modified to allow 480V power to the CWPS. The new
MCCs and VFDs for the CWPS will be housed in a pre-engineered electrical
building. A new 12kV electrical feed will be installed from Substation 40 to the
new electrical building.
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Attachment 3
Filter Plant and Clearwell Improvements — Phase 1A
District Project 7361
Estimated Capital Costs of Recommended Items
Design, Staff, Total Total Project
Project Component and Other Costs' Construction Cost
Cost
Filter Improvements $930,000 $3,100,000 $4,030,000
Chemical Conditioning System Rehabilitation $270,000 $900,000 $1,170,000
Clearwell Improvements $3,430,000 $11,100,00 $14,530,000
Clearwell Pump Station Upgrades $910,000 $2,700,000 $3,610,000
Electrical Distribution System Upgrades $2,460,000 $7,200,000 $9,660,000
Total Capital Costs $8,000,000 $25,000,00 $33,000,000
Includes approximately $2.5 million for the Stantec Consulting Services, Inc. professional
engineering services agreement, planning, and construction management.
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Attachment 4
-r.
FILTER PLANT AND CLEARWELL
IMPROVEMENTS, PHASE 1A
DISTRICT PROJECT 7361
Board Meeting
May 2, 2019
Jean-Marc Petit
Director of Engineering and Technical Services
MEN
1 . PROJECT OBJECTIVES AND
BACKGROUND
2
CENTRALSAN
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INITIAL PROJECT OBJECTIVES
• Improve performance and reliability of the Recycled Water Plant(RWP)
o Filtration
o Disinfection
o Recycled Water(RW)storage and distribution (UW and Zone 1)
o Electrical Systems
• Modernize Automation and Control of RWP
o Migrate from batch operation to continuous operation
o Facilitate unattended operation
• Position RWP to meet future RW Title 22 demands
• Maximize asset value of existing facilities --'~- - �•
o Rehabilitate ,
o Repurpose
• Minimize investment in infrastructure for future RWP expansion
• Evaluate Impact and possible integration of Concord Redevelopment and
Water Exchange Projects
3
EXISTING RECYCLED WATER PLANT FACILITIES
Clearwell Pumping Station(PS
• Backwash(BW)Pumps
RW Pumps(Zone 1)
UW Pumps
Clearwell:
East
West —
Substation 40 . West East
CW CWFilters(4) f
eC_
Chemical Conditioning i%„
Filter Effluent Pipeline
Filter BW Basin
Filter Diversion Structure
Forebays 1 `
Applied Water PS
f
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2. PROJECT FINDINGS AND RECOMMENDED
IMPROVEMENTS
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SUMMARY OF KEY FINDINGS AND
RECOMMENDED IMPROVEMENTS
1. Electrical Power Distribution &
Motor Control Centers (MCC) _
2. Structure 9000 and Forebays
3. Filters
4. Clearwell
5. Disinfection
6. Filter Building
6
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3
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Key Project
Clearwell:
Mechanical,
tructural and Failing
Electrical Equipment;and East Cell Clearwell
CWPS Pump Condition and Cover and Liners
Sizing
Combined Storage
and CIz Contact
Filter Capacity and Basins E(f cacy
Condi on
Electrical Power Pipeline antl Pipe
Distribution Voltage Supports Condition
and Reliability
I
Water Quality and
Hydraulic Bottleneck
Filter Building 'Ilkinto Forebays
Condition and Code „f '� ;
Upgrades
i
_ r
o Electrical Equipment;
and
AWPS Pump Condition and
Sizing
3. PROJECT PRIORITIZATION AND PHASING
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RECOMMENDED IMPLEMENTATION
• Split Phase 1 recommendations:
• Phase 1A: Proceed with 30% Design on elements of the
project that would not be impacted by a future Water
Exchange project
• Phase 1 B: Postpone improvement or rehabilitation of other
elements that could be impacted if a Water Exchange project
was to proceed
• Plan for, but not include, elements of Phase 2 into design
which would be triggered and coordinated with CCRP
CENTRAL SAN
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PROPOSED PHASE 1A SCOPE FOR RECYCLED WATER
PLANT FACILITIES IMPROVEMENTS
• Add UW Pump
• Replace BW Motors(480V)
• New 1 MG Storage Tank
a
• Clearwell: -_
• Rehab East Clearwell
Seismic Pining of
divider wall
• New Isolation Gates -
Rehab 1 Filter+mech.
• Upgrade Chemical Feed
New-AbtlPSfBecoaples
Forebays)Retire Fe"ebays -
Y Upgrade/Replace Electrical Gear
RetirexistirtgAWPS r New CW Electrical Facility
Replace Substation 40-2400V
O)
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TOTAL PROJECT COST - PHASE 1A)
Attachment 7
Filter Plant and CI"rwelI Improvements—Phase 1A
District Project 7301
Estimated Capital Costs of Recommended Items
atrx3gn,Staff, Total Total Project
Project Componentand Other Costs' Construction Cost
Filter Improvements $930,900 $3,100,009 $4.030.000
Chemical Condihoning System Rehabilitation $270900 $9001700 $1,170,000
Clearwell Im rovements $3430,900 $11,100,00 $14.530,000
Clearwell Pump Station Upgrades $916,000 $2,700,000 53.610,000
Electrical Distribution System Upgrades $2,460,000 57,200,000 59,660,600
Total Capital Casts $8,000,000 $25,000,OQ $33,000,000
t Includes$2.5 million for Stant-Consulting Services,Inc.professional engineering-m—agreement.
11
4. PROJECT SCHEDULE
PHASE 1A
AML
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Bring 30%
back to E&O
Bring 90%
back to E&O
Submit Application for SRF
`• 13
5. RECOMMENDATIONS
14
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RECOMMENDED BOARD ACTIONS
Staff recommends the following:
Authorize the General Manager to amend an existing
professional services agreement with Stantec
Consulting Services, Inc. to increase the contract ceiling
from $990,000 to $1 .54 million for design of the Filter
Plant and Clearwell Improvements, Phase 1A, District
Project 7361
15
AX
QUESTIONS
161
CENTRAL SAN
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Attachment 5
-r.
FILTER PLANT AND CLEARWELL
IMPROVEMENTS, PHASE 1A
DISTRICT PROJECT 7361
F
Board Meeting
May 2, 2019
SUPPLEMENTAL INFORMATION
SUPPLEMENTAL INFORMATION
PROJECT FINDINGS AND RECOMMENDED
IMPROVEMENTS
jZ
1
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SUMMARY OF KEY FINDINGS AND
RECOMMENDED IMPROVEMENTS
1. Electrical Power Distribution &
Motor Control Centers (MCC)
2. Structure 9000 and Forebays
3. Filters
4. Clearwell
5. Disinfection
6. Filter Building r
Clearwell.
Mechanical'
z iructural and Failing
Electrical Equipment;and East Cell Clearwell -
CWPS Pump Condition and Cover and Liners
Sizing
r
Combined Storage
and Clz Contact
Filter Capacity and Basins Efficacy
AN ' Condition
I
�� Electrical Power Pipeline and} 3 i! Condition
r Distribution Voltage Supports
k s and Reliability
Water Quality and
Hydraulic Bottleneck
Filter Building into Forebays
Condition and Code • -
Upgrades
4 �Sr
r�Ylr
r
Electrical Equipment;and
- AWPS Pump Condition and
Sizing
2
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KEY FINDING #1 : ELECTRICAL POWER DISTRIBUTION
• Equipment is at the end of its service
life
• Medium voltage (2400V) power is
outdated, inefficient and unnecessary
for the motor sizes needed for current
and future demands
• System is widely distributed when it
could be consolidated and centralized
to meet current and future needs
Condition and improve arc flash
potential of electrical gears increase
safety risk to electricians
5
KEY FINDING #1 : MOTOR CONTROL CENTERS
• Equipment is at the end of its service
life
• MCCs for Filter Plant are outdated and --
parts are no longer available from =__
original equipment manufacturer --
• MCCs for PS are outdoors and =
unprotected, reducing reliability and
making maintenance difficult in =-
inclement weather
• Medium voltage (2400V) power is
outdated, inefficient and unnecessary
for the motor sizes needed for current
and future demands
• Arc flash protection is a significant
concern that must be remedied
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IMPROVEMENT#1: PROPOSED ELECTRICAL UPGRADES
Electrical Upgrades .'
a
• Upgrade/Replace
Electrical Gear at CWPS
• Replace 2,400V Motors
with 480V
Add one UW Pump
• Replace Substation 40West East-
Replace electrical
conductors CW CW
• Replace Filter MCCs
New AW Electrical Feed
Retire Existing Electrical
PS `
t {
■ 7
KEY FINDING #2: STRUCTURE 9000 AND FOREBAYS
Structure 9000:
• Significant seismic deficiencies
of structure
Forebays:
• Requires throttling of plant
effluent pipeline under low flowi.
conditions which carries some
inherent risk
• Not needed for applied water
flow equalization .A-
Degrades applied water quality _
through algae growth and water a
fowl contamination
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Improvement #2: Decouple Forebays and Install a
New AWPS and Associated Electrical Upgrades
' CWPS
:
UW { Zone l RW i
1
' � 1
BW
New AW PS
1 Clea wells
Sub 40 i
Decouple Filter
Forebays and 1
Abandoned chem
Old AWPS �-- FDS(Structure 9000)FE Pipeline
ALVP5 Plant Outfall
(Secondary Effluent) Structura
Forebays
�r Improvements
Re uired
_ / 9
•
Improvement #2: Decouple Forebays and Install a
New AWPS and Associated Electrical Upgrades
-7,
oClearwelis
New AW PS
- _ a
ilters��"
Decouple
Forebays and
Abandoned J
1. .Forebays Structural
Old AWPS 1P
PWPS Improvements
�_ Required to
,ter` Structure 9000
�M• r
w X. ` to
5
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KEY FINDING #3: FILTERS F
• Production capacity is limited
• Filter media and underdrains need
rehabilitation
• Filter underdrain design is outdated and -
subject to upsets of the gravel layer which
must be rebuilt to correct
• High solids loading produces short-filter runs
requiring frequent backwashes and limits
production capacity
• Filter effluent piping and control valves are
undersized for anticipated RW demand
Future demands will not be served with batch
operation.Will require continuous operation
and better automation and control
rCENTRALSAN
IMPROVEMENT #3: FILTERS RECOMMENDED IMPROVEMENTS
• Recommend new underdrains
without gravel
• Recommend new Filter media
• Only two filters need rehabilitation to
meet Phase A capacity
• Rehabilitate two other filters for
Phase B
• Replace control valves and piping
• Upgrade chemical conditioning
• Improve supervisory control and data
acquisition (SCADA) and automation
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KEY FINDING #4: CLEARWELL
• Clearwell cover and liner leaking
• Single cell operational: Maintenance _
very difficult
• Seismic deficiencies for center divider
wall
• Liner and cover are at the end of their
useful lives
• No redundancy to allow shutdown for
cleaning, maintenance and repairs
• Floating cover is a continuous
maintenance
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IMPROVEMENT #4: CLEARWELL RECOMMENDED IMPROVEMENTS
• Recommend replacement of liners (both
east and west cells with a new liner)
• Dewater, clean, and dispose solids in East
Cell -
• Install a new cover on the East Cell
• Replace or repair gates and actuators to
allow for operations of both cells
• Divider Wall and Overflow Structure
Structural Improvements
• Filter Effluent Pipeline Improvements
• Construct 1 million gallon Steel Storage
Tank
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KEY FINDING #5: DISINFECTION
• Variable volume complicates CT
compliance and monitoring
• Without a fixed volume for CT, the
operation is inefficient
• No redundant facilities available to
facilitate shut down for maintenance and
repair
• Effective contact time is 4% of Clearwell
volume due to short-circuiting
• Varying volume of Clearwell
incompatible with fixed volume desired
for disinfection
Membrane cover over Clearwell
prevents access for inspection, cleaning,
and service
16
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IMPROVEMENT #5: DISINFECTION RECOMMENDED IMPROVEMENTS
• Decouple disinfection from R.r
Clearwell Storage y
• Dedicated Chlorine Contact Basin --
(CCB) recommended in CWMP
Y
• CCB more cost effective than UV
disinfection
• Recommend dedicated CCB within
RWP site
• Two CCBs in Phase A i
• Two Additional CCBs in Phase B
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KEY FINDING #6: FILTER
BUILDING
• Update building to current
standards and building codes:
Structural, Lighting, Plumbing s kJ
and HVAC
• Some hazardous materials
(lead and asbestos) abatement
Improvement#6: Implement
Recommended Improvements to
filter Building
,7
PROJECT PRIORITIZATION AND PHASING
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INITIAL PHASED PROJECT APPROACH
Phase 1: (Estimated at$53 M)
• Replace electrical service and distribution (2,400V to 480V)
• Rehab Filter Diversion Structure (or Provide an alternative new
Structure)
• New AWPS (decouple Forebay, eliminate throttling)
• Filter rehabilitation (two out of four minimum)
• Upgrade chemical conditioning
• Upgrade Filter controls
• Perform Clearwell (East and West) Recommended
Improvements
• Chlorine Contact Basins (two out of four)
Phase 2: When CCRP: (Estimated at$35 M)
• Provide booster pumps and additional storage for CCRP project
on site, if needed
• Upgrade remaining two filters
• Chlorine Contact Basins (two additional CCBs)
CENTRAL SAN
PROPOSED PHASE
RECYCLED WATER PLANT FACILITIES IMPROVEMENTS
• Add UW Pump
• Replace BW Motors(480V)
• New 1 MG Storage Tank
• Clearwell:
• Rehab East Clearwell
• Seismic Pining of
divider wall
• New Isolation Gates
• Chlorine Contact Basins
(CCBs)
Rehab two Filters
Upgrade Chemical Feed
• New AWPS(Decouples
Forebays)
Retire Forebays Upgrade/Replace Electrical
Retire Existing AWP Gear
New CW Electrical Facility
Replace Substation 40
Rehab FDS(Structure 9000) New Filter MCCs
• New AWPS Electrical Facility
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TOTAL PROJECT COST
(PHASE 1
Project Cast Est.
Implementation Items Description (In Millions-2019)
1 Electrical Upgrades $ 8.70
Hydraulic Improvements
2 WPS $ 9.40
3 Filter Improvements $ 5.50
4 Clearwell Improvements $ 7.70
5 Disinfection Improvements $ 8.50
6 Filter Building Rehabilitation$ 1.00
Subtotal Phase A $ 40.80
Other Project Cost $ 12.00
Total Project Costgig— 52.80
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PROPOSED FUTURE PHASE 2
RECYCLED WATER PLANT FACILITIES IMPROVEMENTS
Add Booster Pumps
For CCRP
Add Chlorine Contact Ba ins
(CCBs)
Rehab Remaining Filters
r l •1, i'��6P.r'iii
!j
RC
h�r
= New Electrical Gears for
CCRP Booster Pumps
• Upgrade Substation 40
• New Filter MCCs
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FUTURE PHASE 113
RECYCLED WATER PLANT FACILITIES IMPROVEMENTS
Clearwell:
I Z!!fthab East Clearwell
(Hexagon Floats as
West CW)
• Seismic Pining of
divider wall
• New Isolation Gates West East
Chlorine Contact Basins CW CW
(CCBs)
Rehab Filters
Upgrade Chemical Feed
• New AWPS(Decouples - -
Forebays) -
__ Upgrade/Replace Electrical
Retire Forebays .j Gear
Retire Existing AWPS - ,4 New CW Electrical Facility
Replace Substation 40
• New Filter MCCs
• Rehab FDS(Structure 9000)/ New AWPS Electrical Facility
23
06. CENTRAL SAN
REW CAPACITY DEMAND ANALYSIS
24
VNIM
12
May 2, 2019 Regular Board Meeting Agenda Packet- Page 125 of 194
Page 28 of 29
PLANNING FOR THE FUTURE
SHORT-AND LONG-TERM RECYCLED WATER DEMAND ANALYSIS
r _
With Water Exch.(34 MGD)
30 ReW with Nutrient
Removal and Lower
TDS
for Refineries
20 Phase B (19 MGD)
O
Future Peak
11.6-14.4 MGD Daily Q
10
3.8-7.1 MGD
0 -
Base Load with Concord with Water
Demand Community Exchange Future Peak
Reuse Project Project Daily Q
a_ (CCRP)
25
CENTRAL SAN
Recycled Water Demands
.—,athon
I
Shell '.L,=
I I
-Lower Total I I Demands are based on 2009
Dissolved L — — — — — i study
Solids Facility sized for 19 MGD AA
-Lower but could deliver up to 25
Ammonia MGD if available
• There is insufficient supply to
meet peak demands under
.i Notes:
MM and MD peaking factors are assumed current conditions
and based on 2009 report by Paul Puckorius
26
13
May 2, 2019 Regular Board Meeting Agenda Packet- Page 126 of 194
Page 29 of 29
PLANNING FOR WATER EXCHANGE PROPOSED FACILITIES DOESN'T DIRECTLY
IMPACT THE FILTER AND CLEARWELL IMPROVEMENT PROJECT
•ice 6
d7111 MT,16
i
a
27
CENTRAL SAN
14
May 2, 2019 Regular Board Meeting Agenda Packet- Page 127 of 194