HomeMy WebLinkAbout04.a. Draft Position Paper to Authorize GM to Execute Prof Engineering Agreement with Hazen and Sawyer in an Amount NTE $2,000,000 to Complete Final Design Services for Secondary Clarifier & Channel Impr. DP 100047 & is exempt from CEQAPage 1 of 10
Item 4.a.
DCENTRALSAN
MEETING DATE: FEBRUARY7, 2024
BOARD OF DIRECTORS
POSITION PAPER
DRAFT
SUBJECT: REVIEW DRAFT POSITION PAPER TO AUTHORIZE THE GENERAL
MANAGER TO EXECUTE A PROFESSIONAL ENGINEERING SERVICES
AGREEMENT WITH HAZEN AND SAWYER IN AN AMOUNT NOT TO
EXCEED $2,000,000 TO COMPLETE FINAL DESIGN SERVICES FOR THE
SECONDARY CLARIFIER AND CHANNEL IMPROVEMENTS, DISTRICT
PROJECT 100047 (PROJECT);AND FIND THE PROJECT IS EXEMPT
FROM THE CALIFORNIA ENVIRONMENTAL QUALITYACT (CEQA)
SUBMITTED BY: INITIATING DEPARTMENT:
MICHAEL CUNNINGHAM, ASSOCIATE OPERATIONS -PLANT OPERATIONS -
ENGINEER PROCESS CONTROL
REVIEWED BY: NITIN GOEL, OPERATIONS OPTIMIZATION DIVISION MANAGER
GREG NORBY, DEPUTY GENERAL MANAGER - OPERATIONS
ROGER S. BAILEY, GENERAL MANAGER
ISSUE
The Board of Directors' (Board) authorization is required for the General Manager to execute professional
engineering services agreements in an amount greater than $200,000.
BACKGROUND
Central San's secondary process is essential for maintaining National Pollutant Discharge Elimination
System regulatory compliance. The secondary process has three main areas: aeration blowers which
supply air to activated sludge, aeration tanks where activated sludge consumes organic pollutants to
improve water quality, and secondary clarifiers where activated sludge is separated from secondary
effluent and recycled to aeration tanks as returned activated sludge. Secondary effluent is conveyed to
ultraviolet (UV) disinfection before being discharged to Suisun Bay or further treated for recycled water
use.
The Steam and Aeration Blower Systems Renovations, District Project (DP) 7349 (Steam Project)
completed condition assessments and comprehensive asset evaluations of the secondary process. The
findings from these evaluations are being addressed in subsequent capital projects.
February 7, 2024 EOPS Regular Committee Meeting Agenda Packet - Page 10 of 60
Page 2 of 10
One overarching goal is to evaluate potential nutrient removal during design to avoid stranded assets if
Central San were required to meet future nutrient limits.
The recently completed Treatment Plant Piping Renovation - Phase 10, DP 7369 addressed immediate
needs on secondary clarifiers by replacing inlet gates and failed scum piping in clarifier feed channels. The
Electric Blower Improvements, DP 100015 (construction nearing completion) is adding electric blowers to
provide full redundancy to the existing steam blowers. The Aeration Basins Diffuser Replacement and
Seismic Upgrades - Phase 1, DP 100019 (in construction) will replace diffusers and complete mechanical
rehabilitation/replacement, concrete repairs, seismic upgrades, and structural repairs. The Secondary
Clarifier and Channel Improvements, DP 100047 (Project) will extend the remaining useful life of the
secondary clarifiers and feed/effluent channels by addressing aging infrastructure challenges identified in
the Steam Project. Furthermore, the Project will evaluate opportunities to improve resiliency, evaluate
potential nutrient removal opportunities during design to avoid stranded assets in the future, and optimize
performance and hydraulic capacity.
The secondary clarifiers were built during the Stage 5A of the Treatment Plant Expansion, DP X3760 in
1973 and last rehabilitated as part of the Secondary Clarifier Improvements, DP 7089 in 1998. The
clarifier drives, which slowly rotate pipes to collect returned activated sludge at the bottom of the clarifier,
have wearable components that require the equipment to be rebuilt or replaced every 20 to 30 years. The
measurements taken annually during preventative maintenance work suggest that the drives need to be
rebuilt or replaced in the near -term or continued operation could impact performance. This Project will
rebuild or replace clarifier drives, repair concrete and coatings, replace drain gates and scum piping, etc.
Additionally, the feed and effluent channels to each set of four clarifiers will be inspected and rehabilitated.
Hazen and Sawyer will complete the following evaluations to identify opportunities for improvements and
optimizations before completing the final design:
Clarifier hydraulics and process optimization to develop options to improve the efficiency and
maximize the hydraulic capacity of existing clarifiers. The overall goal is to match the wet weather
capacity of the new UV process (140 million gallons per day). UV Disinfection Replacement and
Hydraulic I mprovements, DP 100012 is in final design. Models developed for the evaluation will also
assist with clarifier shutdowns required during inspection. To avoid stranded assets, potential
upgrades will also be modeled under a scenario where Central San removes nutrients.
• Split treatment evaluation to determine the role of existing clarifiers if Central San installs nutrient
removal infrastructure in the existing UV channels after the completion of the new UV process.
• Equipment and resiliency evaluations to compare options for improving the seismic resiliency of
clarifiers and upgrades to improve maintenance staff access to equipment.
Consultant Selection:
On September 28, 2023, a request for proposal was publicly advertised and two consulting firms
responded with proposals. After evaluating the proposals based on qualifications and scope, staff invited
both the consulting firms to participate in interviews on November 30, 2023. The two consulting firms were
Carollo Engineers and Hazen and Sawyer. After the conclusion of the interviews, Hazen and Sawyer was
selected and scored as the top proposer and is, therefore, recommended for the Project.
Project Tasks:
1. Complete evaluations prior to the final design for hydraulic capacity, process optimization, split
stream, and equipment/resiliency improvements. These evaluations will develop a strategy to
optimize performance and avoid stranded assets if Central San is required to remove nutrients.
February 7, 2024 EOPS Regular Committee Meeting Agenda Packet - Page 11 of 60
Page 3 of 10
2. Final design will address aging infrastructure challenges, improve reliability, and extend the useful life
of high value assets. It may also include improvements identified in the evaluations.
California Environmental Quality Act (CEQA)
Staff has concluded that this Project is exempt from CEQA under Section 15262 of Central San's CEQA
Guidelines, since it allows 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
1. The Board may elect to postpone the Project to a future fiscal year. However, this is not
recommended as various components of the secondary clarifier equipment require rehabilitation or
replacement. This alternative would delay opportunities to rehabilitate equipment to extend the useful
life. This alternative is not recommended.
2. The Board may elect to only perform rehabilitation and repair and not evaluations or optimizations
prior to the final design. This alternative may lead to a missed opportunity to improve clarifier capacity
and performance during rehabilitation and replacement and could lead to stranded assets if Central
San were required to remove nutrients. Therefore, this alternative is not recommended.
FINANCIAL IMPACTS
The total estimated cost for the final design for the Project is $2,300,000 which includes consultant
services for $2,000,000, staff time, and contingency. Engineering services during construction is not
currently budgeted under this agreement. Central San will negotiate the engineering services during
construction services with Hazen and Sawyer when the Project is awarded and request approval from the
Board as the Project progresses. The total estimated project cost listed in the budget book is
$10,000,000 and will likely increase as clarifier feed and effluent channels have been added to the Project
scope along with potential hydraulic capacity, process efficiency, and seismic resiliency improvements.
There are adequate funds within the current budget and future budget for the final design of this Project.
COMMITTEE RECOMMENDATION
The Engineering and Operations Committee reviewed this matter at its meeting on February 7, 2024 and
recommended
RECOMMENDED BOARD ACTION
Staff recommends the following Board actions:
1. Authorize the General Manager to execute a professional engineering services agreement with Hazen and
Sawyer in an amount not to exceed $2,000,000 for the final design services for the Secondary Clarifier
and Channel Improvements, District Project 100047; and
2. Find that the project is exempt from CEQA.
February 7, 2024 EOPS Regular Committee Meeting Agenda Packet - Page 12 of 60
Page 4 of 10
Strategic Plan Tie -In
GOAL TWO: Environmental Stewardship
Strategy 1 - Achieve compliance in all regulations
GOAL SIX. Infrastructure Reliability
Strategy 1 - Manage assets optimally, Strategy 2 - Execute long-term capital renewal and replacement program
GOAL SEVEN: Innovation and Agility
Strategy 2 - Implement organization -wide optimization
ATTACHMENTS:
1. Presentation
February 7, 2024 EOPS Regular Committee Meeting Agenda Packet - Page 13 of 60
Page 5 of 10
ATTACHMENT 1
Project Background
Central San's secondary process is essential for
maintaining regulatory compliance.
The secondary process includes blowers which supply air
to activated sludge, aeration tanks where activated
sludge consumes organic pollutants, and secondary
clarifiers where activated sludge is separated from
secondary effluent.
IWOO
Condition assessments completed as part of the Steam
and Aeration Blower Systems Renovations, District
0,
Project (DP) 7349 were addressed in the Electric Blower
Improvements, DP 100015 Aeration Basins Diffuser
ft
and
$
;
Replacement and Seismic Upgrades - Phase 1, DP100019.;;
�r
The Secondary Clarifier and Channel Improvements, DP
V"
100047 (Project) addresses important repairs that were
e.
.•
sequenced to be after the completion of the blower and
aeration tank projects
February 7, 2024 EOPS Regular Committee Meeting Agenda Packet - Page 14 of 60 1
Page 6 of 10
Secondary Clarifier Aging Infrastructure
The secondary clarifiers were built in
1973 and last rehabilitated in 1998. r �
Clarifier drives have wearable
components and require rebuilding or i
r.'.h ....w,
replacing every 20 to 30 years.
This work requires a capital project as
drives and walkway are removed from
the center column. Metal coatings,
concrete repairs, drain gate
replacement, and other miscellaneous
items will also be addressed.
Optimization Evaluations
To Improve Performance and to Avoid Stranded Assets if
Nutrient Removal is Required
• Increase wet weather
capacity
• Improve performance
such as clarifier effluent
clarity
• Improve seismic
resiliency
• Improve safety with
better maintenance
staff access to
equipment
• Plan role of clarifiers if
Central San install
nutrient removal
infrastructure in the
existing UV channels
after the completion of
the new UV process
February 7, 2024 EOPS Regular Committee Meeting Agenda Packet - Page 15 of 60 2
Page 7 of 10
Secondary Clarifiers and Feed/Effluent
Channels
Both North and South Clarifier
feed channels are stacked on
top of the clarifier effluent
channels.
This Project will take both
influent and effluent channels
out of service to complete
condition assessments and
rehabilitated.
Consultant Selection
Two proposals received: Carollo Engineers
and Hazen and Sawyer
Both firms were interviewed on
November 30, 2023
Hazen and Sawyer was selected and
scored as the as top proposer and is,
therefore, recommended for the Project
February 7, 2024 EOPS Regular Committee Meeting Agenda Packet - Page 16 of 60 3
Page 8 of 10
Project Schedule
Notice to Proceed: February 2024 t
Evaluation and Final Design: February—
November 2024 f
Engineering Services during
Construction: To Be Determined
Financial Impacts
The total estimated cost for final design for the Project is $2,300,000, which includes
consultant services for $2,000,000, staff time, and contingency.
Engineering services during construction are not currently budgeted under this
agreement. Central San will negotiate those services with Hazen and Sawyer and
request approval from the Board as the Project progresses.
The total estimated project cost listed in the budget book is $10,000,000 and will likely
increase as clarifier feed and effluent channels have been added to the Project scope
along with potential hydraulic capacity, process efficiency, and seismic resiliency
improvements. The placeholder cost will be updated after final design.
February 7, 2024 EOPS Regular Committee Meeting Agenda Packet - Page 17 of 60 4
Page 9 of 10
Alternatives/Considerations
The Board may elect to postpone the Project to a future fiscal year. However, this is not
recommended as various components of the secondary clarifier equipment require
rehabilitation or replacement. This alternative would delay opportunities to rehabilitate
equipment to extend the useful life. This alternative is not recommended.
The Board may elect to only perform rehabilitation and repair and not evaluations or
optimizations prior to the final design. This alternative may lead to a missed opportunity to
improve clarifier capacity and performance during rehabilitation and replacement and could
lead to stranded assets if Central San were required to remove nutrients. Therefore, this
alternative is not recommended.
Recommended Board Action
Staff recommends the Board authorize the General Manager to execute a professional
engineering services agreement with Hazen and Sawyer in an amount not to exceed
$2,000,000 to complete the final design services for the Secondary Clarifier and
Channel Improvements, District Project 100047.
February 7, 2024 EOPS Regular Committee Meeting Agenda Packet - Page 18 of 60 5
Page 10 of 10
February 7, 2024 EOPS Regular Committee Meeting Agenda Packet - Page 19 of 60 6