Agenda packet — Tulare City Council, March 3, 2026

City of Tulare Page 1 of 3
Tulare Public Library & Council Chamber Tuesday, March 3, 2026 491 North M Street, Tulare CA 93274 5:30 p.m. Regular Meeting www.tulare.ca.gov
Mission Statement
To promote a quality of life making Tulare the most desirable community in which to live, learn, play, work, worship and prosper.

Regular City Council meetings are held on the first and third Tuesdays of each month at the Council Chamber, located inside the Tulare Public Library, 491 North M Street, Tulare. Meetings are subject to cancellation. Additional meetings may be scheduled as needed.

Public Access and Participation
Meetings are open to the public and may be attended in person or viewed live online via the City of Tulare’s YouTube Channel. To provide public comment remotely, please call (559) 366-1849 during the designated Public Comment period. Note: There is a 20-second broadcast delay. If calling in, mute your viewing device to avoid feedback.

Public Comment Guidelines
Members of the public may address the City Council on matters within the jurisdiction of the City of Tulare.

Those wishing to speak are encouraged to complete a Public Comment Card and submit it to the City Clerk prior to the start of the meeting.
• Comments are limited to three minutes per speaker, unless otherwise extended by the Council. • At the start of any agenda item, the mayor may limit the number of speakers or the time allotted per comment, depending on the number of participants and length of the agenda. • When called upon by the mayor, please approach the lectern, state your name and city of residence, and begin your comments.

Rules of Conduct
To maintain order and decorum, the following rules apply:
• All remarks must be directed to the City Council as a whole, not to individual members. • Only the Council and the person recognized to speak may engage in discussion unless authorized by the mayor.
• Questions to Councilmembers or City staff must be directed through the mayor. • Comments must remain on topic, except during the general Public Comment period. • Disruptive behavior (e.g., shouting, interrupting, or creating a disturbance) may result in removal from the meeting under Government Code Sections 54954.3 and 54957.95.

Accessibility
In compliance with the Americans with Disabilities Act (ADA), individuals who require modifications, accommodations, or auxiliary aids to participate in this meeting should contact the City Clerk’s Office at (559) 684-4200. Requests made at least 48 hours in advance will help ensure availability.

Additional Information
• Meeting agendas and related documents are available at www.tulare.ca.gov/agendas. • Copies are also available for public inspection at the City Clerk’s Office, City Hall, 411 E. Kern Avenue, Second Floor, during regular business hours.

City Councilmembers
Patrick Isherwood, Mayor
Steve Harrell, Vice Mayor
Jose Sigala
Terry A. Sayre
City Council Meeting Notice & Agenda Dennis A. Mederos
City Council Meeting Agenda Tuesday, March 3, 2026
City of Tulare Page 2 of 3

1. CALL TO ORDER

2. PLEDGE OF ALLEGIANCE AND INVOCATION – Caleb Byron, Director of Teens Ministry of Tulare Community Church, to deliver an invocation.

3. PROCLAMATIONS & RECOGNITIONS

3.1 Proclamation for Women’s History Month – March 2026.

3.2 Recognition for International Women’s Day and Women’s History Month Honorees.

4. PUBLIC COMMENT - Members of the public wishing to comment on any item not appearing on the agenda may address the City Council at this time. State law prevents Council from acting on any matter not on the agenda; however, your comments may be referred to staff for follow up. This is also the time for the public to comment on items listed under the Consent Calendar or to request an item from the Consent Calendar be pulled for discussion purposes. Comments related to Public Hearing and General Business items will be heard at the time those items are discussed. In fairness to all who wish to speak, public comment is limited to a total of fifteen minutes with each speaker allowed three minutes, unless otherwise extended by Council. Please begin your comments by stating your name and providing your city of residence. For those that wish to provide public comment while viewing the meeting online, you may call (559) 366-1849. Please note that there will be approximately a 20-second delay in broadcast for viewers. When calling in, mute the device used for viewing the meeting.

5. COMMUNICATIONS - Communications are to be submitted to the City Manager’s Office ten days prior to a Council meeting to be considered for this section of the agenda. No action will be taken on matters listed under Communications; however, the Council may direct staff to schedule issues raised during Communications for a future meeting.

6. COUNCIL REPORTS AND ITEMS OF INTEREST

7. CONSENT CALENDAR - All matters listed under the Consent Calendar are considered by the Council to be routine and will be enacted in one motion without discussion. If discussion is desired, that item may be removed and considered separately.

7.1 Waive the reading of ordinances and approve reading by title only.

Recommended Action: Approve the reading by title only of all ordinances and that further reading of such ordinances by waived.

7.2 Approval of City Council Meeting Minutes.

Recommended Action: Approve the minutes of the special and/or regular meeting of February 17, 2026. [M. Wilcox]

7.3 Amphitheater Operator Fee Schedule.

Recommended Action: Receive the fee schedule for Spade Entertainment, official operator of the Adventist Health Amphitheater, for private events held at the amphitheater. [C. Orr]

8. PUBLIC HEARING - Comments related to Public Hearing items are limited to three minutes per speaker, for a maximum of thirty minutes per item, unless otherwise extended by Council. For those that wish to provide public comment while viewing the meeting online, you may call (559) 366-1849.

Please note that there will be approximately a 20-second delay in broadcast for viewers. When calling in, mute the device used for viewing the meeting.

8.1 Master Fee Schedule Amendment.

Recommended Action: Adopt a resolution amending the City’s Master Fee Schedule related to Parks and Recreation fees associated with the use of Zumwalt Park. [C. Orr] City Council Meeting Agenda Tuesday, March 3, 2026
City of Tulare Page 3 of 3

9. GENERAL BUSINESS - Comments related to General Business items are limited to three minutes per speaker, for a maximum of thirty minutes per item, unless otherwise extended by Council. For those that wish to provide public comment while viewing the meeting online, you may call (559) 366-1849.

Please note that there will be approximately a 20-second delay in broadcast for viewers. When calling in, mute the device used for viewing the meeting.

9.1 Planning Commission Appointment.

Recommended Action: Appoint one member to the Planning Commission to the vacant seat for a term ending December 31, 2029. [M. Wilcox]

9.2 Domestic Wastewater Treatment Plant Facility Plan Draft Report.

9.3 Funding for the 250th Anniversary Independence Day Event at Zumwalt Park.

9.4 Fiscal Year 2026 General Fund Mid-Year Budget Review.

Recommended Action: Receive a presentation and adopt a resolution approving Fiscal Year 2026 Budget supplemental appropriation requests. [M. Roberts]

10. FUTURE AGENDA ITEMS

10.1 Teens on Board with Youth Commission.

Recommended Action: Direct staff to add to a future agenda or take no action.

Submitted By: Mayor Isherwood

11. STAFF UPDATES

12. RECESS TO CLOSED SESSION TO DISCUSS THE FOLLOWING

12.1 Conference with Legal Counsel - Existing Litigation (Gov. Code § 54956.9(d)(1)) Name of Case: VCU317197 Laborers International Union of North America Local 294 and People of the State of California, Ex Rel. Rob Bonta, Attorney General of the State of California v. City of Tulare

13. RECONVENE FROM CLOSED SESSION

14. CLOSED SESSION REPORT - This is the time for Council to publicly report specified closed session action and the vote taken on those actions, if any.

15. ADJOURNMENT
The next regularly scheduled meeting of the Tulare City Council is Tuesday, March 17, 2026, at 5:30 p.m. in the Council Chamber, 491 North M Street, Tulare.

AFFIDAVIT OF POSTING AGENDA
I hereby certify, in conformance with Government Code Sections 54954.2, this agenda was posted in the kiosk at the front of City Hall, 411 E. Kern Avenue, as well as on the City of Tulare’s website (www.tulare.ca.gov).

POSTED: Friday, February 27, 2026 Melissa Wilcox, Chief Deputy City Clerk Office of the City Manager
411 East Kern, Tulare, CA 93274
559.684.4200 | www.tulare.ca.gov
To: Mayor and City Councilmembers
From: Marc Mondell, City Manager
Subject: March 3, 2026 Agenda Memo
Date: February 27, 2026
Time estimates are provided as part of the Council’s effort to manage its time at Council meetings. Listed times are estimates only and are subject to change at any time, including while the meeting is in progress.

The Council, by consensus, reserves the right to use more or less time on any item, to change the order of items, and/or to continue items to another meeting. Items may be heard before or after the time estimated on the agenda memo. This may occur to best manage the time at a meeting or to adapt to the participation of the public.
5:30 p.m. Regular Meeting

1. CALL TO ORDER

2. PLEDGE OF ALLEGIANCE AND INVOCATION - Caleb Byron, Director of Teens Ministry of Tulare Community Church, to deliver an invocation.

3. PROCLAMATIONS & RECOGNITIONS [Time Estimate: 5:35 p.m.]

3.1 Proclamation for Women’s History Month – March 2026.

3.2 Recognition for International Women’s Day and Women’s History Month Honorees.

5. COMMUNICATIONS - Communications are to be submitted to the City Manager’s Office ten days prior to a Council Meeting to be considered for this section of the agenda. No action will be taken on matters listed under communications; however, the Council may direct staff to schedule issues raised during communications for a future agenda. Public comments will be limited to three minutes per topic unless otherwise extended by Council. [Time Estimate: 6:10 p.m.]

6. COUNCIL REPORTS AND ITEMS OF INTEREST [Time Estimate: 6:10 p.m.] Tulare City Council Meeting Page 2 of 10
Agenda Memo - March 3, 2026

7.1 Waive the reading of ordinances and approve reading by title only.

Recommended Action: Approve the reading by title only of all ordinances and that further reading of such ordinances be waived.

7.2 Approval of City Council Meeting Minutes.

Recommended Action: Approve the minutes of the special and/or regular meeting of February 17, 2026. [M. Wilcox]

7.3 Amphitheater Operator Fee Schedule.

Recommended Action: Receive the fee schedule for Spade Entertainment, official operator of the Adventist Health Amphitheater, for private events held at the amphitheater. [C. Orr] Summary: On February 17, 2026, Council requested a fee schedule for Spade Entertainment services and production for third party events at Adventist Health Amphitheater. Those fees are provided below:

Spade Entertainment Fee Schedule
Rio Production to run live performance $17,000 - $26,000 Production equipment removed and re-installed $5,000
Amphitheater management (event provides own production) $1,500 Spade Entertainment event coordination $3,500
(Fee only includes liability insurance, event management & permits)
Spade Entertainment full event package $5,600 - $6,800
(Includes facility rental fee, liability insurance, security, janitorial & grounds service, and event management and
coordination)
This is being provided for informational purposes only.

Fiscal Impact & Funding Source(s): There is no fiscal impact associated with this action.

Environmental Review: This action does not constitute a “project” pursuant to California Environmental Quality Act (CEQA).

Potential Conflict of Interest: Staff is not aware of any conflicts of interest.

Legal Review: This item does not require legal review.

Public Notice: This item does not require a public hearing and was noticed as part of the agenda.

Alternative Action: 1) Approve with changes; 2) Deny; or 3) Table.

Tulare City Council Meeting Page 3 of 10
Agenda Memo - March 3, 2026

Please note that there will be approximately a 20-second delay in broadcast for viewers. When calling in, mute the device used for viewing the meeting. [Time Estimate: 6:20 p.m.]

8.1 Master Fee Schedule Amendment.

Recommended Action: Adopt a resolution amending the City’s Master Fee Schedule related to Parks and Recreation fees associated with the use of Zumwalt Park. [C. Orr] Summary: On May 17, 2022, the City Council adopted Resolution 2022-18 establishing the City’s Master Fee Schedule. The fees were based on an analysis of City services and the reasonable costs incurred in providing those services.

Since that time, Zumwalt Park has undergone significant revitalization, including the addition of new amenities and improvements that have enhanced its value as a premier event venue. The existing rental fees for Zumwalt Park no longer reflect these improvements and the associated costs of maintenance and operations.

On February 10, 2026, the Parks and Recreation Commission reviewed and unanimously recommended approval of revisions to the Facility Use Fee Schedule for Zumwalt Park. These revisions were developed to ensure fees are equitable, cost-recovering, and consistent with the enhanced amenities provided.

The proposed amendment to the Master Fee Schedule includes the following updates for Zumwalt Park:

Description Unit Fee
Zumwalt Park Special Events - Private Full Day $1,000
Zumwalt Park Special Events - Non-Profit Groups Full Day $750 Note: Half-day rentals for Zumwalt Park have been eliminated due to the complexity and scale of events typically hosted at this venue.

These changes align with the City’s policy to establish fees that reflect the cost of services provided and ensure that fees do not exceed the cost of providing those services.

Fiscal Impact & Funding Source(s): The updated fees will generate additional revenue to offset the increased costs associated with maintaining and operating Zumwalt Park. There is no negative fiscal impact anticipated.

Environmental Review: This action does not constitute a “project” pursuant to California Environmental Quality Act (CEQA).

Potential Conflict of Interest: Staff is not aware of any conflicts of interest.

Legal Review: This item does not require legal review.

Public Notice: A notice of public hearing was published in The Visalia Times Delta on February 20, 2026, which is at least number 10 days prior to the public hearing.

Alternative Action: 1) Approve with changes; 2) Deny; or 3) Table.

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Agenda Memo - March 3, 2026

Please note that there will be approximately a 20-second delay in broadcast for viewers. When calling in, mute the device used for viewing the meeting. [Time Estimate: 6:25 p.m.]

9.1 Planning Commission Appointment.

Recommended Action: Appoint one member to the Planning Commission to the vacant seat for a term ending December 31, 2029. [M. Wilcox]
Summary: Established by the City Charter, the Planning Commission is responsible for decisions related to land use, zoning, subdivisions, and environmental review. The five-member commission is appointed by the City Council, by seat, and meets on the second and fourth Tuesdays of each month at 5:30 p.m. in the Council Chamber.

Due to the resignation of Shauna Guerrero, there is a vacant seat on the Planning Commission.

Since each member is appointed by the City Council by seat and the vacant seat is a Council Seat 1 appointment, Councilmember Sigala will provide a recommendation for appointment which must be approved by majority vote of the Council.

A notice of vacancy was posted and shared on the City’s website and social media platforms on February 3, 2026. From February 3 to the time of this report, staff received 17 new applications. All applications received and eligible have been provided to Council for review along with applications that were on file prior to the notice of vacancy.

To be considered for appointment, applicants must reside within the city limits or the sphere of influence as long as a majority of the members reside within the city limits.

Staff requests that Council review the applications provided and Councilmember Sigala put forward a recommendation for approval by majority vote of the Council.

Fiscal Impact & Funding Source(s): There is no fiscal impact associated with this action.

Environmental Review: This action does not constitute a “project” pursuant to California Environmental Quality Act (CEQA).

Potential Conflict of Interest: Staff is not aware of any conflicts of interest.

Legal Review: This item does not require legal review.

Alternative Action: 1) Approve with changes; 2) Deny; or 3) Table. Delaying appointment may cause quorum issues.

9.2 Domestic Wastewater Treatment Plant Facility Plan Draft Report.

Recommended Action: Receive the Domestic Wastewater Treatment Plant Facility Planning draft report dated February 2026 and a presentation from Carollo Engineers regarding their findings and recommendations. [T. Whitfield]
Summary: On October 17, 2024, the Board of Public Utilities Commissioners (BPU) approved a task amendment with Carollo Engineers to complete a Wastewater Treatment (WWTP) Facilities Plan, Certification of Fiscal Sustainability, and Reuse Feasibility Plan. The scope of the WWTP Facilities Plan was to evaluate the existing WWTP facilities and make Tulare City Council Meeting Page 5 of 10
Agenda Memo - March 3, 2026
recommendations for future projects to increase the efficiency of the treatment process and to provide additional domestic plant capacity via an expansion project.

Carollo has detailed the development of the Facility Plan in the draft report titled “Domestic Wastewater Treatment Plant Facility Plan” which is provided. A presentation will be made to summarize and detail the work discussed in the draft report including: 1) Historical and Projected Flows and Loads Analysis, 2) Condition Assessment Results, 3) Existing Plant Evaluation, and 4) Alternatives Analysis. Also included is a Capital Improvement Plan detailed by risk, project type, and estimated cost.

The BPU received the draft report and presentation at their meeting on February 19, 2026. The Council is receiving the report and presentation as an informational item only. The BPU will adopt the study at a later meeting in March and will be asked to give staff direction to move forward with a design engineer. Per the City Charter, the BPU has the authority to pledge sewer revenues to fund the expansion project and request City Council action for bond issuance.

Fiscal Impact & Funding Source(s): There is no fiscal impact associated with this action.

Environmental Review: This action does not constitute a “project” pursuant to California Environmental Quality Act (CEQA).

Potential Conflict of Interest: Staff is not aware of any conflicts of interest.

Legal Review: This item does not require legal review.

Public Notice: This item does not require a public hearing and was noticed as part of the agenda.

Alternative Action: 1) Approve with changes; 2) Deny; or 3) Table.

9.3 Funding for the 250th Anniversary Independence Day Event at Zumwalt Park.

Recommended Action: Approve a subsidy of $40,000 from the General Fund unassigned fund balance account to subsidize the July 4th 250th Anniversary Independence Day Event at Zumwalt Park Featuring the Sequoia Symphony Orchestra. [C. Orr] Summary: At the February 17, 2026, City Council meeting, the City Council requested a breakdown for the City’s estimated costs, and potential revenues for the Sequoia Symphony to perform at the Adventist Health Amphitheater on July 4, 2026. The estimated costs and potential revenues follow:

Estimated Costs
Production $ (22,500.00)
Symphony $ (15,000.00)
Janitorial $ (1,500.00)
Security $ (1,000.00)
$ (40,000.00)
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Agenda Memo - March 3, 2026
Potential Revenue
Source Cost ea. Qty Total
VIP boxes $ 500.00 18 $ 9,000.00
VIP seats $ 25.00 200 $ 5,000.00
$ 14,000.00
Any bar revenue will be used to cover costs assumed by Spade Entertainment such as catering, hotel, etc. Spade Entertainment will not be charging a fee for their services for this event. The cost for marketing is estimated to be $2,500 and is already included in Spade Entertainment’s budget.

Any sponsorship obtained by Spade Entertainment will be split 50/50 with the City, and any additional sponsorship revenue goes into a fund to cover remaining expenses above VIP ticket sales revenue (if any). All remaining proceeds will be remitted by Spade Entertainment to the City.

Fiscal Impact & Funding Source(s): Reduction in the General Fund unassigned fund balance account.

Environmental Review: This action does not constitute a “project” pursuant to California Environmental Quality Act (CEQA).

Potential Conflict of Interest: Staff is not aware of any conflicts of interest.

Legal Review: This item does not require legal review.

Public Notice: This item does not require a public hearing and was noticed as part of the agenda.

Alternative Action: 1) Approve with changes; 2) Deny; or 3) Table.

9.4 Fiscal Year 2026 General Fund Mid-Year Budget Review.

Recommended Action: Receive a presentation and adopt a resolution approving Fiscal Year 2026 Budget supplemental appropriation requests. [M. Roberts] Summary: This report provides the mid-year status of the combined operating and capital budgets of General Fund, the City’s primary operating fund. The purpose of this report is to review the financial activities of the first half of the current fiscal year, provide projections of revenues and expenditures through the end of the fiscal year, and recommend various budget adjustments.

First Half of Fiscal Year 2026
The adopted fiscal year 2026 budget is balanced with financing sources (revenues, transfers from other funds, and unallocated fund balance) sufficient to meet approved financing uses (expenditures and transfers to other funds). At adoption of the budget, General Fund revenues and transfers in were estimated to equal General Fund expenditures and transfers out. Based on year-to-date actual revenues and expenditures through December 31, 2025, and expected financial activities through year-end, however, expenditures and transfers out are expected to exceed revenues and transfers in, resulting in a reduction in fund balances. The following sections of this report will discuss the fiscal operating results expected to lead to the (net) variance.

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Agenda Memo - March 3, 2026
Revenues
As shown in Table 1 below, fiscal year 2026 General Fund revenues are estimated to be within 1% of budget. This variance of approximately $599,000 is largely attributed to less-thanprojected revenues in utility users’ tax, franchise taxes, cannabis/dispensary tax, and other revenues.

Table 2 compares General Fund revenues as of December 31st for the current and prior fiscal years. During the first six months of fiscal year 2026, total revenues were approximately $29.7 million, which is $1.3 million more than the $28.4 million in revenues received during the first half of fiscal year 2025. The primary drivers of this increase were higher revenues from transactions and use tax, property taxes, and sales and use tax.

Table 1: Fiscal Year-End Revenue Projections

GENERAL FUND

REVENUES
FISCAL YEAR 2026
Revenue Category 1
Projected
Actual
Adjusted
Budget 2
Projected
Balance
%
Variance
Sales & Use Tax $ 15,000,000 $ 14,000,000 $ 1,000,000 7.1% Transactions & Use Tax (Meas. I) 8,350,000 8,300,000 50,000 0.6% Property Taxes 9,473,000 8,993,000 480,000 5.3%
Utility Users Tax 10,750,000 12,200,000 (1,450,000) -11.9% Property Tax in Lieu of VLF 8,500,000 8,500,000 - 0.0%
Transient Occupancy Tax 2,250,000 2,250,000 - 0.0%
Cannabis/Dispensary Tax (Meas. Y) 900,000 1,000,000 (100,000) -10.0% Franchise Taxes 1,600,000 1,790,000 (190,000) -10.6%
Other Revenues 15,848,465 16,236,989 (388,524) -2.4%
Total $ 72,671,475 $ 73,269,989 ($ 598,524) -0.8%
1 Transfer(s) in not included.
2 Adopted budget total, plus budget amendments, encumbrances, & capital projects appropriations carried forward from previous fiscal year(s)
Table 2: Mid-Year Revenue Comparison

GENERAL FUND

REVENUES
AS OF DECEMBER 31ST
Revenue Category 1 FY 26 FY 25 Difference
Sales & Use Tax $ 5,119,273 $ 4,822,746 $ 296,527
Transactions & Use Tax (Meas. I) 2,755,580 2,087,872 667,708 Property Taxes 5,045,744 4,633,658 412,086
Utility Users Tax 2 5,207,024 5,556,481 (349,458)
Property Tax in Lieu of VLF 3 4,309,961 4,001,706 (308,255) Transient Occupancy Tax 746,628 1,079,732 (333,105)
Cannabis/Dispensary Tax (Meas. Y) 203,486 218,196 (14,709) Franchise Taxes 113,098 65,606 47,493
Other Revenues 6,244,345 5,929,947 314,339
Total $ 29,745,139 $ 28,395,943 $ 1,349,195
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Agenda Memo - March 3, 2026
1 Transfer(s) in not included. 3
VLF – vehicle license fees
Expenditures
As reflected in Table 3, General Fund expenditures at year-end are expected to be $2.2 million less than budgeted. This variance is primarily due to vacant positions City-wide. Police and Fire Department vacancies represent the most significant number of vacant positions and resulting cost savings, with ten Police positions and six Firefighter/Paramedic positions vacant for most of the first half of fiscal year 2026. The approximate total cost savings of these sixteen positions is $1.9 million.

As of February 17, 2026, the Police Department has five Police Officer vacancies. Of these, two candidates are currently in the background investigation phase, and three positions are in active recruitment. A typical police officer recruitment takes approximately 16-20 weeks from application submittal to date of hire. This timeline reflects the extensive testing, background investigation, medical, psychological, and academy placement requirements necessary to ensure public safety and organizational integrity.

Council has made police hiring a clear priority, and the City has responded accordingly by maintaining continuous recruitment efforts. While recruitments are ongoing, vacancies continue to occur due to resignations, retirements, and probationary releases, which are common within law enforcement agencies. Turnover within the Police Department is generally higher than in many other municipal classifications due to the physical demands, mental resilience requirements, and rigorous performance standards associated with the profession.

Additionally, during the recruitment process, a significant number of applicants are disqualified during the background phase. This is an expected outcome and reflects the City’s commitment to hiring only the most qualified and suitable candidates to serve the community. As a result, recruitment timelines should be viewed as active, deliberate, and quality-focused, rather than delayed or stagnant.

Table 4 compares General Fund expenditures as of December 31st for fiscal years 2026 and 2025. Key year-over-year variances were anticipated and include $720,000 in personnel costs primarily due to previously negotiated compensation increases across multiple bargaining units; $661,000 for Zumwalt Park operations; $356,000 in homeless services encampment costs; and $270,000 for the TASTE program.

Table 3: Fiscal Year-End Expenditure Projections

GENERAL FUND

EXPENDITURES
FISCAL YEAR 2026
Expenditure Category
Projected
Actual
Adjusted
Budget 1
Projected
Balance
%
Variance
Salaries & Benefits $ 41,566,324 $ 43,477,231 ($ 1,910,907) -4.4% Maintenance & Operations 14,675,038 14,991,995 (316,957) -2.1% Internal Service Charges & Alloc. Costs 11,443,608 11,443,608 - 0.0% Capital Outlay 862,937 862,937 - 0.0%
Debt Service 491,040 491,040 - 0.0%
Capital Improvements - - - 0.0%
Total $ 69,038,947 $ 71,266,811 ($ 2,227,864) -3.1%
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Agenda Memo - March 3, 2026
1 Adopted budget total, plus budget amendments, encumbrances, & capital projects appropriations carried forward from previous fiscal year(s)
Table 4: Mid-Year Expenditure Comparison

GENERAL FUND

EXPENDITURES
AS OF DECEMBER 31ST
Expenditure Category 1 FY 26 FY 25 Difference
Salaries & Benefits $ 23,091,431 $ 22,371,861 $ 719,570 Maintenance & Operations 6,269,896 4,871,548 1,398,348
Internal Service Charges & Alloc. Costs 5,723,363 2,956,830 2,766,433 Capital Improvements - 42,589 (42,589)
Capital Outlay 333,214 - 333,214
Debt Service - - -
Total $ 35,417,904 $ 30,242,828 $ 5,174,976
Transfers In & Out
While technically not revenues and expenditures (and, hence, not shown above), transfers in and out of the General Fund contribute to fund balance increases and decreases, respectively.

Transfers are expected to remain consistent with the adjusted budgeted amount.

Net Impact on Unassigned Fund Balance
As seen in Table 1 above, the General Fund is expected to realize slightly less revenue than budgeted. And Table 3 shows General Fund expenditures are expected to end the year at $2.2 million under budget. Combining current revenue and expenditure projections, along with planned transfers, results in a $1.2 million anticipated use of fund balance. This projection represents an improvement in the anticipated use of fund balance of $1.6 million, compared to the adjusted budget.

GENERAL FUND

IMPACT ON FUND BALANCE RESERVES
FISCAL YEAR 2026
Projected
Adjusted
Budget Balance
Revenues $ 72,671,465 $ 73,269,989 ($ 598,524)
Transfer(s) In 148,370 148,370 -
Total Revenues & Transfer(s) In $ 72,819,835 $ 73,418,359 ($ 598,524) Expenditures * $ 69,038,947 $ 71,266,811 $ 2,227,864
Transfer(s) Out 5,014,667 5,014,667 -
Total Expenditures & Transfer(s) Out $ 74,053,614 $ 76,281,478 $ 2,227,864 Fund Balance Increase/(Use) ($ 1,233,779) ($ 2,863,119) ($ 1,629,339) * For purpose of estimating fund balance impact, all capital improvement project-related transfers assumed to be expended.

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Agenda Memo - March 3, 2026
Supplemental Appropriation Requests
During the mid-year budget review process, Department of Finance staff worked with departments to determine supplemental appropriations (i.e., budget adjustments) needed, based upon expenses not anticipated during the annual budgeting process, one-time priorities, and new initiatives. These are detailed in Exhibit A, which accompanies this staff report. For the General Fund, these supplemental appropriations represent a use of up to $1,181,659 in fund balance, which is not included in the forecasts presented above.

Staff will continue to monitor expenses and provide revised projections where needed.

Fiscal Impact & Funding Source(s): See attached Exhibit A for detail of recommended and requested budget adjustments and totals by fund.

Environmental Review: This action does not constitute a “project” pursuant to California Environmental Quality Act (CEQA).

Potential Conflict of Interest: Staff is not aware of any conflicts of interest.

Legal Review: This item does not require legal review.

Public Notice: This item does not require a public hearing and was noticed as part of the agenda.

Alternative Action: 1) Approve with changes; 2) Deny; or 3) Table. Adopting the proposed midyear adjustments will authorize expenditures deemed necessary by staff to effectively carry out its responsibilities. If City Council does not approve the proposed changes, the budget may be exceeded, and/or staff may be unable to perform their work as effectively as possible.

10. FUTURE AGENDA ITEMS - NONE SUBMITTED [Time Estimate: 8:45 p.m.]

10.1 Teens on Board with Youth Commission.

Recommended Action: Direct staff to add to a future agenda or take no action.

Submitted by: Mayor Isherwood

11. STAFF UPDATES [Time Estimate: 8:50 p.m.]

12. RECESS TO CLOSED SESSION TO DISCUSS THE FOLLOWING [Time Estimate: 8:50 p.m.]

13. RECONVENE FROM CLOSED SESSION [Time Estimate: 9:20 p.m.]

14. CLOSED SESSION REPORT - This is the time for Council to publicly report specified closed session action and the vote taken on those actions, if any.

15. ADJOURNMENT [Time Estimate: 9:20 p.m.]
The next regularly scheduled meeting of the Tulare City Council is Tuesday, March 17, 2026, at 5:30 p.m. in the Council Chamber, 491 North M Street, Tulare.

WHEREAS' March is nationally recognized as Women's History Month, honoring women's contributions to history, culture, and society; and
WHEREAS, women of every race, class, and ethnic background have made historic contributions to the growth and strength of Tulare in countless recorded and unrecorded ways; and WHEREAS, women continue to play a critical economic, cultural, and social role in every sphere of life in Tulare, and have long been at the forefront of movements that advance justice, equality, and progress; and
WHEREAS' this year's theme, "Leading the Change: Women Shaping a Sustainable Future," recognizes the vital leadership of women in addressing the challenges of today and building a future that is environmentally responsible, economically inclusive, and socially equitable; and WHEREAS, women have championed sustainability through innovation, advocacy, and action, working to protect natural resources, promote renewable energy, and create resilient communities for generations to come; and
WHEREAS, despite these contributions, the role of women in shaping a sustainable future has often been overlooked and undervalued, making it essential to highlight their achievements and amplify their voices; and
WHEREAS, the City of Tulare is proud to honor the stories, history, and leadership of women in our community and throughout our state and nation, and reaffirms its commitment to gender equity, representation, and opportunity for allwomen and girls.

NOW, THEREFORE, we, the City Council of the City of Tulare, do hereby proclaim the month of March 2026 as
Women's History Month
in the City of Tulare and encourage our citizens to celebrate the achievements of women who are leading the change and shaping a sustainable future, and to join in Dated this 3'd day of March 2026.
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City of Tulare Page 1 of 4

CITY OF TULARE

CITY COUNCIL MEETING MINUTES
Tulare Public Library & Council Chamber
491 North M Street, Tulare
Tuesday, February 17, 2026
5:30 p.m. Regular Meeting
Proper notice of this meeting was given pursuant to Government Code Section 54954.2.

COUNCIL PRESENT: Mayor Patrick Isherwood
Vice Mayor Steve Harrell
Councilmember Jose Sigala
Councilmember Terry A. Sayre
Councilmember Dennis A. Mederos
STAFF PRESENT: City Manager Marc Mondell; City Attorney Mario U. Zamora; Chief Deputy City Clerk Melissa Wilcox; Deputy City Manager/Chief Technology Officer Jason Bowling; Chief Financial Officer Mark Roberts; City Engineer Michael Miller; Public Works Director Trisha Whitfield; Community Services Director Chris Orr; Police Chief Fred Ynclan; Fire Chief Michael Ott; General Services Director Manny Correa; Community Development Director Mario Anaya; Executive Director of Economic Development & Redevelopment Jennifer Gomez; Human Resources Director Janie Venegas

1. CALL TO ORDER
Mayor Isherwood called to order the regular meeting of the Tulare City Council at 5:35 p.m. in the Council Chamber located at 491 North M Street.

2. PLEDGE OF ALLEGIANCE AND INVOCATION
Community Services Director Orr led the Pledge of Allegiance, and an invocation was given by Greg Peterson, Pastor of Sunrise Community Church.

3. PUBLIC COMMENT
David Valdez, Zee Enriquez, and Adrian Hernandez addressed the Council regarding the upcoming wrestling event.

Donnette Carter provided various Chamber of Commerce updates.

4. COMMUNICATIONS
City Manager Marc Mondell advised there were no communications.

5. COUNCIL REPORTS AND ITEMS OF INTEREST
Council reported on recent events and discussed items of interest.

6. CONSENT CALENDAR
Items 6.2, 6.3, and 6.4 were removed from the Consent Calendar.

It was moved by Councilmember Sigala, seconded by Councilmember Mederos, and unanimously carried to approve the items on the Consent Calendar as presented except for item

6.2, 6.3, and 6.4.

Item #: 7.2
Consent
City Council Meeting Minutes Tuesday, February 17, 2026 City of Tulare Page 2 of 4

6.1 Waive the reading of ordinances and approve reading by title only.

Recommended Action: Approve the reading by title only of all ordinances and that further reading of such ordinances be waived.

6.5 Landscape Maintenance Contractor Agreement Extension.

Recommended Action: Authorize the City Manager, or designee, to execute the First Amendment to the Professional Landscape Maintenance Contractor agreement with BrightView Landscape Services, Inc. (Routes A and C); and execute the First Amendment to the Professional Landscape Maintenance Contractor agreement with Perfect Care Landscape & Maintenance (Routes B, D, E, and F). [C. Orr]

ITEM(S) PULLED FROM CONSENT CALENDAR

6.2 Approval of City Council Meeting Minutes.

Recommended Action: Approve the minutes of the special and/or regular meetings of February 3, 2026 and February 6, 2026. [M. Wilcox]
Council Action: Councilmember Mederos pulled this item to note an omission in the meeting minutes from February 6. It was moved by Councilmember Mederos, seconded by Vice Mayor Harrell, and unanimously carried to approve the item as amended to include the following in the February 6, 2026 meeting minutes: “Councilmember Mederos stated he would like to see a groundbreaking occur soon for the International Agri-Center Way extension with the project complete by next year’s World Ag Expo, completion of the traffic signal at West and Prosperity, and completion of the Bella Oaks and Mooney Boulevard project.”

6.3 Second Reading and Adoption of Ordinance 2026-01.

Recommended Action: Adopt Ordinance 2026-01 approving and designating the Tulare Veterans Memorial Building, Hoyt House, T29A Convair Airplane, B-17 Bomber, and F-4 Phantom Jet as City of Tulare Historic-Cultural Landmarks and adding them to the Local Register of Historic-Cultural Landmarks pursuant to Tulare Municipal Code Chapter 10.38. [M. Anaya]
Council Action: Councilmember Mederos pulled this item to clarify that he does not have a potential conflict of interest as stated in the staff report. It was moved by Councilmember Mederos, seconded by Vice Mayor Harrell, and unanimously carried to adopt Ordinance 2026-01 as presented.

6.4 Economic Development Updates.

Recommended Action: Receive an update on economic development activities. [J.

Gomez]
Council Action: Councilmember Sigala pulled this item for a verbal report which was given by Executive Director of Economic Development and Redevelopment Gomez. It was moved by Councilmember Sigala, seconded by Vice Mayor Harrell, and unanimously carried to approve the item as presented.

7. GENERAL BUSINESS

7.1 Consideration of Termination of Agreement with TCCAD.

Recommended Action: Direct staff to proceed with consolidating fire and police dispatch operations at the Tulare Police Department; and authorize the City Manager, at the appropriate time, to issue a 90-day notice of termination of the current agreement with Tulare County Consolidated Ambulance Dispatch (TCCAD) for fire dispatch services.

Presented By: City Manager Mondell
Public Comment: There were no public comments.

Council Action: Questions posed by Council were responded to by staff. Vice Mayor Harrell voiced concern about potential issues with operations when consolidated, City Council Meeting Minutes Tuesday, February 17, 2026 City of Tulare Page 3 of 4
particularly with staff being trained specifically for fire dispatch. It was moved by Councilmember Mederos, seconded by Councilmember Sayre, and unanimously carried to approve the item as presented.

7.2 Revised Emergency Shelter Operator Agreement.

Recommended Action: Review a revised emergency shelter service agreement with Lighthouse Rescue Mission (“LRM”) regarding the City’s emergency shelter project for the term May 1, 2026, through April 30, 2027.

Presented By: General Services Director Correa; City Manager Mondell Public Comment: Jason Bender voiced his disagreement with using taxpayer funds to pay for food to feed the dogs at the shelter. He also expressed his hope that the determination of appropriateness for dogs to reside at the shelter not by breed but by behavior. Steve Celentano expressed concern over insurance coverage.

Council Action: Questions posed by Council were responded to by staff and Renee Soto of the Lighthouse Rescue Mission. This item was informational only; therefore, no action was taken. The revised agreement will be brought for Council approval on March 17, 2026.

7.3 Pension Trust Administration Services.

Recommended Action: Adopt a resolution (1) adopting the Public Agencies PostEmployment Benefits Trust (“Plan”) administered by Public Agency Retirement Services (PARS) to prefund the City's unfunded accrued pension liabilities; (2) appointing the City Manager, or his designee, as Plan Administrator; (3) authorizing the Plan Administrator to execute the documents necessary to implement the Plan; and (4) authorizing the City Manager to execute an agreement with Phase II Systems dba Public Agency Retirement Services and PARS for pension trust administration services for the period February 18, 2026, through December 31, 2028, with up to two additional one-year extensions under the same terms.

Presented By: Chief Financial Officer Roberts
Public Comment: There were no public comments.

Council Action: It was moved by Councilmember Mederos, seconded by Vice Mayor Harrell, and unanimously carried to approve the item as presented.

7.4 Park Special Event Permit Process and Facility Use Fee Schedule.

Recommended Action: Review and adopt the City of Tulare Park Special Event Permit Process Policy and Application; review the proposed Facility Use Fee Schedule; and provide direction to staff regarding reserving the first Saturday of May for a Cinco De Mayo community event at Zumwalt Park.

Presented By: Community Services Director Orr
Public Comment: There were no public comments.

Council Action: Following lengthy discussion, it was moved by Mayor Isherwood, seconded by Councilmember Mederos, and carried 4 to 1 (Councilmember Sigala voted no) to approve the item as presented.

7.5 Request for Funding for July 4th Event.

Recommended Action: Provide direction to staff regarding a 250th Anniversary Independence Day event at Zumwalt Park on July 4, 2026, featuring and subsidizing the Sequoia Symphony Orchestra at either $50,000 with a $10 per ticket admission price or $60,000 with free tickets.

Presented By: Community Services Director Orr; City Manager Mondell Public Comment: There were no public comments.

Council Action: Questions posed by Council were responded to by staff and Todd Speelman of Spade Entertainment. Council requested additional information be brought back, including a budget breakdown with revenue component and other pertinent project details. It was the consensus of Council to table this item to March 3, 2026.

City Council Meeting Minutes Tuesday, February 17, 2026 City of Tulare Page 4 of 4

8. FUTURE AGENDA ITEMS - NONE SUBMITTED

9. STAFF UPDATES
Staff provided updates on department activities.

City Manager Mondell announced that the City received two CPRS awards: the 2025 CPRS Award of Excellence for “City of Tulare Zumwalt Park featuring Adventist Health Amphitheater” in the Park Planning Award of Excellence category and for “Letters to Jack Skellington” in the Outstanding Program category. Mr. Mondell updated the Council on AB 1708 which would establish a clear and equitable pathway for cities to access existing Homeless, Housing Assistance, and Prevention (HHAP) funding while reinforcing accountability and alignment with the state’s homelessness goals. Mr. Mondell also updated the Council on graffiti award program requested by Councilmember Sigala, advising there is already a program outlined in the City’s municipal code and that he considers this issue closed.

10. RECESS TO CLOSED SESSION TO DISCUSS THE FOLLOWING ITEMS

10.1 Conference with Labor Negotiators (Gov. Code § 54957.6) Agency Designated Representatives: City Attorney Zamora, City Manager Mondell, Assistant City Manager Gaffery, Deputy City Manager/Chief Technology Officer Bowling, Human Resources Director Venegas
Employee Organization(s): Tulare Professional Fire Fighter Association - Management and Non-Management
Council recessed to closed session at 8:37 p.m.

11. RECONVENE FROM CLOSED SESSION
Council reconvened from closed session at 9:07 p.m.

12. CLOSED SESSION REPORT
There was no reportable action.

13. ADJOURNMENT
Seeing no further business to discuss, Mayor Isherwood adjourned the regular meeting at 9:07 p.m.

This is to certify that the foregoing is a true and
correct copy of the minutes of the special and/or
regular meeting held on February 17, 2026, as
approved by the Tulare City Council.

Marc Mondell, City Clerk

By Melissa Wilcox, Chief Deputy City Clerk
Staff Report
Meeting: City Council
Date: March 3, 2026
Department: Community Services
Submitted by: Chris Orr, Community Services Director
Agenda Title: Amphitheater Operator Fee Schedule

RECOMMENDED ACTION
Receive the fee schedule for Spade Entertainment, official operator of the Adventist Health Amphitheater, for private events held at the amphitheater.

SUMMARY
On February 17, 2026, Council requested a fee schedule for Spade Entertainment services and production for third party events at Adventist Health Amphitheater. Those fees are provided below:

FISCAL IMPACT & FUNDING SOURCES
There is no fiscal impact associated with this action.

ENVIRONMENTAL REVIEW
This action does not constitute a “project” pursuant to the California Environmental Quality Act (CEQA).

POTENTIAL CONFLICT OF INTEREST
Staff is not aware of any conflicts of interest.

LEGAL REVIEW
This item does not require legal review.

PUBLIC NOTICE
This item does not require a public hearing and was noticed as a part of the agenda.

ALTERNATIVE ACTION

1. Approve with changes

2. Deny

3. Table
Item #: 7.3
Consent

ATTACHMENTS
None
Reviewed/Approved:

Staff Report
Meeting: City Council
Date: March 3, 2026
Department: Community Services
Submitted by: Chris Orr, Community Services Director
Agenda Title: Master Fee Schedule Amendment

RECOMMENDED ACTION
Adopt a resolution amending the City’s Master Fee Schedule related to Parks and Recreation fees associated with the use of Zumwalt Park.

SUMMARY
On May 17, 2022, the City Council adopted Resolution 2022-18 establishing the City’s Master Fee Schedule. The fees were based on an analysis of City services and the reasonable costs incurred in providing those services.

The proposed amendment to the Master Fee Schedule includes the following updates for Zumwalt Park:

These changes align with the City’s policy to establish fees that reflect the cost of services provided and ensure that fees do not exceed the cost of providing those services.

FISCAL IMPACT & FUNDING SOURCES
The updated fees will generate additional revenue to offset the increased costs associated with maintaining and operating Zumwalt Park. There is no negative fiscal impact anticipated.

ENVIRONMENTAL REVIEW
This action does not constitute a “project” pursuant to the California Environmental Quality Act (CEQA).

POTENTIAL CONFLICT OF INTEREST
Staff is not aware of any conflicts of interest.

LEGAL REVIEW
This item does not require legal review.

Item #: 8.1
Public Hearing

PUBLIC NOTICE
A notice of public hearing was published in The Visalia Times Delta on February 20, 2026, which is at least number 10 days prior to the public hearing.

ALTERNATIVE ACTION

1. Approve with changes

2. Deny

3. Table

ATTACHMENTS

1. Resolution
Reviewed/Approved:

RESOLUTION 2026-XXX

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF TULARE

AMENDING THE MASTER FEE SCHEDULE WITH REGARD TO CERTAIN PARKS AND

RECREATION FEES
WHEREAS, it is the general policy of the City of Tulare (“City”) to establish fees that are reflective of the cost of services provided by the City; and
WHEREAS, on May 17, 2022, the City Council adopted Resolution 2022-18 establishing a schedule of fees and charges for City services (“Master Fee Schedule”); and WHEREAS, the fees contained in the Master Fee Schedule are based upon an analysis of City services, the reasonable costs borne by the City for providing those services, the beneficiaries of those services, and the revenues produced by those paying fees and charges for services provided; and WHEREAS, the City desires to update certain Parks and Recreation fees and charges within the current Master Fee Schedule; and
WHEREAS, the fees do not exceed the cost of providing the services; and WHEREAS, pursuant to Government Code Section 66018, the specific fees to be charged for services must be adopted by the City Council, by resolution, after providing notice and holding a public hearing; and
WHEREAS, a public hearing was held as part of a regularly scheduled meeting on March 3, 2026, at 5:30 p.m., in the Tulare Council Chamber located at 491 North M Street, Tulare.

NOW, THEREFORE, BE IT RESOLVED by the City Council of the City of Tulare, as follows:

Section 1. The fees and charges as provided in Exhibit A are hereby adopted and incorporated into the City’s adopted Master Fee Schedule.

Section 2. All resolutions and other actions of the City Council in conflict with the contents of this resolution are hereby repealed.

Section 3. This resolution shall go into full force and effect on May 2, 2026, which is 60 days after adoption.

PASSED, APPROVED, AND ADOPTED by the City Council of the City of Tulare this 3rd day of March 2026, by the following vote:

Ayes:

Noes:

Absent:

Abstain:

Patrick Isherwood, President of the Council
and Ex-Officio Mayor
ATTEST:

Marc Mondell, City Clerk
Resolution 2026-XXX

Page 2 ends

By Melissa Wilcox, Chief Deputy City Clerk
The presence of an electronic signature certifies that the foregoing is a true and correct copy as approved by the Tulare City Council.

Resolution 2026-XXX

Page 3 ends

EXHIBIT A
City of Tulare
Master Fee Schedule
Parks & Recreation Department
Description Unit Notes Fee
General Park Use Fees
Park Special Events - Private Half Day Less than 4 hours - Zumwalt Park, Del Lago Park, Mulcahy Park, Centennial
Park
$350
Park Special Events - Private Full Day 4 or more hours - Zumwalt Park, Del Lago Park, Mulcahy Park, Centennial Park
$550
Zumwalt Park Special Events -
Private
Full Day $1,000
Park Special Events - NonProfit GroupsHalf Day Less than 4 hours - Zumwalt Park, Del Lago Park, Mulcahy Park, Centennial
Park
$200
Park Special Events - NonProfit GroupsFull Day 4 or more hours - Zumwalt Park, Del Lago Park, Mulcahy Park, Centennial Park
$300
Zumwalt Park Special Events -
Non-Profit Groups
Full Day $750
Staff Report
Meeting: City Council
Date: March 3, 2026
Department: City Clerk
Submitted by: Melissa Wilcox, Chief Deputy City Clerk
Agenda Title: Planning Commission Appointment

RECOMMENDED ACTION
Appoint one member to the Planning Commission to the vacant seat for a term ending December 31, 2029.

SUMMARY
Established by the City Charter, the Planning Commission is responsible for decisions related to land use, zoning, subdivisions, and environmental review. The five-member commission is appointed by the City Council, by seat, and meets on the second and fourth Tuesdays of each month at 5:30 p.m. in the Council Chamber.

Due to the resignation of Shauna Guerrero, there is a vacant seat on the Planning Commission. Since each member is appointed by the City Council by seat and the vacant seat is a Council Seat 1 appointment, Councilmember Sigala will provide a recommendation for appointment which must be approved by majority vote of the Council.

To be considered for appointment, applicants must reside within the city limits or the sphere of influence as long as a majority of the members reside within the city limits.

Staff requests that Council review the applications provided and Councilmember Sigala put forward a recommendation for approval by majority vote of the Council.

FISCAL IMPACT & FUNDING SOURCES
There is no fiscal impact associated with this action.

ENVIRONMENTAL REVIEW
This action does not constitute a “project” pursuant to the California Environmental Quality Act (CEQA).

POTENTIAL CONFLICT OF INTEREST
Staff is not aware of any conflicts of interest.

LEGAL REVIEW
This item does not require legal review.

PUBLIC NOTICE
This item does not require a public hearing and was noticed as a part of the agenda.

ALTERNATIVE ACTION

1. Approve with changes

2. Deny
Item #: 9.1
General Business

3. Table
Delaying appointment may cause quorum issues.

ATTACHMENTS

1. Applications
Reviewed/Approved:

Staff Report
Meeting: City Council
Date: March 3, 2026
Department: Public Works - Wastewater
Submitted by: Trisha Whitfield, Public Works Director
Agenda Title: Domestic Wastewater Treatment Plant Facility Plan Draft Report

RECOMMENDED ACTION
Receive the Domestic Wastewater Treatment Plant Facility Planning draft report dated February 2026 and a presentation from Carollo Engineers regarding their findings and recommendations.

SUMMARY
On October 17, 2024, the Board of Public Utilities Commissioners (BPU) approved a task amendment with Carollo Engineers to complete a Wastewater Treatment (WWTP) Facilities Plan, Certification of Fiscal Sustainability, and Reuse Feasibility Plan. The scope of the WWTP Facilities Plan was to evaluate the existing WWTP facilities and make recommendations for future projects to increase the efficiency of the treatment process and to provide additional domestic plant capacity via an expansion project.

Per the City Charter, the BPU has the authority to pledge sewer revenues to fund the expansion project and request City Council action for bond issuance.

FISCAL IMPACT & FUNDING SOURCES
There is no fiscal impact associated with this action.

ENVIRONMENTAL REVIEW
This action does not constitute a “project” pursuant to the California Environmental Quality Act (CEQA).

POTENTIAL CONFLICT OF INTEREST
Staff is not aware of any conflicts of interest.

LEGAL REVIEW
This item does not require legal review.

PUBLIC NOTICE
This item does not require a public hearing and was noticed as a part of the agenda.

ALTERNATIVE ACTION

1. Approve with changes

2. Deny

3. Table
Item #: 9.2
General Business

ATTACHMENTS

1. Carollo – Domestic Wastewater Treatment Plant Facility Plan draft report dated February 2026 Reviewed/Approved:

Domestic Wastewater Treatment Plant Facility Plan
Domestic Wastewater Treatment Plant
Facility Plan
February 2026 / DRAFT
1401 FULTON STREET, SUITE 802 ▪ FRESNO, CALIFORNIA 93721 ▪ P 559-436-6616 Domestic Wastewater Treatment Plant
Facility Plan
February 2026 / DRAFT
This document is released for the purpose of information exchange review and planning only under the authority of John R. Witter, February 11, 2026, CA PE C-88706.

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN i
pw://Carollo/CA/Tulare/203729-000000/03 Reports and Studies/02 Deliverables/Wastewater/Executive Summary/Cover-TOC-ABB-APP.docx Contents

EXECUTIVE SUMMARY
ES.1 6BFlows and Loads Analysis ES-1
ES.1.1 Existing DWWTP Description ES-1
ES.1.2 Historical Flows and Loads ES-4
ES.1.3 Projected Flows and Loads ES-6
ES.2 7BCondition Assessment Results ES-8
ES.2.1 Condition Assessment Methodology ES-8
ES.2.2 Condition Assessment Recommendations ES-9
ES.3 8BExisting Plant Evaluation ES-9
ES.3.1 Special Sampling Campaign ES-9
ES.3.2 Model Development and Calibration ES-10
ES.3.3 Existing Plant Deficiencies ES-10
ES.3.4 DWWTP Plant Capacity ES-12
ES.4 8BAlternatives Evaluation and Results ES-15
ES.4.1 Alternatives Screening ES-15
ES.4.2 Plant Expansion Common Improvements ES-16
ES.4.3 Technology Overview ES-19
ES.4.4 Financial Evaluation ES-19
ES.4.5 Site Visits ES-20
ES.4.6 Recommended Treatment Process ES-20
CHAPTER 1 HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS

1.1 Introduction 1-1

1.2 Background 1-1

1.3 Historical Flows and Loads 1-3

1.4 Projected Flows and Loads 1-11

1.5 Design Basis for Plant Expansion 1-15

1.5.1 Regulatory Considerations 1-15

1.5.2 Design Criteria 1-15
CHAPTER 2 CONDITION ASSESSMENT RESULTS

2.1 Introduction 2-1

2.2 Methodology 2-1

2.3 Condition Assessment Evaluation 2-3

2.3.1 Administration Building 2-3

2.3.2 Influent Pump Station and Headworks 2-3

2.3.3 Primary Sedimentation Basins 2-4

2.3.4 Biofilter Recirculation Wet Well 2-5

2.3.5 Anoxic Basin 2-5

2.3.6 Aeration Basins 2-5

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ii

2.3.7 Blower Building 2-6

2.3.8 Secondary Sedimentation Basins 2-6

2.3.9 Pump Gallery 2-7

2.3.10 Secondary Effluent Pump Station 2-7

2.3.11 Biosolids Building 2-8

2.3.12 Anaerobic Digesters 2-8

2.3.13 Sludge Drying Beds 2-9

2.3.14 Electrical System 2-9

2.4 Recommendations 2-11
CHAPTER 3 EXISTING PLANT EVALUATION

3.1 Introduction 3-1

3.2 Special Sampling Campaign 3-1

3.3 Model Development and Calibration 3-3

3.3.1 Model Configuration 3-3

3.3.2 Influent Characterization 3-4

3.3.3 Model Calibration 3-4

3.4 Existing Plant Deficiencies 3-6

3.5 DWWTP Plant Capacity 3-8

3.5.1 Historical Plant Capacity 3-8

3.5.2 Existing Plant Capacity 3-9
CHAPTER 4 ALTERNATIVES ANALYSIS

4.1 Introduction 4-1

4.2 Alternatives Screening 4-1

4.3 Plant Expansion Common Improvements 4-3

4.3.1 Solids Handling Improvements 4-3

4.3.2 Common Improvement Descriptions and Site Layout 4-4

4.4 Technology Overview 4-8

4.4.1 MLE 4-8

4.4.2 MBR 4-10

4.4.3 Oxidation Ditch 4-12

4.4.4 Comparison of Alternatives 4-14

4.5 Financial Evaluation 4-17

4.5.1 Cost-Estimating Methodology 4-17

4.5.2 Financial Evaluation Results 4-18

4.6 Site Visits 4-23

4.7 Recommended Treatment Process 4-23

4.7.1 Opportunities to Reduce Capital Costs 4-23

4.7.2 Split Flow Phased Implementation 4-26

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN iii
Appendices
APPENDIX 2A CONDITION ASSESSMENT SCORING RESULTS
APPENDIX 2B CONDITION ASSESSMENT PHOTOS
APPENDIX 3A SPECIAL SAMPLING PLAN
APPENDIX 3B OPERATIONAL DATA AND PERFORMANCE GRAPHS
APPENDIX 4A CAPITAL COST
APPENDIX 4B O & M COST
Tables
Table ES.1 Historical Influent Flows, Concentrations, and Loads ES-4 Table ES.2 Tulare DWWTP Wastewater Flow Projections ES-6 Table ES.3 Design Flows and Water Quality for Proposed Expansion ES-8 Table ES.4 Condition Scoring ES-8
Table ES.5 Summary of Recommended Improvements ES-9
Table ES 6 Unit Process Capacity Ratings ES-13
Table ES.7 Plant Expansion Treatment Alternatives ES-15 Table ES.8 Common Improvements ES-16
Table ES.9 Potential Capital Cost Reductions ES-21
Table ES.10 Phase 1 Capital Cost Savings ES-21
Table 1.1 Wastewater Flow and Load Definitions 1-4
Table 1.2 Historical Influent Flows, Concentrations, and Loads 1-4 Table 1.3 Historical Influent Ammonia and TKN Concentrations 1-9 Table 1.4 Tulare DWWTP Wastewater Flow Projections 1-12 Table 1.5 Tulare DWWTP Flow and Load Projections 1-12
Table 1.6 Permitted Discharge Limits(1) 1-15
Table 1.7 Design Flows and Water Quality for Proposed Expansion 1-15 Table 2.1 Condition Assessment Asset Types 2-1
Table 2.2 Condition Scoring 2-2
Table 2.3 Summary of Recommended Improvements 2-12
Table 3.1 Two-Week Wastewater Characterization Sampling Program Data Summary 3-2 Table 3.2 Model Influent Wastewater Fractions 3-4
Table 3.3 Model Calibration Results 3-5
Table 3.4 Unit Process Performance and Capacity Criteria 3-9 Table 3.5 Unit Process Capacity Ratings 3-11
Table 4.1 Plant Expansion Treatment Alternatives 4-2
Table 4.2 Common Improvements 4-5
Table 4.3 Summary of Design Criteria for Secondary Treatment Alternatives 4-15 Table 4.4 Capital Cost Factors 4-17
Table 4.5 O&M Cost Factors 4-18
Table 4.6 Common Improvements Capital Costs 4-19
Table 4.7 Technology Alternatives Capital Project Costs 4-20 Table 4.8 Technology Alternatives O&M Costs 4-21

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN iv
Table 4.9 Technology Alternatives Lifecycle Costs 4-22
Table 4.10 Potential Capital Cost Reductions 4-25
Table 4.11 Phase One Capital Cost Savings 4-26
Figures
Figure ES.1 Tulare DWWTP Existing Process Flow Diagram ES-2 Figure ES.2 Tulare DWWTP Existing Site Layout ES-3
Figure ES.3 Daily Average Influent Flows ES-5
Figure ES.4 Influent TSS and BOD Loads ES-5
Figure ES.5 Influent Ammonia and TKN Loads ES-6
Figure ES.6 Projected Influent DWWTP Flows ES-7
Figure ES.7 DWWTP BioWin Model Configuration ES-10
Figure ES.8 Secondary Treatment System Capacity All Aeration Tanks and Clarifiers in Service ES-14
Figure ES.9 Plant Expansion Proposed Site Layout ES-18
Figure ES.10 Life Cycle Costs – Secondary Treatment Alternatives ES-20 Figure ES.11 Ox Ditch Project Costs Implementation Comparison ES-22 Figure 1.1 Tulare DWWTP Existing Process Flow Diagram 1-2 Figure 1.2 Tulare DWWTP Existing Site Layout 1-3
Figure 1.3 Daily Average Influent Flows 1-6
Figure 1.4 Influent TSS, BOD, and COD Loads 1-7
Figure 1.5 Influent TSS, BOD, and COD Concentrations 1-8 Figure 1.6 Influent Ammonia and TKN Loads 1-10
Figure 1.7 Influent Ammonia and TKN Concentrations 1-11 Figure 1.8 Projected Influent DWWTP Flows 1-14
Figure 3.1 DWWTP BioWin Model Configuration 3-3
Figure 3.2 Secondary Treatment System Capacity All Aeration Tanks and Clarifiers in Service 3-12
Figure 4.1 Solids Handling Process Flow Diagram 4-4
Figure 4.2 Common Improvements Planning Level Site Layout 4-7 Figure 4.3 MLE Alternative Process Flow Diagram 4-8
Figure 4.4 MLE Alternative Site Layout 4-10
Figure 4.5 MBR Alternative Process Flow Diagram 4-11
Figure 4.6 MBR Alternative Site Layout 4-12
Figure 4.7 Oxidation Ditch Process Flow Diagram 4-13
Figure 4.8 Oxidation Ditch Alternative Site Layout 4-14 Figure 4.9 Capital Costs – Common Improvements 4-19
Figure 4.10 Capital Costs – Secondary Treatment Alternatives 4-20 Figure 4.11 Annual O&M Costs – Secondary Treatment Alternatives 4-21 Figure 4.12 Life Cycle Costs – Secondary Treatment Alternatives 4-22 Figure 4.13 Sludge Holding Lagoon Layout 4-25
Figure 4.14 Reduced Scope Common Improvements Capital Costs 4-27

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN v
Abbreviations
AACE Association for the Advancement of Cost Engineering AADF annual average daily flow
AAF average annual flow
ADMM average daily maximum month
ADMMF average daily maximum month flow
ADMML average daily maximum month load
ADW average dry weather
ADWF average dry weather flow
ADWL average dry weather load
BNR biological nutrient removal
BOD biochemical oxygen demand
BOD5 five-day biochemical oxygen demand
BSN basin
Carollo Carollo Engineers
CIP Capital Improvement Plan or Clean-in-Place
CIP capital improvement program
City City of Tulare
CMU concrete masonry unit
COD chemical oxygen demand
DDW Division of Drinking Water
DO demand oxygen
DWWTP Domestic Wastewater Treatment Plant
EI&C instrumentation, and controls
ER electrical room
EUL estimated useful life
Facility Plan Wastewater Treatment Plant Facility Planning and Water Reuse Evaluation Fna Fraction of unbiodegradable soluble COD
FRP fiberglass reinforced plastic
GAL gallon
GBT gravity belt thickener
HOA hand-off-auto
HP horsepower
hr hour
IMLR internal mixed liquor return
ISS inert suspended solids
IWWTP Industrial Wastewater Treatment Plant

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN vi
kV kilovolt
kVA kilovolt-ampere
kW kilowatt
kWh kilowatt hour
lb/d pounds per day
LCC life cycle cost
Master Plans Water, Wastewater, and Storm Drain Master Plans MBR Membrane Bioreactor
MCC motor control center
MDF maximum day flow
MG million gallons
mg/L milligrams per liter
mgd million gallons per day
ML mixed liquor
mL/g milliliters per gram
MLE Modified Ludzack Ettinger
MLR mixed liquor return
MLSS mixed liquor suspended solids
MMF maximum month flow
MOP-8 Manual of Practice No. 8
ND non detect
NEC National Electrical Code
NFPA National Fire Protection Association
NH3 ammonia
NH3-N ammonia nitrogen
No. number
NPV net present value
O&M operations and maintenance
ox ditch oxidation ditch
PC primary clarification
PHF peak hourly flow
PLC programmable logic controller
ppd pounds per day
PS primary sludge
R&R rehabilitation or replacement
RAS return activated sludge
RDT rotary drum thickeners
RWRF Fresno-Clovis Regional Wastewater Reclamation Facility S.U. standard units

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN vii
SAT soil aquifer treatment
sBOD soluble biochemical oxygen demand
SC secondary clarification
SCADA supervisory control and data acquisition
SCE Southern California Edison
SCFM standard cubic feet per minute
sCOD soluble chemical oxygen demand
SIU significant industrial user
SRTs solids retention time(s)
SVI sludge volume index
SWBD switchboard
SWGR switchgear
TKN total Kjeldahl nitrogen
TMP transmembrane pressure
TN total nitrogen
TS total solids
TS WAS thickened waste activated sludge
TSS total suspended solids
TWAS thickened waste activated sludge
UPS uninterruptable power source
V volt
VCP vendor control panel
VE value engineering
VFD variable frequency drive
VSS volatile suspended solids
WAS waste activated sludge
WDR waste discharge requirement
WRF Water Reclamation Facility
WT wet ton
ZN zone

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-1

EXECUTIVE SUMMARY
In August 2024, Carollo Engineers (Carollo) completed the Water, Wastewater, and Storm Drain Master Plans (Master Plans) for the City of Tulare (City). Following this effort, the City initiated this Wastewater Treatment Plant Facility Planning and Water Reuse Evaluation (Facility Plan) to build upon the Master Plans, conduct a detailed evaluation of the Domestic Wastewater Treatment Plant (DWWTP), and address deficiencies related to future capacity needs, treatment performance, and regulatory compliance.

The development of this Facility Plan was a collaborative process between the City and Carollo, which included workshops, site visits, a condition assessment, and ongoing communication. The City provided critical information, insight, and feedback throughout the process, ensuring that the Facility Plan reflects the operational needs and long-term objectives of both the City and the DWWTP. The Water Reuse Evaluation will be submitted as a separate deliverable.

This Facility Plan is organized into a series of chapters, each summarizing key planning parameters and analyses developed to meet the project objectives:
 Chapter 1 “Historical and Projected Flows and Loads Analysis” summarizes historical flows and loads trends and presents recommended influent design criteria for a future DWWTP expansion.  Chapter 2 “Condition Assessment Results” presents findings from the on-site condition assessment of the DWWTP.
 Chapter 3 “Existing Plant Evaluation” summarizes results from the two-week special sampling campaign, describes the process model calibration approach, and evaluates the existing DWWTP treatment capacity.
 Chapter 4 “Alternatives Analysis” presents the results of the alternatives evaluation and provides recommendations for a future plant expansion.

ES.1 6BFlows and Loads Analysis
Chapter 1 presents the findings of the influent flows and loads analysis conducted to assess historical conditions, develop future projections, and establish recommended influent design criteria for future plant needs. This section provides a summary of the key results from that analysis.

ES.1.1 Existing DWWTP Description
The DWWTP currently provides preliminary, primary, and secondary treatment. Figure ES.1 presents the process flow diagram, and Figure ES.2 illustrates the site layout of the existing facilities.

The preliminary treatment system includes influent pumping, bar screening, and grit removal. The primary treatment system consists of four primary sedimentation basins, along with primary sludge (PS) and primary scum pumping. The secondary treatment system includes one anoxic basin, three aeration basins, six rectangular secondary clarifiers, and return activated sludge (RAS) and waste activated sludge (WAS) pumping.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO
CITY OF TULARE DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-2 Figure ES.1 Tulare DWWTP Existing Process Flow Diagram

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO
CITY OF TULARE DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-3 Figure ES.2 Tulare DWWTP Existing Site Layout

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-4
Under normal operating conditions, primary effluent, RAS, and internal mixed liquor return (IMLR) flows combine in the Biofilter Recirculation Wet Well before being pumped to the anoxic basin. Currently, PS is pumped through the digesters and then to the domestic sludge drying beds. However, the digesters are unheated and undersized, resulting in minimal digestion. WAS is diverted to the Industrial Wastewater Treatment Plant (IWWTP) for further processing and disposal. Also, the biofilters are no longer in service, and the gravity thickeners have been offline since 2014.

ES.1.2 Historical Flows and Loads
Six years of data from January 2019 to December 2024 were analyzed to determine the influent flows and loads for a range of conditions (e.g., average dry weather [ADW], average daily maximum month [ADMM], etc.). Table ES.1 summarizes the influent historical data for flow, total suspended solids (TSS), biochemical oxygen demand (BOD), ammonia (NH3), and total Kjeldahl nitrogen (TKN). Figures ES.3 to ES. 5 graphically show the flows and loads for these constituents.

Over the six-year period, influent flow meter data indicates that flows remained relatively stable, as shown in Figure ES.3. However, City staff noted that influent flows above approximately 4 million gallons per day (mgd) lead to poor treatment performance and violations of effluent limits. Therefore, the plant diverts daily peak flows to the IWWTP. Because this bypassed flow is not metered, the actual influent flow to the DWWTP is unknown. Between June 9 and June 23, 2025, the City operated the influent pump station in level mode, sending all flow through the DWWTP without bypassing flow to the IWWTP. During this period, the average influent flow was 4.56 mgd, which is notably higher than the previous six-year ADWF of 3.98 mgd. This adjusted ADWF was incorporated into the future flow projections.

As shown in Figures ES.4 and Figure ES.5, influent loads and concentrations began increasing in 2020, peaked in 2022, and then decreased through the end of 2024. The ratio of peak to average flows also decreased in 2023 and 2024, likely reflecting changes in the volume of flow bypassed to the IWWTP.

Increased bypassing of peak flows can result in artificially low concentration measurements, depending on how the composite influent sampler is programmed. It is estimated that concentration data from 2024 is not representative of true influent characteristics.

Table ES.1 Historical Influent Flows, Concentrations, and Loads Condition 2019-2024 Average
Average Annual
Flow, mgd 4.16
TSS, mg/L 303
BOD, mg/L 319
NH3, mg/L 39
TKN, mg/L 1,350
Max Month Flow, mgd 4.43
Max Day Flow, mgd 5.66
Peak Hour Flow, mgd 9.42
Notes:
mg/L – milligrams per liter, ppd – pounds per day.

EXECUTIVE SUMMARY
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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-5
Figure ES.3 Daily Average Influent Flows
Figure ES.4 Influent TSS and BOD Loads

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-6
Figure ES.5 Influent Ammonia and TKN Loads
ES.1.3 Projected Flows and Loads
Flow projections were initially developed in the sewer master plan completed in 2024, which was based on land use assumptions from the City’s most recent 2035 General Plan (adopted in October 2014). Table ES.2, shown below, summarizes the projected ADWF contributed from the existing, planned developments, and vacant infill.

Table ES.2 Tulare DWWTP Wastewater Flow Projections
Planning Period Projected ADWF (mgd)
Existing ADWF(1) 4.5
Planned Developments(2) 1.1
Vacant Infill(3) 0.9
Total Buildout within City Limits 6.5
Notes:
(1) Based on the data collected by plant staff during the operational period in June 2025 when the plant did not bypass influent flow to the IWWTP.
(2) Assumed all wastewater flows from Planned Developments will contribute to the DWWTP projected influent. (3) Assumed that the “Industrial” land-use category summarized in the previous Wastewater Master Plan would contribute to the IWWTP influent rather than the DWWTP influent. Therefore, the projected ADWF from vacant infill constitutes the wastewater flows from the following land-use categories: single-family residential, multi-family residential, commercial, and public.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-7
The Total Buildout projected ADWF within City Limits for the DWWTP is approximately 6.5 mgd. The projections for the other flow conditions (i.e., average annual, average daily max month, etc.) were determined using peaking factors calculated from the historical data. Peaking factors represent the various flow conditions as the ratio to the ADWF. During WWTP Flows & Loadings Workshop on May 15, 2025, City staff mentioned that some years in the 6-year data analysis window may not be representative of typical plant conditions. Therefore, a three-year data analysis period from January 2021 to December 2023 was deemed representative to conservatively base projected flows and loads calculations.

According to the City’s 2035 General Plan, the annual growth rate is approximately 2.7 percent. At this rate, it is estimated that the City would not exceed the projected buildout influent flows until 2042, which is a planning period of approximately 18 years. Figure ES.6 graphically shows this 2.7 percent annual growth for varying flow conditions until 2042.

Figure ES.6 Projected Influent DWWTP Flows
Future expansions of wastewater treatment plants typically design according to average day max month flow and load conditions. Table ES.3 summarizes the proposed design criteria for a DWWTP plant expansion.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-8
Table ES.3 Design Flows and Water Quality for Proposed Expansion Parameter Proposed Expansion Design Criteria
Influent Flow, mgd ADMM 7
TSS, mg/L 397
BOD, mg/L 402
NH3-N, mg/L 44
TKN, mg/L 52
ES.2 7BCondition Assessment Results
Chapter 2 outlines the methodology and key findings of the DWWTP condition assessment. In June 2025, Carollo conducted an on-site condition assessment of the DWWTP’s critical assets. The results of this assessment were used to identify assets requiring rehabilitation or replacement (R&R) and to prioritize projects for future budget planning. This section summarizes the condition assessment approach and resulting recommendations. For more details and discussion of the condition assessment, refer to Chapter 2.

ES.2.1 Condition Assessment Methodology
The condition assessment was performed by a multi-disciplined team of engineers (mechanical, structural, and electrical) who conducted visual inspections of assets to evaluate their overall conditions based on observed deterioration, corrosion, cracking, and other deficiencies. During the assessment, Carollo also met with City operations and maintenance (O&M) staff to discuss asset performance, reliability, O&M requirements, and equipment obsolescence. Each asset included in the evaluation was assigned a score from 1 to 5 based on its general condition and operational performance.

Table ES.4 summarizes the scoring system used to evaluate the DWWTP’s critical assets. A score of 1 indicates assets in good condition, while scores of 4 or 5 reflect assets requiring near-term R&R. Typically, an asset's condition correlates with the percentage of its useful life consumed. For example, a condition score of 1 typically corresponds to recently installed equipment (less than five years old).

Table ES.4 Condition Scoring
Condition Score General Description Percent Life Consumed 1 (Best) Good: Asset is in good condition (no defects). 0 - 39 2 Acceptable: Asset has minor defects. 40 - 64
3 Fair: Asset has significant defects that will affect reliability or efficiency. 65 - 79 4 Poor: Asset is highly unreliable or inefficient. 80 - 89 5 (Worst) Failed: Asset is no longer able to function in its current condition. 90-100

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-9
ES.2.2 Condition Assessment Recommendations
Table ES.5 lists the recommendations identified from the condition assessment results. These improvements are recommended to be included as part of the plant expansion project.

Table ES.5 Summary of Recommended Improvements
Process Area Recommendation
Administration Building Replace with new building.

Influent Pump Station Put check valves on drain lines going into the wet well.

Primary Sedimentation Basin Recoat basins, replace channel air piping, level weirs, rebuild/replace drive mechanisms.

Anoxic Basin Clean/replace swing zone diffusers.

Aeration Basin Clean/replace diffusers.

Blower Building Replace blowers.

Secondary Sedimentation Basin Recoat basins, level weirs, modify flow split.

Secondary Effluent Pump Station Replace pumps, motors, base plates, and mechanical components, inspect box outlet for blockages, increase capacity to combined effluent box.

Biosolids building Inspect roof, decommission sludge heating units, replace GBT VCP, run GBT to confirm functionality.

Anaerobic Digesters Apply injection grout, recoat tanks, inspect/rehab process piping.

Sludge Drying Beds Asphalt or concrete line beds, rehab/replace decant gates and pumps.

Electrical System Relocate loads from Control Room, conduct short circuit study, update arc flash labels, replace older conduits/ cables, conduct grounding study.

ES.3 8BExisting Plant Evaluation
A wastewater process model of the DWWTP was developed using EnviroSim’s BioWin wastewater treatment simulation software (version 6.3) to evaluate the existing plant. This section summarizes the key findings presented in Chapter 3, including results from the two-week special sampling campaign, BioWin model development and calibration, and capacity assessment of the existing DWWTP. For more details and discussion of the existing plant evaluation, refer to Chapter 3.

ES.3.1 Special Sampling Campaign
A two-week special sampling campaign was conducted to support the BioWin model calibration and provide detailed, plant-specific data for accurate wastewater characterization – data that extends beyond the routine operational samples typically collected at the DWWTP. This two-week special sampling effort took place from January 21, 2025 through February 3, 2025. The resulting dataset, provided by the City, was used to refine the default BioWin characterization fractions and calibrate the influent for the DWWTP process model.

One key observation from the special sampling campaign is that sampling occurred during a period when the plant was not nitrifying and was not consistently meeting several effluent waste discharge requirement (WDR) limits. As a result, some of the wastewater characteristics observed during the sampling period, particularly in the secondary effluent, may not accurately represent the plant’s typical or designed operating conditions.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-10 ES.3.2 Model Development and Calibration
As shown in Figure ES.7, the BioWin model was developed based on the existing DWWTP operations and reflect the unit processes that are actively in service. Physical dimensions (e.g., volume, area, depth) of each unit process and flow rates (e.g., WAS, RAS, influent) were incorporated as model inputs. All dimensions, assumptions, and other applicable model inputs were derived from the original design criteria and discussions with plant staff.

Model calibration involves identifying key parameters and adjusting them so that simulated results closely match the average plant data measured during the calibration period. BioWin wastewater treatment models are typically calibrated using a three-month dataset that reflects stable operating conditions. For the DWWTP model, the selected calibration period was July 1, 2023 through September 30, 2023. A steady-state simulation was then run to complete the calibration process.

Abbreviations: BSN – basin; ZN – zone; MLR – mixed liquor return.

Figure ES.7 DWWTP BioWin Model Configuration
Typically, a calibrated model exhibits an accuracy within a 10 percent margin of the historical calibration period data. The model has good agreement for key parameters, such as MLSS concentration, RAS concentration, and SRT. Also, the influent characteristics, primary effluent flow, secondary effluent flows, and solids production have a good calibration and are within the 10 percent margin. Primary effluent TSS concentration and load, secondary effluent BOD concentration, and secondary effluent nitrogen species concentrations are outside the desired range, however, for the purpose of evaluating treatment facilities in the master plan, the model is calibrated and sufficiently accurate. The discrepancy in these parameters could be due to variability in the process performance or operating conditions causing average values of historical data to not be representative of steady-state conditions. The following section summarizes deficiencies at the plant that could cause the model to overpredict plant performance.

ES.3.3 Existing Plant Deficiencies
During the assessment of the existing DWWTP, it became clear that the plant has significant process deficiencies and operates with substantial variability and inconsistency. Analysis of plant operations data shows fluctuations in treatment performance, and the plant frequently struggles to maintain effluent compliance for BOD, TSS, and total nitrogen. Also, to reduce influent loading, the plant routinely diverts a portion of the influent to the IWWTP.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-11 Because of this operational variability, the BioWin process model matched historical data for many parameters but overpredicted others. These discrepancies are likely due to uncertainties with portions of the historical dataset, combined with hydraulic and process deficiencies that contribute to inconsistent basin performance. As a result, the average values used for model calibration may not accurately reflect true steady-state operating conditions.

The following bullet points summarize process deficiencies at the plant:
 Biofilter recirculation wet well:
» Primary effluent, RAS, and MLR flows combine in the biofilter recirculation wet well, none of which are individually metered. The combined flow is then pumped to the anoxic basin. The combined anoxic basin influent is metered but the flow meter is installed at a high point in the line, which causes errors in the readings.
» The water level in the wet well varies quickly. If the water level in the wet well is too high, it can cause the primary sedimentation basin weirs to become submerged. If the water level is too low, it can cause the RAS pumps to over pump the sludge blanket and create a cone of mixed liquor that short circuits the sludge blanket.
 Anoxic and aerobic basins:
» The plant has a single anoxic basin that cannot be easily bypassed or taken out of service. The basin has not been drained since it came online around 2005. » The anoxic basin diffusers are beyond the end of their useful life, which is likely affecting oxygen transfer efficiency and ability to maintain a (DO) concentration. » A lack of mixers in the swing zones could cause solids to settle and accumulate in the anoxic basin.
» The geometry of the anoxic basin is asymmetrical and does not evenly feed the subsequent three aeration basins, which causes uneven solids inventory and performance across the three basins. » The aeration basins have not been taken offline or drained in several decades and the diffusers are beyond the end of their useful life, which is likely affecting oxygen transfer efficiency and ability to maintain a DO concentration.
» DO data appears skewed and changes abruptly after probes are recalibrated, indicating the DO may actually be lower than what the DO probes are reporting. » Low DO concentrations can contribute to poor settling (high sludge volume index [SVI]) in the sedimentation basins and insufficient oxygen to fully nitrify. » The blowers struggle to provide sufficient flow rates to maintain necessary DO concentrations, particularly during high load events.
» The plant has been operating at higher SRTs and higher MLSS concentrations during the winter to increase nitrification rates. However, based on recent historical data, this operation is still not enough to fully nitrify during the winter, which indicates that the aeration basins do not have sufficient oxygen, bioreactor aeration volume, or both.  Secondary sedimentation basins and sludge pumps:
» The geometry of the mixed liquor channel causes an uneven flow distribution from the aeration basins to the secondary sedimentation basins. The clarifiers are fed through a submerged orifice in the channel that does not easily allow for monitoring and adjusting the feed across each clarifier.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-12 » Uneven flow to the secondary sedimentation basins can disrupt settling, cause short-circuiting, dead zones, increased effluent TSS concentrations, and uneven sludge blanket depths. » Plant staff have observed better sludge blankets in secondary sedimentation basins #5 and #6 compared to the sludge blankets in basins #1-#4 due to their differences in depth (basins #5 and #6 are 13.2 feet deep and basins #1-#4 are 9.5 feet deep). Based on data shared by the City, the secondary treatment process has poor settling, with high SVIs. The average SVI value from the 3- month calibration period was 137 mL/g, and the 90th percentile from the same period was 175 mL/g. The 90th percentile from the 2024 calendar year was 258 mL/g. Poor settling can cause permit violations and can be an indication of other process issues. » Currently there are no flow meters on the WAS or RAS lines. The lack of flow data causes uncertainties in calculating the SRT and makes it more difficult to troubleshoot and adjust setpoints to maintain stable operations.
» The configuration of the RAS and WAS piping causes uneven flow rates from each of the sedimentation basin sludge blankets.

The variable and inconsistent plant performance is likely causing historical average data to not be representative of steady state conditions. Additionally, some uncertainty around the historical data further complicated developing a calibrated model. While the process model matches the influent wastewater characteristics well and is useful to determine future plant sizing and configuration, the lack of stable and consistent historical performance adds uncertainty to the accuracy of the existing plant capacity.

ES.3.4 DWWTP Plant Capacity
In 1996, the plant underwent an expansion that increased the design capacity to 6 mgd. The City completed the DWWTP Advanced Treatment Upgrade in 2006, adding an anoxic basin for nitrogen removal to 10 mg/L or less. In 2010, another upgrade added an influent pump station, headworks screening, and grit removal. Despite these projects, the actual treatment capacity is suspected to be lower than the original rated capacity.

A capacity evaluation completed in 2013, required under the City’s WDR, estimated the plant’s capacity at approximately 5.2 mgd AADF and 5.5 mgd ADMMF. The reduced capacity was attributed to increased influent BOD, TSS, and TKN concentrations, along with limitations in the aeration system, which has not been upgraded since. Following the 2013 study, several operational changes were implemented, including returning the biofilters to service. A subsequent capacity evaluation in 2017 estimated the plant’s capacity at 5.5 mgd AADF and 5.8 mgd ADMMF. Since that time, influent flows have remained relatively stable, but influent BOD and TSS concentrations have increased by approximately 26 percent and 40 percent, respectively (see Chapter 1). In addition, the biofilters are no longer in service, further reducing treatment capacity.

Over the past 15 years, water conservation has slowed or reduced domestic wastewater flows; however, influent concentrations have continued to increase. Based on the high-strength maximum month influent wastewater concentrations presented in Chapter 1, the plant’s flow capacity has likely decreased further relative to the 2013 and 2017 evaluations. Load capacity (e.g., pounds per day of influent BOD, TSS, and TKN), however, remains similar.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-13 The existing secondary treatment capacity was estimated using both state point analysis and the calibrated BioWin model. State point analysis evaluates clarifier capacity based on sludge settling performance, which depends on MLSS concentration and SVI. BioWin was used to assess aeration basin capacity by simulating MLSS concentrations over a range of flow scenarios. Previous evaluations (2013 and 2017) were performed under different influent conditions and when then biofilters were still in service, making them less representative of current operations.

Table ES.6 presents the estimated capacity for each unit process based on the recommended capacity criteria. AAF and PHF capacity is developed for each unit process assuming all units in service. The anoxic basin, aeration basins, and secondary sedimentation basin basins constitute the secondary treatment system and are assigned the same capacities, as these processes are integral to each other and depend on several factors, including SRT, MLSS concentration, SVI, temperature, and flow distribution. The primary sedimentation basins and secondary treatment system do not have sufficient capacity for the plant expansion. The secondary treatment system capacity is lower than the previous design values. One reason is the poor oxygen transfer through the aeration system that results in lower DO concentrations, poor settleability, and higher mixed liquor concentrations, all of which negatively impact capacity. Replacing the diffusers and operating at a higher DO concentration may help recover some capacity.

Table ES 6 Unit Process Capacity Ratings
Process Controlling Condition Capacity, mgd Projected 2043 Flow, mgd
Capacity Deficit, mgd
Influent Pump Station PHF 16 16 0
Screens and Grit
Removal
PHF 16 16 0
Primary Sedimentation
Basins
PHF
AAF

14.7 6.2
16 6.8

1.3 0.6
Secondary Treatment
System(1)
PHF
AAF (Winter)
AAF (Summer)
6 2.5

4.2 16

6.8 6.8
10 4.3

2.6 Notes:

AB - table notes abbreviations; BC - table notes abbreviations (1) Estimated capacity based on max month load conditions, an aSRT of 8 days, temperature of 15 degrees Celsius in winter and an aSRT of 3.5 days and temperature of 25 degrees Celsius in summer, SVI of 150 mL/g, and a PHF/AAF peaking factor of 2.4.

To determine the AAF capacity of the aeration basins, the steady state BioWin process model was used to simulate process conditions under maximum month loading. The model was used to estimate the MLSS concentration over a range of flow and aSRT conditions. Currently, the plant is typically operated at an aSRT of around 4.5 days, which leads to effluent violations and the inability to fully nitrify in the winter. A much longer SRT, around 8 days, is estimated to be needed to reliably meet effluent limitations year round. Simulations for capacity were performed at an 8 day aSRT.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-14 when temperatures are warmer, the plant has more biological capacity to treat maximum month loading conditions due to the need for a shorter aSRT to fully nitrify. The minimum month temperature limits the capacity of the secondary system and represents a worst-case scenario.

The recommended capacity rating for the secondary facilities is 2.5 mgd AAF (6 mgd PHF) during minimum month temperatures and 4.2 mgd AAF (10 mgd PHF) during max month temperatures, which represents the intersection of the 8-day aSRT line and the Secondary Sedimentation Basin capacity line estimated from the SVI of 150 mL/g. If the settleability were degraded, then the capacity would be reduced.

Figure ES.8 Secondary Treatment System Capacity All Aeration Tanks and Clarifiers in Service The existing plant is insufficient for the future capacity needs. Expanding the existing plant would require complex modifications to aging infrastructure, which introduces uncertainty regarding its feasibility and would still not resolve the hydraulic and process deficiencies described previously. Additionally, the space available for future expansion does not allow for symmetrical layout of aeration basin facilities and does not consider feasibility of future expansions. Chapter 4 describes the alternatives that were considered and shortlisted for detailed evaluation to provide the additional plant capacity required.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-15 ES.4 8BAlternatives Evaluation and Results
Chapter 4 presents the alternatives evaluated for the plant expansion and results of that analysis. This section summarizes the approach used to select alternatives for detailed evaluation, along with the methodology, findings, and recommendations. For additional information and details, refer to Chapter 4.

ES.4.1 Alternatives Screening
A preliminary analysis was conducted and identified six potential plant expansion alternatives capable of addressing future capacity needs and existing effluent quality deficiencies. Based on input from the City, three of these alternatives were selected for detailed evaluation to determine the most cost-effective, reliable, and robust plant expansion configuration. Table ES.7 summarizes all proposed alternatives and highlights the three alternatives the City selected for in-depth analysis.

Table ES.7 Plant Expansion Treatment Alternatives
# Alternative Name Description City Feedback (1)
1 Expand Existing
DWWTP
 Construct additional primary clarifiers, aeration basins, and secondary clarifiers, similar to existing.
 Rehab existing boilers, heat exchangers, digesters, and gravity belt thickener.
 Add dewatering, waste gas flare, and thickening
redundancy.

Do not evaluate further.

City has no desire to expand
existing plant. It would not
address fundamental issues with
performance or hydraulics.
2 Convert Existing
DWWTP to MBR
Facility
 Construct additional primary clarifiers, similar to existing.  Convert secondary clarifiers to MBR tanks.
 Rehab existing boilers, heat exchangers, digesters, and gravity belt thickener.
 Add dewatering, waste gas flare, and thickening
redundancy.

Do not evaluate further.

This alternative would be an
improvement but not sufficient in
solving other plant challenges
regarding performance, hydraulic
concerns, risks, and construction
constraints.
3 Greenfield:

PC/MLE
Process/SC
 Construct new primary treatment, secondary treatment, and solids handling systems, including primary clarifiers, bioreactors, secondary clarifiers, digesters, thickening, and dewatering.
 Abandon existing DWWTP liquid stream facilities.

Do not evaluate further.

This alternative would require
high (LCC) and regulatory
requirements in rehabilitating,
maintaining, and expanding the
thickening, digestion, and gas
handling facilities.
4a Greenfield:

Secondary only
(MLE Process)
 Construct new secondary treatment and solids handling systems, including bioreactors, secondary clarifiers, and thickening
 Abandon existing DWWTP liquid stream facilities.

Evaluate in detailed analysis.
4b Greenfield:

Secondary only
(MBR)
 Construct new secondary treatment and solids handling systems, including bioreactors, membrane tanks and
associated ancillary facilities, and thickening.
 Abandon existing DWWTP liquid stream facilities.

Evaluate in detailed analysis.
4c Greenfield:

Secondary only
(Oxidation Ditch)
 Construct new secondary treatment and solids handling systems, including oxidation ditches, secondary clarifiers, and thickening.
 Abandon existing DWWTP liquid stream facilities.

Evaluate in detailed analysis.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-16 Notes:

MBR – Membrane Bioreactor; MLE – Modified Ludzack Ettinger; PC – primary clarification; SC – secondary clarification. (1) Selections from August 20, 2025 workshop based on discussions with City staff.

Through discussion with the City, it was determined that the plant expansion should focus on new greenfield treatment processes and exclude primary treatment, digestion, and gas production. For this alternatives analysis, the new plant expansion was assumed to be sized for full buildout at 7.1 mgd ADMM, with the option for phased implementation depending on future funding availability (as further discussed in Chapter 4).

ES.4.2 Plant Expansion Common Improvements
There are several shared improvements that the DWWTP would need for the plant expansion regardless of the selected treatment alternative. These common improvements are presented separately from the secondary treatment alternatives to highlight the facility’s baseline needs and to focus subsequent discussions purely on the comparative differences of the treatment technologies. Table ES.8 summarizes these common improvements for the plant expansion. Figure ES.9 shows the site layout for these common improvements, including the area where the secondary treatment process would be sited.

Table ES.8 Common Improvements
Improvement Description Considerations/Notes (1)
Admin
Building
Construct new admin building to serve as
a central operations building for the
DWWTP and meet updated space needs,
including plant laboratory, SCADA control
room, workspaces, larger meeting/break
rooms, and other essential support
infrastructure.

City is considering constructing a new Corporation Yard across the street (Northeast of the plant), which may be the preferable location for the new admin building. Per request from the City, a high-level budgetary cost for the admin building is included in the plant expansion total project cost, however, it may fall under a separate City project budget in the future. It is recommended that specific features of the building, including construction material and architectural finish, lab equipment, number and size of offices and
conference rooms, are determined during preliminary design.

Electrical
Building
Construct new electrical building to house
new electrical equipment (e.g.,
transformers, MCCs, PLCs, etc.). Also,
new electrical building may
replace/relocate electrical equipment
within existing admin building.

Size and scope of specific electrical equipment should be determined during preliminary design. Electrical equipment scope will depend on the selected treatment alternative.

Influent
Splitter Box
Construct new hydraulic structure
downstream of the existing headworks to
divert flow to the new plant and split flow
between existing plant and new plant if
necessary.

N/A
Secondary
Effluent
Pump Station
Rehab
Pump replacement and structural rehab
to secondary effluent pump station based
on findings from the condition
assessment.

Modifications to the secondary effluent pipeline or effluent weir boxes may be needed depending on plant water needs for the DWWTP, IWWTP, and future recycled water
production. It is recommended that the scope of these
modifications is refined during preliminary design.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-17 Improvement Description Considerations/Notes (1)
Plant Drain
Pump Station
Construct new plant drain pump station to
pump storm water, thickening filtrate,
decant from drying beds, and other
miscellaneous return flows back to the
influent pump station.

Size and location to be determined during preliminary design and may vary slightly depending on recommended treatment alternative.

Convert
Digesters to
Sludge
Holding
Tanks
Convert both existing digesters to sludge
holding tanks. Includes removing floating
covers, filling in conical bottom with
concrete, and installing mixing & aeration
systems.

Preliminary design requires further investigation whether to repurpose/rehab or demolish mechanical piping around
digesters. Constructing new lined aerated sludge lagoons could be considered in lieu of sludge holding tanks.

Solids
Thickening
Upgrade
Install two new thickeners with thickened
sludge pumps, polymer feed system, and
other ancillary equipment under a shade
structure.

Alternative thickening technologies (e.g., RDTs) or optimizing the existing GBT can be evaluated further during preliminary design. The City could rehabilitate the existing GBT and add a second skid for redundancy within the existing biosolids building (City should confirm functionality of existing GBT unit if this is pursued). Also, additional investigation is needed on the roof of the biosolids building to determine structural integrity.

Sludge
Drying Bed
Rehab
Replace decant gates, decant pump
station pumps, and rehabilitate drying bed
liners.

Access to drying beds and inspection was limited due to site conditions. Further investigation is required to determine extent of rehabilitation necessary. Alternative liners should be evaluated including soil-cement, asphalt, concrete, etc.

Notes:

GBT – gravity belt thickener; IWWTP – Industrial Wastewater Treatment Plant; RDT – rotary drum thickeners; PLC – programmable logic controller; MCC – motor control center. (1) Opportunities for the scope of a project element to evolve or be refined due to selected technology alternative, future decisions, or findings from further investigation.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO
CITY OF TULARE DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-18 Figure ES.9 Plant Expansion Proposed Site Layout

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-19 ES.4.3 Technology Overview
Each of the three proposed secondary treatment processes was reviewed in detail. A BioWin process model was developed for each of the alternatives to estimate the required dimensions of their secondary treatment and solids handling systems. For this planning level stage, each process was sized to achieve a maximum month effluent concentration of 30 mg/L for BOD, 30 mg/L for TSS, and 10 mg/L for total nitrogen (TN). Process flow diagrams, preliminary site layouts, O&M requirements, and technology descriptions are provided in Chapter 4 for the secondary processes:
 MLE.
 MBR.
 Oxidation Ditch.

Chapter 4 also provides a technological and operational comparison of the alternatives and should be referenced for more information.

ES.4.4 Financial Evaluation
Class 5 capital costs, 20-year O&M costs, and total life cycle costs were estimated for the three shortlisted plant expansion alternatives. Life cycle costs represent the total cash flow over the entire lifespan of a project. To evaluate these costs, a net present value (NPV) approach was used to convert both capital and O&M costs into present-day dollars.

The costs presented assume a full buildout capacity of 7.1 mgd, which is projected to meet plant capacity needs through 2043. Comparing life cycle costs is essential for selecting a recommended treatment alternative and informing preliminary capital improvement program (CIP) budgeting. If necessary, the selected alternative could also be constructed in phases to reduce initial capital expenditure.

Figure ES.10 compares the 20-year life cycle costs for the three secondary treatment alternatives, excluding common improvements. Although the MLE process has the lowest life cycle cost and the MBR alternative has the highest, all three alternatives fall within approximately 10 percent of one another, which is considered a close cost range for Class 5 estimates in accordance with AACE International guidelines and indicates no clear cost-based preference.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-20 Figure ES.10 Life Cycle Costs – Secondary Treatment Alternatives ES.4.5 Site Visits
Carollo and City staff toured three wastewater treatment plants to gain firsthand exposure to the technologies evaluated in this DWWTP Facility Plan. During each visit, City staff engaged plant operators with questions about O&M requirements, advantages and disadvantages, and seasonal operating considerations to better understand the performance of the various treatment processes.

In November the Carollo and City team visited the Visalia Water Reclamation Facility (WRF) to observe the membrane tanks, MBR cassettes, fine screens, process & scour blowers, CIP chemical system, and various pump stations; the Hanford WWTP to review the oxidation ditch, circular secondary clarifiers, RAS/WAS pump station, and sludge drying beds; and Fresno-Clovis Regional Wastewater Reclamation Facility (RWRF) to examine the bioreactors, aeration blowers, circular primary clarifiers, and rectangular secondary clarifiers.

ES.4.6 Recommended Treatment Process
The three treatment alternatives evaluated in detail are all proven technologies capable of reliably meeting regulatory effluent limits. Based on discussions with the City, there is a preference for the oxidation ditch alternative due to its minimal mechanical equipment, ease of O&M, and its ability to better manage influent variability compared to the other options. The estimated capital cost for a full greenfield buildout – including recommended common improvements – is approximately $165M. The City will work with a rate consultant to understand how the current rates can support the anticipated project costs and to identify any additional funding needs.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-21 Several opportunities exist to reduce capital costs by limiting project scope or leveraging existing infrastructure. Table ES.9 outlines potential cost-reduction options depending on further refinement of the project scope.

Table ES.9 Potential Capital Cost Reductions
Reduction Item Description Potential Project Cost Saving ($M)(1) Simpler Admin Building Reduce scope of new Admin Building (to be defined during preliminary
design).
$5.0
Rehab Biosolids Building Rehab the existing Biosolids Building instead of a new Biosolids area (further
evaluation is needed to determine if
feasible).
$2.0
Salvage Existing GBT Repurpose existing GBT for future use (further evaluation is needed to
determine if feasible).
$2.5
Sludge Lagoon Construct a new sludge lagoon at a
lower cost compared to rehabilitating
the digesters into sludge holding tanks.
$3.0
Drying Bed Rehab Define scope of sludge drying beds
depending on extent of linear repair,
mechanical replacement, etc. for cost
savings.
$1.5
TOTAL $14.0
Notes:

GBT – gravity belt thickener.
(1) Reduced project costs are high level estimates that will depend on associated scope of rehab, which has not been estimated and further confirmation that alternative is feasible.

Another way to reduce capital costs in the near term is to construct only a portion of the full buildout treatment capacity and split influent flow between the new oxidation ditch facility and the existing DWWTP. Table ES.10 outlines several potential flow-splitting approaches based on constructing selected components of the plant expansion, referred to here as Phase 1.

Table ES.10 Phase 1 Capital Cost Savings
Reduction Item Description Approximate Cost Reduction ($M) Oxidation Ditch Basins Construct one of two ox ditches. $25 Secondary Clarifiers Construct two smaller clarifiers. $7 RAS/WAS Pump Station Procure one less RAS pump and one
less WAS pump. $1
TOTAL $33
As noted previously, extensive maintenance work is needed on the existing treatment processes, but the lack of redundancy prevents units from being taken offline for repairs or cleaning. Implementing a plant expansion with split flow between the existing DWWTP and the new greenfield oxidation ditch facility would create opportunities for the City to conduct necessary maintenance, take basins offline, and improve the performance and reliability of the existing processes.

EXECUTIVE SUMMARY
JANUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN ES-22 Figure ES.11 illustrates the potential range of project costs based on different implementation approaches and cost-reduction opportunities. These cost-reduction measures – often referred to as value engineering (VE) – may lower capital costs; however, some options depend on additional investigation and/or have associated costs that cannot be quantified at this time.

Costs are shown as Total Project Costs.

Figure ES.11 Ox Ditch Project Costs Implementation Comparison CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-1
CHAPTER 1 HISTORICAL AND PROJECTED FLOWS AND

LOADS ANALYSIS

1.1 Introduction
In August 2024, Carollo completed the Master Plans for the City. Subsequently, the City initiated this Wastewater Treatment Plant Facility Planning and Water Reuse Evaluation to build upon the Master Plans, conduct an in-depth evaluation of the DWWTP, and address deficiencies for future treatment capacity, efficacy and regulatory compliance.

This chapter accomplishes the following objectives:
 Summarizes the existing DWWTP influent wastewater flows and loads based on recent (2019 to 2024) historical data provided by the City.
 Presents future influent flow and load projections based on growth assumptions from the Master Plans.
 Recommends influent design criteria to size a DWWTP expansion.

1.2 Background
The DWWTP is an activated sludge plant originally designed to treat 6.0 mgd of wastewater collected from the City’s service area. However, based on previous plant evaluations and feedback from plant O&M staff, the actual plant capacity is suspected to be less than the original rated capacity. The collection system for the DWWTP includes residential and commercial connections, and as of the last Industrial User Survey in 2012, four significant industrial users (SIUs) (food transportation companies with truck washout operations and a cardboard manufacturing facility). Tulare has eight other SIUs, primarily dairy processing facilities, that discharge to the IWWTP, adjacent to the DWWTP. The DWWTP has undergone several upgrade projects to increase capacity and improve effluent quality. Significant DWWTP improvement projects include the following:
 Water Pollution Control Facilities (1974).
 DWWTP 6 mgd Expansion Project (1996).
 DWWTP Advanced Treatment Upgrade (2004).
 DWWTP Upgrade & Expansion Project – Influent Pump Station and Headworks (2010).

Figure 1.1 shows the process flow diagram of the existing operations. Figure 1.2 shows a site layout of the existing facilities. According to City O&M staff, the biofilters are no longer in use, and the solids processes (gravity belt thickener and anaerobic digesters) have been offline since 2014.

CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-2
Figure 1.1 Tulare DWWTP Existing Process Flow Diagram
CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-3
Figure 1.2 Tulare DWWTP Existing Site Layout
The DWWTP consists of preliminary, primary, and secondary treatment. The preliminary treatment system consists of influent pumping, bar screens and grit removal. The primary treatment system includes four primary sedimentation basins, PS and primary scum pumping. The secondary treatment process consists of one anoxic basin, three aeration basins, six rectangular secondary clarifiers, RAS and WAS pumping.

Under normal conditions, primary effluent, RAS, and IMLR combine in the Biofilter Recirculation Wet Well, which is pumped into the anoxic basin. Currently, PS is pumped through the digesters, then to the domestic sludge drying beds. The digesters are not heated and are undersized, so very minimal digestion is occurring. WAS is diverted to the IWWTP for further processing and disposal. Ultimately, the City would like to send PS and thickened waste activated sludge (TWAS) to DWWTP digestion and drying beds, without having to rely on IWWTP facilities for solids handling.

1.3 Historical Flows and Loads
Carollo analyzed six years of historical data from January 2019 to December 2024 and summarized influent flows and loads for a range of conditions. Table 1.1 summarizes the definitions of these flow and load conditions and how they were calculated.

CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-4
Table 1.1 Wastewater Flow and Load Definitions
Term Definition
ADWF The average flow occurring during the three consecutive dry weather months (lowest influent flow) each year.

ADWL The average load occurring during the three consecutive dry weather months (lowest influent flow) each year.

AAF or Load The average flow or load occurring over the course of the year.

ADMMF The average daily flow occurring during the maximum flow month of the year. This is calculated as the maximum 30-day average for the year.

ADMML The average daily organic or suspended solids load occurring during the maximum load month of the year. This is calculated as the maximum 30-day average for the year. The maximum monthly load does not necessarily occur during the same period as the ADMMF.

MDF The maximum average daily flow recorded for the year.

PHF The maximum peak flow recorded for the year.

Notes:

AAF – average annual flow; ADMMF – average daily maximum month flow; ADMML – average daily maximum month load; ADWF – average dry weather flow; ADWL – average dry weather load; MDF – maximum day flow; MMF – maximum month flow; PHF – peak hourly flow.

Data outliers were removed to establish a more representative data set for the analysis. Data that was greater than the 99th percentile of the dataset for each parameter was categorized as an outlier. These outliers could be due to instrument errors, sample collection or analysis issues, short-term O&M activities, or any other factors that could misrepresent the typical conditions and performance of the plant.

Table 1.2 summarizes the historical analysis for the following constituents:
 Flow.
 TSS.
 BOD.
 Chemical Oxygen Demand (COD).

Based on the historical data, the City measures influent flow rates every day and typically collects two BOD, five TSS, and five COD concentration samples per week. Figures 1.3, 1.4, and 1.5 show the influent flows, loads, and concentrations for these constituents.

Table 1.2 Historical Influent Flows, Concentrations, and Loads Condition 2019 2020 2021 2022 2023 2024 2019-2024
Average
Average Dry Weather
Flow, mgd 4.00 3.96 4.08 4.09 3.84 3.92 3.98
TSS, mg/L 254 239 277 325 287 226 268
TSS, ppd(1) 8,930 8,050 9,720 11,020 9,180 7,340 9,040
BOD, mg/L 230 285 311 354 290 255 288
BOD, ppd(1) 8,230 9,920 10,930 12,440 10,220 8,260 10,000 COD, mg/L 658 648 733 835 757 617 708
COD, ppd(1) 22,910 21,810 25,270 28,450 24,910 19,990 23,890 CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-5
Condition 2019 2020 2021 2022 2023 2024 2019-2024
Average
Average Annual
Flow, mgd 4.17 4.12 4.21 4.26 4.16 4.03 4.16
TSS, mg/L 270 292 307 342 325 283 303
TSS, ppd(1) 9,450 10,020 10,730 12,100 11,340 9,590 10,560 BOD, mg/L 266 308 343 373 331 296 319
BOD, ppd(1) 9,190 10,630 12,070 13,280 11,460 10,060 11,120 COD, mg/L 700 728 793 869 803 730 770
COD, ppd(1) 24,450 25,000 27,690 30,730 27,800 24,750 26,740 Average Day Max Month
Flow, mgd 4.34 4.47 4.29 4.35 4.56 4.53 4.43
TSS, mg/L 294 336 394 381 418 362 364
TSS, ppd(1) 10,700 11,830 14,100 13,350 15,990 13,450 13,470 BOD, mg/L 320 356 397 419 389 379 377
BOD, ppd(1) 10,940 12,860 14,360 15,150 14,560 14,940 13,800 COD, mg/L 769 843 877 925 876 872 860
COD, ppd(1) 27,320 29,140 30,210 33,220 31,810 33,600 30,880 Max Day Flow
Flow, mgd 5.28 5.36 5.68 6.16 6.15 5.35 5.66
Peak Hourly Flow
Flow, mgd 8.19 11.13 9.91 7.77 11.80 7.69 9.42
Notes:
mg/L – milligrams per liter, ppd – pounds per day.
(1) Loads were calculated using the daily average influent flows and influent concentrations provided by the City.

CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-6
Figure 1.3 Daily Average Influent Flows
CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-7
Figure 1.4 Influent TSS, BOD, and COD Loads
CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-8
Figure 1.5 Influent TSS, BOD, and COD Concentrations
Additionally, influent ammonia (NH3-N) and TKN concentrations and their calculated influent loads were summarized for average dry weather, average annual, and average day max month conditions between January 2019 and December 2024. The City typically collects five NH3-N samples and one TKN sample per week. Table 1.3 summarizes the NH3 and TKN concentrations, and Figures 1.6 and 1.7 graph the loads and concentration data.

Over the six-year period, the influent flow meter data shows that the flows are relatively constant.

However, during the WWTP Flows & Loadings Workshop on May 15, 2025, City staff noted that most flows greater than 4 mgd, including peak daily flows, are consistently bypassed to the IWWTP upstream of the influent flow meter. City O&M staff have noted that when influent flows are greater than 4 mgd, the treatment performance suffers, and it is difficult to meet effluent objectives. The DWWTP is base loaded by running the influent pumps at a flow setpoint around 4 mgd. When peak flows cause the water level in the influent wet well to rise, water backs up into a previously abandoned sewer line that diverts flow to the IWWTP headworks. This bypassed flow is not metered. Peak flows are bypassed to the IWWTP every day. More flow is bypassed to the IWWTP during wet weather.

CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-9
Table 1.3 Historical Influent Ammonia and TKN Concentrations Condition 2019 2020 2021 2022 2023 2024 2019-2024
Average
Average Dry Weather
NH3, mg/L 34 33 37 38 39 38 36
NH3, ppd 1,130 1,120 1,250 1,290 1,340 1,220 1,220
TKN, mg/L 40 38 37 40 42 50 41
TKN, ppd 1,360 1,290 1,310 1,460 1,430 1,650 1,410
Average Annual
NH3, mg/L 35 36 38 42 41 42 39
NH3, ppd 35 36 38 42 41 42 39
TKN, mg/L 1,200 1,240 1,330 1,470 1,430 1,410 1,350
TKN, ppd 41 40 40 43 49 54 45
Average Day Max Month
NH3, mg/L 36 41 41 46 47 47 43
NH3, ppd 1,280 1,470 1,460 1,630 1,630 1,640 1,520
TKN, mg/L 44 47 45 51 62 63 52
TKN, ppd 1,600 1,610 1,530 1,740 2,190 2,210 1,810
CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-10
Figure 1.6 Influent Ammonia and TKN Loads
CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-11
Figure 1.7 Influent Ammonia and TKN Concentrations
Due to the unmetered bypass, the actual DWWTP influent flows are unknown. Between June 9 and June 23, 2025, the City operated the influent pump station in level mode, sending all flow through the DWWTP without bypassing flow to the IWWTP. The average influent flow during this period was

4.56 mgd, notably higher than the ADWF of 3.98 for the previous six calendar years.

Influent loads and concentrations for TSS, BOD, and COD have similar trends. As shown in Figures 1.4 and

1.5, influent loads and concentrations started increasing in 2020, peaked in 2022, and then decreased until the end of 2024. The ratio between peak and average flows also appears to decrease in 2023 and 2024, likely due to a change in the amount of flow bypassed to the IWWTP. Bypassing more peak flows could cause concentration data to be artificially low depending on how the composite influent sampler is programmed. It is estimated that concentration data from 2024 is not representative of true influent characteristics.

1.4 Projected Flows and Loads
Flow projections were initially developed in the sewer master plan completed in 2024, which was based on land use assumptions from the City’s most recent 2035 General Plan (adopted in October 2014). Table 1.4, shown below, summarizes the projected ADWF contributed from the existing, planned developments, and vacant infill.

CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-12
Table 1.4 Tulare DWWTP Wastewater Flow Projections
Planning Period Projected ADWF (mgd)
Existing ADWF(1) 4.5
Planned Developments(2) 1.1
Vacant Infill(3) 0.9
Total Buildout within City Limits 6.5
Notes:
(1) Based on the data collected by plant staff during the operational period in June 2025 when the plant did not bypass influent flow to the IWWTP.
(2) Assumed all wastewater flows from Planned Developments will contribute to the DWWTP projected influent. (3) Assumed that the “Industrial” land-use category summarized in the previous Wastewater Master Plan would contribute to the IWWTP influent rather than the DWWTP influent. Therefore, the projected ADWF from vacant infill constitutes the wastewater flows from the following land-use categories: single-family residential, multi-family residential, commercial, and public.

The Total Buildout projected ADWF within City Limits for the DWWTP is approximately 6.5 mgd. The projections for the other flow conditions (i.e., average annual, average daily max month, etc.) were determined using peaking factors calculated from the historical data. Peaking factors represent the various flow conditions as the ratio to the ADWF.

Table 1.5 summarizes the projected influent flows and loads to the DWWTP. Influent flows were calculated using the peaking factors. Projected influent loads were calculated using the averaged historical concentrations and the projected influent flows. It is assumed that concentrations remain constant over the planning period.

Also, during WWTP Flows & Loadings Workshop on May 15, 2025, City staff mentioned that some years in the 6-year data analysis window (January 2019 to December 2024) may not be representative of typical plant conditions. Therefore, a three-year data analysis period from January 2021 to December 2023 was deemed representative to conservatively base projected flows and loads calculations. The historical flows, their respective peaking factors, and concentrations in Table 1.5 are all averaged from the 2021 through 2023 data. Hydraulic capacities are typically sized to process max day or peak hour flows. However, treatment capacities are typically sized to handle max month loads. Therefore, max day and peak hour concentrations and loads are not presented.

Table 1.5 Tulare DWWTP Flow and Load Projections
Constituent Average Dry
Weather
Average Annual Average Daily
Max Month
Max Day Peak Hour
Flows(1)
Historical Flow, mgd 4.0 4.2 4.4 6.0 9.8
Peaking Factor, X/ADWF --- 1.05 1.10 1.50 2.50
Projected Flows, mgd(2) 6.5 6.8 7.1 9.7 15.9
CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-13
Constituent Average Dry
Weather
Average Annual Average Daily
Max Month
Max Day Peak Hour
Concentrations, mg/L(3)
TSS 296 325 397 --- ---
BOD 319 349 402 --- ---
COD 775 822 892 --- ---
NH3-N 38 40 44 --- ---
TKN 40 44 52 --- ---
Projected Loads, ppd(4)
TSS 15,900 18,300 19,200(5) --- ---
BOD 17,100 19,700 20,700(5) --- ---
COD 41,700 46,400 48,600(5) --- ---
NH3-N 2,000 2,300 2,400(5) --- ---
TKN 2,100 2,500 2,600(5) --- ---
Notes:
(1) Historical flows and their peaking factors are averaged from the 2021 through 2023 data. (2) Projected flows are calculated with the projected ADWF (6.5 mgd) multiplied by the peaking factor for each flow condition. (3) Assumed that concentrations are constant over time. The concentrations are averaged from the 2021 through 2023 historical data.
(4) Projected loads are calculated using the projected flows and concentrations shown in the rows above for each flow condition.
(5) Average Daily Max Month loads were calculated using the ADMMF and average annual concentrations.

CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-14
According to the City’s 2035 General Plan, the annual growth rate is approximately 2.7 percent. At this rate, it is estimated that the City would not exceed the projected buildout influent flows shown in Table 1.5 until 2042, which is a planning period of approximately 18 years. Figure 1.8 graphically shows this 2.7 percent annual growth for varying flow conditions until 2042.

Figure 1.8 Projected Influent DWWTP Flows
CHAPTER 1 - HISTORICAL AND PROJECTED FLOWS AND LOADS ANALYSIS FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 1-15

1.5 Design Basis for Plant Expansion

1.5.1 Regulatory Considerations
The City’s WDR and Master Recycling Permit (Order R5-2013-0019) has been active since 2013 and contains the effluent discharge limits that the DWWTP must meet for regulatory compliance. Table 1.6 shows the permitted discharge limits for BOD, TSS, and total nitrogen as described in the permit.

Table 1.6 Permitted Discharge Limits(1)
Constituent Monthly Average Daily Maximum
Domestic Discharge Specifications
BOD5, mg/L 40 80
TSS, mg/L 40 80
Commingled Discharge Specifications
BOD5, mg/L 40 80
TSS, mg/L 40 80
Total Nitrogen, mg/L 13 --
Notes:

BOD5 – five-day biochemical oxygen demand.
(1) The discharge limits are from Section C (Domestic Discharge Specifications, page 30) and Section E (Commingled Discharge Specifications, page 31) of the WDR and Master Recycling Permit (Order R5-2013-0019).

Future DWWTP expansions should be designed to meet these effluent discharge limits, including the combined total nitrogen limit.

1.5.2 Design Criteria
Future expansions of wastewater treatment plants typically design according to average day max month flow and load conditions. Table 1.7 summarizes the proposed expansion design criteria.

Table 1.7 Design Flows and Water Quality for Proposed Expansion Parameter Proposed Expansion Design Criteria(1)
Influent Flow, mgd ADMM 7
TSS, mg/L 397
TSS, ppd 19,200
BOD, mg/L 402
BOD, ppd 20,700
NH3-N, mg/L 44
NH3-N, ppd 2,400
TKN, mg/L 52
TKN, ppd 2,600
Notes:
(1) The proposed expansion design criteria is the same as the average daily max month flow and load projections shown in Table 1.5.

CHAPTER 2 – CONDITION ASSESSMENT RESULTS
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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2-1
CHAPTER 2 CONDITION ASSESSMENT RESULTS

2.1 Introduction
Carollo conducted a condition assessment in June 2025 of the critical assets at the DWWTP. The condition assessment consisted of a multi-disciplined team of engineers (mechanical, structural, and electrical) conducting visual inspection of assets to determine their general condition based on field observations (i.e., deterioration, corrosion, cracks, etc.). The condition assessment results are used to identify which assets needR&R and to prioritize projects for future budgetary planning.

This chapter accomplishes the following objectives:
 Presents and summarizes the on-site DWWTP condition assessment results.  Identifies assets in need of R&R for the near-term planning horizon.

It is important to note that the condition assessment recommendations presented in this chapter are independent of other project recommendations. For example, recommendations due to limited capacity or regulatory concerns are separate from the condition driven projects recommended in this chapter. The CIP developed as part of this project will combine all recommendations, including condition assessment recommendations, and propose a timeline for project implementation.

2.2 Methodology
A visual condition assessment was performed for critical assets at the DWWTP on June 10, 2025, by Carollo mechanical, structural and electrical engineers. Table 2.1 shows which asset types were included in the field evaluation and the typical estimated useful life (EUL).

Table 2.1 Condition Assessment Asset Types
Discipline Asset Type EUL (years)
Mechanical Pump 20
Mechanical Bar Screen 25
Mechanical Blower 20
Mechanical Diffusers 10-15
Mechanical Heat Exchanger 25
Mechanical Piping 35
Structural Basin 50
Structural Building (Metal or Masonry) 50
Structural Steel Tank 50
Structural Concrete Structure 50
Structural Wet Well 50
Electrical Switchboard / Switchgear 20
Electrical MCC 20
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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2-2
Discipline Asset Type EUL (years)
Electrical Generator 25
Electrical Transformer 30
Electrical Panel 20
Electrical Transfer Switch 25
Electrical UPS 10
Electrical VFD 10
Notes:

MCC - motor control center; UPS - uninterruptable power source; VFD - variable frequency drive.

During the condition assessment, Carollo talked with City O&M staff about asset performance, reliability, O&M requirements, and obsolescence. Each asset included in the evaluation was scored from a scale of one to five based on the asset's general condition and performance. An asset's general condition is determined by the severity of the asset's deficiencies and its function to its respective process area. Asset deficiencies include, but are not limited to, the following:
 Corrosion.
 Deterioration.
 Concrete cracking/spalling.
 Movement/settlement.
 Leaking.
 Aged coating/lining/paint.
 Limited functionality.
 Obsolescence.
 Safety risk.

Table 2.2 summarizes the scoring system that was used to assess the DWWTP critical assets. A score of 1 represents assets in good condition, and assets with scores of 4 or 5 require R&R in the near term.

Typically, an asset's condition is correlated with an asset's percent life consumed. For example, a condition score of 1 typically is associated with newer installed equipment (less than five years).

Table 2.2 Condition Scoring
Condition Score General Description Percent Life Consumed 1 (Best) Good: Asset is in good condition (no defects). 0 - 39 2 Acceptable: Asset has minor defects. 40 - 64
3 Fair: Asset has significant defects that will affect reliability or efficiency. 65 - 79 4 Poor: Asset is highly unreliable or inefficient. 80 - 89 5 (Worst) Failed: Asset is no longer able to function in its current condition. 90-100 All major structural, electrical, and mechanical assets were evaluated in the field for this DWWTP condition assessment. The next section of this chapter contains a summary of the findings. The full results and scores are included in Appendix 2A, and photos are included in Appendix 2B.

CHAPTER 2 – CONDITION ASSESSMENT RESULTS
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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2-3

2.3 Condition Assessment Evaluation
This section summarizes the mechanical, structural, and electrical condition assessment results for each process area.

2.3.1 Administration Building
The Administration Building was constructed in the 1970s. Currently, it contains offices and workspace for plant O&M staff, a laboratory, locker room, mechanical and electrical room, maintenance shop, and houses electrical equipment and an emergency generator for a portion of the plant's connected electrical loads.

Structural: The Administration Building is a single-story structure with a wood framed roof supported by reinforced concrete masonry walls. The foundation system consists of a reinforced concrete slab on grade and shallow concrete wall footings. Ground supported electrical equipment is supported on concrete housekeeping pads.

The main structure, which includes the wood framed roof, concrete masonry unit (CMU) walls, electrical pads and the slab on grade, is in good condition. The existing roof membrane appears to be damaged, and evidence of water stains was observed in the ceiling tiles. At several window frames, there was evidence of water intrusion, which also appeared to damage the floor covering adjacent to it. Also, there was damage to the exterior wood framed canopy, likely due to water intrusion. Overall, the Administration Building is in moderate condition. Moderate structural renewal or rehabilitation will be required.

Electrical: Several major pieces of electrical equipment are located in the Administration Building. They are described in more detail in the electrical system section below.

The City has outgrown their admin building and would like a new building to support the functions of the wastewater plant. The City would like a larger laboratory and more space to house additional O&M staff.

It is recommended that the admin building is included as part of the plant upgrade.

2.3.2 Influent Pump Station and Headworks
Both the Influent Pump Station and Headworks began operating in 2012. Influent sewage from the domestic collection system flows by gravity to the Influent Pump Station wet well. The Influent Pump Station includes four vertical turbine influent pumps, where raw wastewater is pumped to the Headworks.

The Headworks consists of influent screening, compactor, grit removal, grit classifier, bypass piping, and ancillary equipment.

Mechanical: Overall, the mechanical equipment is in good condition. The influent pumps, bar screens, compactors, classifier, and grit pumps have normal wear and aging. No major deficiencies were observed.

The grit washer was replaced within the last two years. The City is planning on rehabilitating the grit cyclone in the near future.

Process: The plant can run the Influent Pump Station in level mode or in flow mode. During flow mode, the pumps run at a constant speed to pass a fixed flow through the plant. In level mode, the pump speed ramps up and down to try to maintain a fixed level in the wet well. The plant typically runs the pumps in flow mode to send roughly 4 mgd through the plant. Above 4 mgd, the plant struggles to maintain performance. When influent flows are greater than 4 mgd, level in the wet well rises and surcharges the CHAPTER 2 – CONDITION ASSESSMENT RESULTS
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influent sewer line. Above a certain level, flow bypasses into a previously abandoned industrial line, where flow goes to the IWWTP. Once the plant has additional capacity, the influent pumps can run in level mode and pass all flow through the DWWTP. Then, the City may want to sever the hydraulic connection between the domestic collection system and industrial WWTP.

Structural: The Influent Pump Station and Headworks are constructed with reinforced concrete slabs, walls, and foundations. The grating, guardrails and stairs are constructed of steel framing. Through visual observation, the grit tank and grit influent channel appear to be in excellent condition with no defects observed.

Electrical: The Influent Pump Station and Headworks have newer stainless steel junction boxes, hand-offauto (HOA) operators, and vendor control panels (VCPs) that are in good condition with many years of remaining useful life.

2.3.3 Primary Sedimentation Basins
The DWWTP has four chain and flight primary sedimentation tanks to remove scum and heavier solids.

Two primary sedimentation basins were installed in 1974, and two more basins were installed in 1996.

Screened influent is piped by gravity from the Headworks through the primary influent flow meter and then flows into the primary influent channel. The primary influent channel is aerated to prevent solids from settling.

Mechanical: The scour air piping in the primary influent channel is significantly corroded and the piping has failed. It is recommended to replace the submerged channel air piping with stainless steel pipe in the near future. The primary clarifier drive mechanisms are corroded and worn. It is recommended to rebuild or replace the drives to improve performance and reduce wear. Additionally, the primary clarifiers have an uneven flow split over the effluent weirs. The v-notch weirs have slotted anchor holes and can be adjusted a couple inches. It is recommended to laser level and adjust the weirs to achieve an even flow split between clarifiers.

Structural: The sedimentation basins are constructed with reinforced concrete slabs, walls, and mat foundation. Metal guardrails are mounted to the concrete slab on the walkways. There appear to be metal conduits attached to the concrete basin walls. A protective coating is applied on all wetted parts of the basins.

In general, the basin structures appear to be in good condition with minor defects. The following defects were observed in the field: Pipes and pipe fittings in the basins are corroded, minor cracking and spalling at concrete surfaces (reinforcements are not exposed), and basin coating at the water surface showing delamination. However, the condition of the concrete surface below the waterline could not be observed and remains unknown. It is assumed to be in worse condition than the area above the waterline.

Therefore, it is recommended to resurface the concrete with a polyurethane coating within the next five years, when the basin can be drained, as the coating application requires a completely dry surface.

Although current structural condition does not impact the structure's function, Engineers recommend to verify the condition of the basin below waterline.

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2-5

2.3.4 Biofilter Recirculation Wet Well
The Biofilter Recirculation Wet Well was constructed in 1974. Primary effluent is piped by gravity into the biofilter recirculation wet well. The biofilter process has been abandoned for about the last ten years, but the recirculation wet well is still used to pump primary effluent, RAS, and MLR to the anoxic basin.

Structural: Overall, the Biofilter Recirculation Wet Well is in good condition, and it is fully functional.

There is minor spalling and cracking at the guardrails. No structural rehabilitation is required assuming normal maintenance is performed. However, it is recommended to verify the condition below the waterline. If immediate rehabilitation is not necessary, it should be repaired with the primary basin in the next five years.

2.3.5 Anoxic Basin
The DWWTP has a single, two-pass, anoxic basin with fiberglass reinforced plastic (FRP) baffle walls separating different zones. The anoxic basin was built in 2004 and was constructed with several swing zones that can operate as either aerated or unaerated. The anoxic basin and aeration basin together comprise the bioreactor, which provides biological treatment.

Mechanical: Above-ground piping appears to be in moderate condition. The mixers and diffusers were submerged during the assessment and could not be visually inspected onsite. Fine bubble diffusers have an estimated life of 10 to 15 years. Biological fouling on diffusers is common and reduces the oxygen transfer efficiency. When possible, basins should be drained every two to three years and diffusers cleaned with a mild acid or scrubbed mechanically to remove scum. O&M staff did not indicate any issues with the mixers.

Structural: The structure consists of reinforced concrete slabs and interior basin walls with protective coating. Reinforced concrete retaining walls were installed at two sides of the basin. Overall, the structure is in good condition, with only minor cracking observed in the slabs and retaining wall. The structure is well maintained and does not require rehabilitation currently.

2.3.6 Aeration Basins
The DWWTP has three aeration basins. Aeration Basins Number (No.) 1 and No. 2 were installed in 1996, and Aeration Basin No. 3 was installed in 2004. The anoxic basin effluent feeds into a channel that splits flow to three single-pass aeration basins.

Mechanical: The aeration piping in the aeration basins appears to be in adequate condition. The spray water piping is corroded and should be replaced as needed as it fails. The aeration basins are older than the anoxic basin and diffusers have not been replaced since they have come online. When additional capacity comes online, it is recommended to inspect the diffusers and clean or replace as needed.

Structural: The aeration basins are constructed with reinforced concrete slabs, walls, and mat foundation.

Metal guardrails are mounted to the concrete slab on the walkways. A protective coating is applied to the basin walls up to the water fill line. Through visual observation, the structures were generally in good condition. They are well maintained with minor wear. There are minor cracks on the concrete surface but will not affect the structure's functionality. Structural rehabilitation is not required. Although immediate rehabilitation is not required, it is recommended to verify the condition below the water line within the next five years with the other basins.

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2-6

2.3.7 Blower Building
The blower building was constructed in 1996 and is an unconditioned, steel frame metal structure with corrugated metal siding and roof deck. The building houses four centrifugal blowers that provide process air to the swing zones of the anoxic basin, aeration basins, and secondary process channel air.

Mechanical: Overall, the four aeration blowers are in poor or failed condition. The blowers and associated equipment are aged, and City staff indicated that they are not able to meet air flow rates during high aeration demand periods. This could also be due to biological fouling on the diffusers not able to transfer sufficient oxygen. New aeration blowers are recommended in the near term.

Structural: The blower building appears to be in sufficient structural condition, and no structural defects were observed.

Electrical: The blowers have a VCP that is outdated and should be replaced when the blowers are replaced. The blower motors and associated conduits should also be replaced with the blowers. The blowers are currently fed from the control room in the admin building. If a new blower building is constructed, the new blowers can be fed from electrical room (ER) 6 or from a new electrical building.

2.3.8 Secondary Sedimentation Basins
The DWWTP has a total of six secondary sedimentation basins. Secondary Sedimentation Basins No. 1 through No. 4 were installed in 1974, and two additional basins (No. 5 and No. 6) were installed in 1996.

Aeration basin effluent (mixed liquor) collects in a channel that feeds the six secondary sedimentation basins. The secondary sedimentation basins are chain and flight, similarly to the primary sedimentation basins, and they remove solids and scum.

Mechanical: The mixed liquor channel air piping appears to be in adequate condition but could not be observed because the piping was submerged. Mixed liquor is corrosive and the channel has been in service for several decades. It is likely that the piping is corroded and in poor condition. It is recommended to conduct a more detailed observation and replace the channel air piping with stainless steel pipe as necessary. The secondary clarifier drives appear to be in decent condition. There is an uneven flow split between the secondary clarifiers. Adjusting the effluent weirs, similar to the recommendation for the primary clarifier, may help improve the flow split. However, the flow split may also be caused by the configuration of the mixed liquor channel feeding the clarifiers, or the fact that clarifiers 1-4 are shallower than 5 and 6. Baffle plates in the mixed liquor channel or adding downward opening weir gates to the clarifier inlet could help improve the flow split to the clarifiers.

Structural: The secondary sedimentation basins are constructed with reinforced concrete slabs, walls, and mat foundation. Metal guardrails are mounted to the concrete slab on the walkways. A protective coating is applied to the basin walls up to the water fill line. Through visual observation, the structure was overall in good condition with minor defects. The observed defects are as follows: delaminated concrete wall coating, minor cracking at concrete wall and slab floor, and concrete spalling at gratings. These defects will not impact the structure's intended function, and significant rehabilitation is not required. It is recommended to verify the condition of the concrete surface below the water line, and apply protective coating system within five years. Also, if exposed reinforcement is observed by severe concrete deterioration during future assessment, partial depth repair shall be performed.

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2-7

2.3.9 Pump Gallery
The pump gallery is a concrete vault below grade that houses the primary sludge pumps, primary scum pumps, biofilter feed pumps, RAS pumps, WAS pumps, secondary scum pumps, and the primary channel air blower.

Mechanical: The primary sludge pumps, scum pumps, RAS pumps, and WAS pumps are all in good condition. These pumps were replaced within the last five years and show normal aging. Two of the biofilter feed pumps have been rehabilitated within the last five years with motor and valve replacement.

The primary channel air blower is in excellent condition. No rehabilitation or replacement of existing mechanical equipment is required.

Structural: The pump gallery pit consists of reinforced concrete retaining walls with a concrete slab on grade. Around the walls of the pit, metal guardrails and access walkways are installed. Mechanical equipment is supported by concrete housekeeping pads over the slab on grade. The concrete slab and walls were generally in good condition throughout the retaining walls. The pump gallery is fully functional without defects that have impact on its intended function.

Electrical: Local controls and conduits for the pumps in the gallery appear to be in adequate condition and don't need to be addressed.

2.3.10 Secondary Effluent Pump Station
The secondary effluent pump station conveys effluent from the secondary sedimentation basins to the outlet structure, where it is combined with the industrial plant effluent before going to the percolation ponds and agricultural fields.

Mechanical: The secondary effluent pumps are in poor condition. Two of the pumps are used to supply plant water to the odor control scrubbers at the IWWTP. All four secondary effluent pumps are aged and have corrosion. Secondary Effluent Pump No. 1 is not operational and no longer has a motor. Pumps No. 3 and No. 4 leak water onto the metal base and concrete slab. Replacement of the secondary effluent pumps are recommended in the near term.

Hydraulics: The secondary effluent pump station discharges into an existing effluent box. A weir within the effluent box provides head on the suction side of the GBT washwater booster pump station.

Secondary effluent then flows south by gravity through approximately 2,300 feet of pipe from the effluent box to a mixing box where it combines with industrial effluent. The 24-inch effluent pipe increases to a 30-inch about 825 feet upstream of the mixing box. There is also a flow control box with an overflow weir located between the effluent box and the mixing box. The origin and purpose of the flow control box is unknown. Carollo's Hydraulix® tool was used to model the predicted hydraulic grade line throughout the secondary effluent system. The model demonstrates that the effluent box has the capacity to pass the rated flow of the secondary effluent pump station, which is approximately 8.4 mgd. However, plant staff have observed the effluent box overflowing when the secondary effluent pumps are running at peak flows. It is possible that the overflow could be caused by sediment buildup or debris stuck at inlets/outlets of the box structures. It is recommended to inspect the box outlets and pipeline with a camera.

Additionally, modifications to the secondary effluent pump station and boxes and/or pipelines is needed to be able to pass the future design peak hour flow.

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Structural: The secondary effluent pump station is constructed with a reinforced concrete slab topped with metal grating. The structure is generally in good condition; however, the pump base plates exhibit rust and may require minor repairs. The replacement for base steel plate and support is recommended.

2.3.11 Biosolids Building
The biosolids building was constructed in 1996 and is an unconditioned, steel frame metal structure with corrugated metal siding and roof deck. The building houses a gravity belt thickener and two combination heat exchangers and boilers for sludge heating.

Mechanical: The GBT has been offline since 2014, however, it appears to be in acceptable condition. The polymer pump and thickener pumps are also in acceptable condition. Plant staff indicate that they start up and run the equipment periodically to confirm that the equipment remains operational. However, 30 years is near the expected useful life of a thickener unit. It is recommended that the plant staff start up the GBT and operate it for an extended period of time, several weeks to months, to confirm they are comfortable keeping it in service rather than replacing it with a new thickening system.

There are two combination boiler / heat exchangers in the Biosolids Building that can run on natural gas or unconditioned digester gas to provide sludge heating. One unit has been gutted of its components and is not operational. City staff noted that the other heat exchanger may be operational but has been offline for many years. The sludge heating units are likely near the end of their useful life. Additionally, rehabilitating the units to place them back in service will likely require coordination with the Air District, which may require additional emissions control devices that could be difficult to install on the existing units. If sludge heating is required in the future, it is recommended to demolish the existing units and replace with new units.

Structural: The biosolids building was built in 1996. It is constructed of a metal roof deck and exterior metal cladding around the exterior perimeter. The metal roof deck is supported by metal joists spanning to steel wide flange beams. The roof beams are supported by steel wide flange columns. The foundation system consists of reinforced concrete slab on grade and isolated spread footings. The exterior cladding is supported by horizontal steel girts which are attached to the vertical columns. Mechanical equipment is supported by concrete housekeeping pads placed over the slab on grade. The structure is generally in good condition. The following defects were observed in the field: Rust damage was observed at the metal roof deck. The existing roofing membrane may also be damaged, however access to roof was not available to confirm this. It is recommended to remove and replace damaged section of the metal deck.

The second option is to field verify the thickness of deck remaining, confirming the reduced metal thickness has not compromised the structural integrity. Field verification for roof membrane is recommended with a roofing specialist.

Electrical: The GBT has a VCP that is outdated. If the GBT is to be salvaged, it is recommended to replace the VCP with a more modern one.

2.3.12 Anaerobic Digesters
The DWWTP has two concrete, floating cover anaerobic digesters with recirculation pumps that were constructed around 1974.

Mechanical: The pump and piping equipment for Digester No. 1 appears to be in acceptable condition.

There is a minor leak from the Digester No. 1 pump onto the base. Repair of the leakage and recoating is CHAPTER 2 – CONDITION ASSESSMENT RESULTS
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recommended in the near term for Digester No. 1 mechanical equipment. City staff mentioned that Digester No. 2 is not operational due to piping issues. Video inspection of the sludge recirculation, feed, and transfer piping is recommended to identify the specific sections of pipe that need to be replaced before putting the digester back into service. Alternatively, the piping could be abandoned in place and new piping located as needed depending on the intended functionality of the digester once it is placed back into service.

Structural: The digesters were built in the year 1974 and 1996. The structures are constructed with reinforced concrete walls and a steel framed lid. There is a metal staircase providing access to the roof adjacent to the tanks. The digesters appeared to be in decent condition. The following defects were observed in the field: There were minor cracks in the concrete walls, and in some areas, there was evidence of fluid leakage on the exterior wall surface cracks. There were also areas where the exterior wall coatings appeared to be worn or damaged. The existing cracks can be sealed by polymer grout or epoxy injection. The damaged coating can be repaired by remove and replace coating with protective coating system within the next five years. Overall, the structures are in decent condition and are fully functional with only minor defects. It is recommended to recoat the walls every five to ten years with protective coating system.

Electrical: Some conduits around the digester show severe corrosion and deterioration and need to be replaced. Areas around the digester are classified as hazardous per National Fire Protection Association (NFPA) 820. It is recommended to complete an NFPA 820 evaluation before any electrical or mechanical upgrades are made.

2.3.13 Sludge Drying Beds
The sludge drying beds were constructed in 1996 and the bottom and side slopes were rehabilitated with a soil cement liner in 2004. From the digester, sludge is sent to 14 domestic sludge drying beds. Each drying bed can be decanted and supernatant pumped back to the influent pump station. Periodically, dried sludge is hauled offsite by a third-party for disposal.

Mechanical: Each sludge drying bed has a decant box with a downward opening weir gate. The decant is routed to a common decant pump station, with a single submersible pump that sends supernatant back to the head of the plant. The condition of the decant boxes and pump station could not be observed during the site visit. A follow up inspection is recommended to evaluate the condition of the mechanical assets and determine if mechanical improvements are required.

Structural: The domestic sludge drying beds are soil cement lined but the condition could not be determined during the site visit. It is recommended that the condition of the soil cement lining be confirmed. If rehabilitation is required, an underdrain system may be necessary in order to receive regulatory approval from the Regional Board. Concrete or asphalt lining the sludge drying beds is recommended in the long-term.

Electrical: The supernatant box at the drying beds has a control panel with disconnect switches that appeared to be in poor condition and it is recommended to be replaced.

2.3.14 Electrical System
Southern California Edison (SCE) supplies power to the DWWTP via 12 kilovolt (kV) lines. The 12kV power loops through the medium voltage power system, providing primary selective redundant feeds to CHAPTER 2 – CONDITION ASSESSMENT RESULTS
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transformers. The SCE meter at the service entrance captures power consumption data for whole plant.

Transformers rated for 3750 kilovolt-ampere (kVA) and 1500 kVA step down 12kV to 480/277 volt (V), 3 phase power and distribute this via underground conduits/cables in duct banks and cable trays to MCCs, VFDs, switchgears (SWGR), and switchboards (SWBD). The feeders have protective relays that monitor the system in real time and perform protective functions.

Electrical equipment for the DWWTP is located in the control room in the Admin Building and in ER 6. The control room houses SWGR-PG and a 615 kilowatt (kW) standby generator, which feeds several MCCs, which power most of the equipment for the plant. ER 6 houses SWBD-1 and a 2000 kW standby generator, which feeds MCC-2, which powers the influent pump station and headworks equipment.

SWBD-1 was also sized for future MCCs to replace the existing MCCs in the control room.

A plant expansion would include additional tanks and equipment west of the existing plant. Although there is spare capacity in SWBD-1 in ER 6, the distance from ER 6 to new infrastructure would result in large voltage drop through the conductors at low voltage. It is recommended that a plant expansion include a new electrical building with a new 12 kV feed. A new precast concrete vault with a new pad mounted switch provided by SCE would intercept the existing 12 kV loop around the plant and feed a new electrical building and transformer to provide 480 V power to a new switchgear and MCCs to power new equipment. Connected loads that are fed from the control room in the admin building should be rewired to be fed from a new electrical building or from ER 6 so that the electrical equipment in the control room can be abandoned or demolished. The electrical equipment in ER 6 would continue powering existing equipment in the field. It is recommended to begin coordination with SCE as soon as preliminary electrical loads for the plant expansion are identified because applying for and getting approval through SCE for a new feed may take over a year.

Structural: ER 6 was built in 2012. The structure was in excellent condition and no defects were observed.

Rehabilitation is not required.

Electrical: The following bullet points summarize the assessment and recommendations of the overall electrical system.
 Electrical equipment in the administrative building is next to occupied spaces, including the laboratory. For new construction, it is recommended to relocate major electrical equipment from occupied buildings and build dedicated electrical buildings for fire and life safety purposes. » Items stored in the control room of the admin building may be introducing a National Electrical Code (NEC) violation. It is recommended to keep all unnecessary items away from these rooms and to maintain safe clearances in front of the electrical equipment.  A short circuit study is recommended for the entire facility. The short circuit study maps out the power sources and connected loads and is used as the basis for several follow up studies that are needed for the facility.
» Arc flash labels seen on most electrical cabinets were out of date and should be updated every couple years or whenever there is a change to the electrical system. It is recommended to add arc flash labels on each bucket on all MCC sections, switchboards, switchgears and other equipment in the electrical rooms.
» Protective device coordination study of the facility using modern software is needed to properly select and set relay settings for overcurrent and ground fault. Review protection schemes for existing transformers, generators, feeders, VFDs, motors, cables, MCCs, switchboards, and CHAPTER 2 – CONDITION ASSESSMENT RESULTS
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switchgears and suggest improvements to increase reliability. The DWWTP has electromechanical relays in several locations, which are more outdated for a WWTP application and less reliable than electronic multifunctional relays. It is recommended to replace all electromechanical relays with electronic multifunctional relays.
» Equipment rating and evaluation study is recommended to confirm that the equipment can meet its short circuit rating. Software tools such as ETAP will be used for this purpose. » A load flow analysis could be done to help confirm the connected loads and suitable capacity for emergency generator power.
 Several of the underground conduits and cables are over 40 years old. It is recommended to visually inspect underground duct banks and cable runs with endoscopic cameras or other means to determine if the condition of underground electrical equipment has degraded and requires replacement. Additionally, an underground cable ampacity study can be done to confirm rating of existing electrical equipment. Consider replacing conduits and cables over 40 years older.  The NFPA 820 defines hazard classification areas for process areas throughout wastewater treatment plants and is updated every five years. It is recommended to review compliance with NFPA 820 to ensure that all improvements and equipment replacements are made in compliance with the most recent NFPA 820 requirements and as needed to address safety concerns.  Given the age of much of the electrical equipment, a grounding study of the whole DWWTP is recommended. Review the location of ground rods and copper grid and ground resistance. Perform ground resistance checks on existing HOA operators in the plant. Check presence of equipment grounds on all electrical equipment.
 It is recommended to connect existing electrical equipment to the supervisory control and data acquisition (SCADA) system for improved performance and safety. The City is conducting a SCADA Master Plan in the near future that will recommend SCADA improvements as part of a facility upgrade.

In summary, the equipment in ER 6 is newer and has sufficient remaining useful life and does not need immediate attention. Equipment in the control room is much older and should be demolished or abandoned as part of the future plant expansion. Connected loads fed from the control room should be relocated to a new electrical building or to ER 6.

2.4 Recommendations
Table 2.3 lists the recommendations identified from the condition assessment results. These improvements are recommended to be included as part of the plant expansion project.

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Table 2.3 Summary of Recommended Improvements
Process Area Recommendation
Administration Building Replace with new building.

Influent Pump Station Put check valves on drain lines going into the wet well.

Primary Sedimentation Basin Recoat basins, replace channel air piping, level weirs, rebuild/replace drive mechanisms.

Anoxic Basin Clean/replace swing zone diffusers.

Aeration Basin Clean/replace diffusers.

Blower Building Replace blowers.

Secondary Sedimentation Basin Recoat basins, level weirs, modify flow split.

Secondary Effluent Pump Station Replace pumps, motors, base plates, and mechanical components, inspect box outlet for blockages, increase capacity to combined effluent box.

Biosolids building Inspect roof, decommission sludge heating units, replace GBT VCP, run GBT to confirm functionality.

Anaerobic Digesters Apply injection grout, recoat tanks, inspect/rehab process piping.

Sludge Drying Beds Asphalt or concrete line beds, rehab/replace decant gates and pumps.

Electrical System Relocate loads from Control Room, conduct short circuit study, update arc flash labels, replace older conduits/ cables, conduct grounding study.

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CHAPTER 3 EXISTING PLANT EVALUATION

3.1 Introduction
Carollo developed a wastewater process model of the City’s Domestic Wastewater Treatment Plant (DWWTP) using EnviroSim’s BioWin wastewater treatment simulation software (version 6.3). Process modeling supports desktop evaluation of existing processes, assessment of optimization and enhancement alternatives, and the design of new facilities prior to implementation. The BioWin wastewater treatment simulator is a common tool used in the wastewater industry for planning and evaluation.

This chapter accomplishes the following objectives:
 Presents and summarizes the two-week special sampling campaign data.  Describes the steps taken to develop and calibrate the process model.  Assesses existing DWWTP plant capacity.

3.2 Special Sampling Campaign
A two-week special sampling campaign for the DWWTP was conducted between January 21, 2025 and February 3, 2025. A special sampling campaign was conducted for the BioWin calibration to obtain detailed, plant-specific data for accurate wastewater characterization, which goes beyond the standard operational data regularly sampled from the DWWTP. Special sampling campaigns provide the following:
 Detailed Wastewater Fractionation:
» To accurately simulate biological and chemical processes, BioWin models separate the influent organics and nitrogen in the wastewater into different fractions (i.e., readily biodegradable chemical oxygen demand (COD), slowly biodegradable particulate COD, unbiodegradable particulate COD). This data is typically not measured in daily operations.  Plant-Specific Parameters:
» Default kinetic and stoichiometric parameters in the BioWin model may not accurately represent the unique characteristics of a treatment plant’s influent composition, microbial population, or operational conditions. Special sampling allows for the determination of those specific values, which provide a more robust and reliable process model performance.  Performance Verification:
» The data collected from different locations within the wastewater treatment plant (i.e., influent, effluent, mixed liquor suspended solids, etc.) allows engineers to compare the model’s predictions with actual observed performance, enabling the fine-tuning of model parameters until good agreement with historical data is reached.

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A two-week sampling period provides sufficient time for regular daily patterns to be observed and for data to be averaged into a representative profile. The special sampling campaign fills the gap between typical operational data and plant-specific detailed information used for the BioWin model characterization, ultimately leading to a more reliable and predictive model for process optimization, troubleshooting, and plant expansion planning.

Appendix 3A shows the two-week wastewater characterization sampling plan, which provides a list of sampling constituents, analytical methods, type and number of samples, and sample locations. The City’s plant staff conducted the sampling program. Samples were analyzed in the City’s plant laboratory and with support of a third-party laboratory. Table 3.1 summarizes the results from the special sampling program performed by the City.

Table 3.1 Two-Week Wastewater Characterization Sampling Program Data Summary Sampling
Parameter Units Influent (1) Primary Effluent (1) Aeration Basin Influent(1) Secondary
Effluent(1) Primary Sludge(2)
BOD mg/L 287 --- --- 33 ---
sBOD mg/L 165 --- 12 4 ---
TSS mg/L 271 96 4,385 98 31,509
VSS mg/L 252 87 3,842 83 28,455
COD mg/L 718 --- --- 121 ---
sCOD mg/L 307 --- 51 44 ---
NH3 mg/L 40 --- 31 26 ---
TKN mg/L 49 --- --- 39 ---
sTKN mg/L 36 --- --- 24 ---
Nitrite mg/L ND --- --- ND ---
Total Oxidized
Nitrogen
mgN/L 0.7 0.21 0.14 ---
Alkalinity mg/L 225 --- 229 206 ---
VFA mg/L 101 --- 143 --- ---
Phosphorus mg/L 12 --- --- 6.5 ---
Orthophosphate mgPO4/L 7 --- ---
pH S.U. 7.2 7.4 7.2 7.4 ---
Temperature Celsius 14 10 15 15 ---
Notes:

BOD – 5-day biochemical oxygen demand; sBOD – soluble biochemical oxygen demand; TSS – total suspended solids; VSS – volatile suspended solids; COD – chemical oxygen demand; sCOD – soluble chemical oxygen demand; NH3 – ammonia; ND – non detect; TKN – total Kjeldahl nitrogen; VFA – volatile fatty acid; mgd – million gallons per day; mg/L – milligrams per liter; S.U. – standard units.
(1) All data reflects average of two-week sample period (January 21, 2025 – February 3, 2025). Data collected from 24-hour composite samples.
(2) Four primary sludge grab samples were collected daily. The reported value is the average of all grab samples from January 21, 2025 – February 3, 2025.

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The influent wastewater characterization data shown in Table 3.1 was used to adjust the default BioWin characterization fractions. The primary effluent, aeration basin influent, secondary effluent, and primary sludge data were used in combination with historical plant data to calibrate the model, as described in the following section.

One key observation is that the special sampling occurred when the plant was neither nitrifying nor consistently meeting several of the effluent waste discharge requirement (WDR) limits. Consequently, some of the wastewater characteristics throughout the plant, particularly in the secondary effluent, may not represent the plant’s typical or designed wastewater characteristics.

3.3 Model Development and Calibration
The development and calibration of a BioWin model involves configuring the model with the plant’s existing processes and then calibrating it against historical plant data by adjusting model parameters. This process includes identifying key parameters and using data to match simulated outputs (e.g., effluent concentrations) with measured data.

BioWin uses a COD based model to simulate performance. Based on various input parameters, the model calculates the different COD components, including readily biodegradable, acetate, non-colloidal slowly biodegradable, unbiodegradable soluble, and unbiodegradable particulate. TKN, inert suspended solids (ISS), and total phosphorus are additional input parameters. BOD and TSS are calculated based on the input parameters.

3.3.1 Model Configuration
As shown in Figure 3.1, the BioWin model was configured using the existing DWWTP processes (Chapter 1 provides a description of the existing DWWTP processes). Physical dimensions (e.g., volume, area, depth) of each unit process and flow rates (e.g., WAS, RAS, influent) are inputs to the model. All dimensions, assumptions, and other applicable process inputs were based on the 1996 DWWTP Plant Expansion Project and 2004 Advanced Treatment Upgrade design criteria. Based on discussion with plant staff, all basins (primary, secondary, aeration, anoxic) remain in service year-round without redundancy. Also, while zones 3 through 6 of the anoxic basin were designed as swing zones, zone 6 is the only zone that is currently aerated.

Abbreviations: BSN – basin; ZN – zone; MLR – mixed liquor return.

Figure 3.1 DWWTP BioWin Model Configuration
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3.3.2 Influent Characterization
Results from the two-week wastewater characterization sampling program, as previously discussed in Section 3.2, were used to determine the plant’s influent wastewater fractions. Table 3.2 compares the wastewater characteristic fractions that were modified for the process model. All other model parameter values were set to default.

Table 3.2 Model Influent Wastewater Fractions
Wastewater Fraction BioWin Default Value from Model
Fvfa(1) 0.150 0.750
Fxsp(2) 0.750 0.770
Fus(3) 0.050 0.160
Fup(4) 0.130 0.170
Fna(5) 0.660 0.820
FupN(6) 0.070 0.065
Notes:
(1) Fraction of volatile fatty acids (VFA).
(2) Fraction of non-colloidal slowly biodegradable chemical oxygen demand (COD). (3) Fraction of unbiodegradable soluble COD.
(4) Fraction of unbiodegradable particulate COD.
(5) Fraction of ammonia to TKN.
(6) Fraction of nitrogen:COD ratio for unbiodegradable particulate COD.

The volatile fatty acid wastewater fraction has the largest adjustment compared to its BioWin default fraction. This fraction was increased to reflect the higher volatile fatty acid content in the DWWTP influent based on the two-week special sampling campaign data (see Table 3.1).

The higher fraction of VFAs, unbiodegradable soluble COD, and ammonia, could indicate a larger portion of higher strength commercial or industrial discharges, such as a restaurant or food processor. It could also be due to longer residence times in the collection system that is causing wastewater to ferment and hydrolyze, changing the wastewater characteristic compared to what is typically expected. Fermentation and hydrolyzation is also consistent with the higher than typical ammonia to TKN ratio (Fna) observed in the City’s influent.

3.3.3 Model Calibration
BioWin wastewater treatment models are typically calibrated using a three-month dataset derived from stable wastewater operating conditions. Historical plant data from six years of data (January 2019 – December 2024) was evaluated for a stable three-month calibration period. Based on previous discussions with the City and supported by the historical plant data, the DWWTP has had challenges operating consistently, including difficulty meeting effluent WDR limits. Existing plant deficiencies are discussed in a subsequent section. The three-month calibration period chosen to calibrate the DWWTP BioWin model was July 1, 2023 to September 30, 2023, which had relatively stable operating conditions (e.g., MLSS, RAS, WAS, SRT, etc.) compared to other data periods and met its WDR effluent limits. The calibration period reflects average dry weather (ADW) conditions.

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The model was calibrated to reflect the average operating conditions during the calibration period (e.g., number of process units in service, primary sludge flow, dissolved oxygen [DO], secondary sedimentation basin performance, RAS flow, WAS flow, etc.). Using average values from the model calibration period as inputs, a steady-state simulation was run. Table 3.3 compares the results of the calibrated model with average plant data from July 1, 2023 to September 30, 2023.

Table 3.3 Model Calibration Results
Parameter Units Calibration Period Data Value BioWin Model Results Difference Influent
Flow mgd 4.06 4.06 0%
BOD concentration mg/L 325 312 -4%
TSS concentration mg/L 300 305 +2%
NH3 concentration mg/L 41 42 +2%
TKN mg/L 51 51 0%
Alkalinity mg/L 242 242 0%
pH S.U. 7.2 7.2 0%
Temperature Celsius 25 25 0%
Primary Process
PE flow mgd 4.02 4.02 0%
PE BOD concentration1 mg/L ---- 217 ----
PE TSS concentration mg/L 96 139 45%
PE COD concentration mg/L 469 528 13%
% TSS removal1 % ---- 55 ----
Secondary Process
Secondary Influent Flow mgd 15.02 15.09 0%
Anoxic Basin DO mg/L 0.24 0.24 0%
Aeration Basin DO mg/L 1.12 1.12 0%
Airflow scfm 2,672 2,876 8%
MLSS mg/L 2,819 2,821 0%
MLVSS mg/L 2,331 2,232 -4%
SVI mL/g 137 --- ---
Aerobic SRT days 4.0 4.3
Total SRT2 days 6.0 6.6 -4%
RAS flow1,3 mgd ---- 3.04 ---
RAS concentration mg/L 6,350 6,432 1%
MLR flow1,4 mgd --- 8.12 ---
Secondary Effluent
BOD concentration mg/L 13 9 -4 mg/L
TSS concentration mg/L 19 20 +1 mg/L
NH3 concentration mg/L 6 5 -1 mg/L
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Parameter Units Calibration Period Data Value BioWin Model Results Difference Nitrate concentration mg/L 3 5 +2 mg/L
Total Nitrogen concentration mg/L 10 14 +4 mg/L
TKN concentration mg/L 7 8 +1 mg/L
Alkalinity as CaCO3 mg/L 132 115 -13%
Temperature Celsius 25 25 0%
Solids
PS flow gpd 41,800 41,800 0%
PS load1, 5 ppd 6,940 5,681 18%
WAS flow6 gpd 95,200 100,000 5%
WAS load ppd 5,051 5,100 1%
Notes:

BOD – biochemical oxygen demand; TSS – total suspended solids; NH3 – ammonia; TKN – total Kjeldahl nitrogen; VFA – volatile fatty acid; gpd – gallons per day; mg/L – milligrams per liter; S.U. – standard units; PE – primary effluent; MLSS – mixed liquor suspended solids; MLVSS – mixed liquor volatile suspended solids; SVI – sludge volume index; SRT – solids retention time; RAS – return activated sludge; MLR – mixed liquor return; PS – primary sludge; WAS – waste activated sludge; CaCO3 – calcium carbonate.
(1) Not directly measured at the DWWTP.
(2) Total SRT was calculated using the total anoxic basin and aeration basin volumes, 7-day running average MLSS concentrations, 7-day running average WAS production, and solids discharged through the secondary effluent. (3) According to the original 1996 DWWTP Expansion project design criteria, RAS pumps were installed with sufficient capacity to pump 75% of the influent. There is no flow meter on the RAS flow, therefore, there is uncertainty about the true RAS flow rate. 75% was assumed for the development of the BioWin model. (4) The 2004 Advanced Treatment Upgrade design criteria reports a desired nitrified MLR flow range of 150%-200% of the influent. There is no flow meter on the mixed liquor return, therefore, there is uncertainty about the true MLR flow rate. 200% of the influent was assumed for development of the BioWin model. (5) Historical primary sludge concentration data was not available. Primary sludge load was calculated based on influent, primary effluent, and primary sludge flow data.
(6) The City measures the WAS flow by recording the amount of time the WAS pumps operate multiplied by their rated capacity.

Typically, a calibrated model exhibits an accuracy within a 10% margin of the historical calibration period data. The model has good agreement for key parameters, such as MLSS concentration, RAS concentration, and SRT. Also, the influent characteristics, primary effluent flow, secondary effluent flows, and solids production have a good calibration and are within the 10% margin. Primary effluent TSS concentration and load, secondary effluent BOD concentration, and secondary effluent nitrogen species concentrations are outside the desired range, however, for the purpose of evaluating treatment facilities in the master plan, the model is calibrated and sufficiently accurate. The discrepancy in these parameters could be due to variability in the process performance or operating conditions causing average values of historical data to not be representative of steady-state conditions. The following section summarizes deficiencies at the plant that could cause the model to overpredict plant performance.

3.4 Existing Plant Deficiencies
Chapter 1 presents the recent influent flows and loads. Appendix 3B shows the variability in operational data and performance and shows that the plant routinely struggles to maintain effluent compliance for BOD, TSS, and total nitrogen. As a result, the plant bypasses a portion of the influent to the Industrial WWTP to decrease loading to the DWWTP. Furthermore, while the process model developed for the CHAPTER 3 – EXISTING PLANT EVALUATION
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DWWTP matched historical data for most parameters, the model overpredicted other parameters.

Uncertainty around certain historical data as well as hydraulic and process deficiencies may cause a lack of consistent performance across basins and could result in averaged data values that are not representative of steady-state conditions.

The process deficiencies at the plant are:
 Biofilter recirculation wet well:
» Primary effluent, RAS, and MLR flows combine in the biofilter recirculation wet well, none of which are individually metered. The combined flow is then pumped to the anoxic basin. The combined anoxic basin influent is metered but the flow meter is installed at a high point in the line, which causes errors in the readings.
» The water level in the wet well varies quickly. If the water level in the wet well is too high, it can cause the primary sedimentation basin weirs to become submerged. If the water level is too low, it can cause the RAS pumps to over pump the sludge blanket and create a cone of mixed liquor that short circuits the sludge blanket.
 Anoxic and aerobic basins:
» The plant has a single anoxic basin that cannot be easily bypassed or taken out of service. The basin has not been drained since it came online around 2005. » The anoxic basin diffusers are beyond the end of their useful life, which is likely affecting oxygen transfer efficiency and ability to maintain a DO concentration. » A lack of mixers in the swing zones could cause solids to settle and accumulate in the anoxic basin.
» The geometry of the anoxic basin is asymmetrical and does not evenly feed the subsequent three aeration basins, which causes uneven solids inventory and performance across the three basins. » The aeration basins have not been taken offline or drained in several decades and the diffusers are beyond the end of their useful life, which is likely affecting oxygen transfer efficiency and ability to maintain a DO concentration.
» DO data appears skewed and changes abruptly after probes are recalibrated, indicating the DO may actually be lower than what the DO probes are reporting. » Low DO concentrations can contribute to poor settling (high sludge volume index (SVI)) in the sedimentation basins and insufficient oxygen to fully nitrify. » The blowers struggle to provide sufficient air flow to maintain necessary DO concentrations, particularly during high load events.
» The plant has been operating at higher SRTs and higher MLSS concentrations during the winter to increase nitrification rates. However, based on recent historical data, this operation is still not enough to fully nitrify during the winter, which indicates that the aeration basins do not have sufficient oxygen, bioreactor aeration volume, or both.  Secondary sedimentation basins and sludge pumps:
» The geometry of the mixed liquor channel causes an uneven flow distribution from the aeration basins to the secondary sedimentation basins. The clarifiers are fed through a submerged orifice in the channel that does not easily allow for monitoring and adjusting the feed across each clarifier.
» Uneven flow to the secondary sedimentation basins can disrupt settling, cause short-circuiting, dead zones, increased effluent TSS concentrations, and uneven sludge blanket depths.

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» Plant staff have observed better sludge blankets in secondary sedimentation basins #5 and #6 compared to the sludge blankets in basins #1-#4 due to their differences in depth (basins #5 and #6 are 13.2 feet deep and basins #1-#4 are 9.5 feet deep). The secondary treatment process mixed liquor has poor settleability, with high SVIs. The average SVI value from the 3-month calibration period was 137 mL/g, and the 90th percentile from the same period was 175 mL/g. The 90th percentile from the 2024 calendar year was 258 mL/g. Poor settling can cause permit violations and can be an indication of other process issues. » Currently there are no flow meters on the WAS or RAS lines. The lack of flow data causes uncertainties in calculating the SRT and makes it more difficult to troubleshoot and adjust setpoints to maintain stable operations.
» The configuration of the RAS and WAS piping causes uneven flow rates from each of the sedimentation basin sludge blankets.

The variable and inconsistent plant performance is likely causing historical average data to not be representative of steady state conditions. While the process model matches the influent wastewater characteristics well and is useful to determine future plant sizing and configuration, the lack of historical stable performance made it difficult to develop a well calibrated process model that determines current capacity based on existing operations. Additionally, some uncertainty around the historical data further complicated developing a calibrated model. For example, for the model to match the historical DO data and effluent nitrogen concentrations, the kinetic parameter for the nitrification rate in the model was lowered. However, inconsistent loading across aeration and sedimentation basins and inaccurate DO data could be the actual inhibitor of nitrification rather than a difference in a kinetic characteristic of Tulare’s wastewater.

3.5 DWWTP Plant Capacity

3.5.1 Historical Plant Capacity
The 1996 DWWTP expansion project increased the plant’s design capacity to 6 mgd and was designed for influent concentrations of 181 mg/L of BOD and 178 mg/L of TSS. Based on the information presented in the City’s WDR (Order R5-2013-0019), the DWWTP has experienced challenges operating at the 6 mgd design capacity for several years.

In 2006, the City completed the DWWTP Advanced Treatment Upgrade project, which added an anoxic basin designed for nitrogen removal to 10 mg/L or less. Based on the WDR, the plant started to experience nitrogen removal fluctuations, primarily during the cold weather seasons when effluent total nitrogen concentrations were above the annual average.

In 2010, the City completed another DWWTP upgrade and expansion project, which added an influent pump station, headworks screening, and grit removal, and “increased” the design flow to 6 mgd. However, no biological treatment capacity was added at the DWWTP. Rather a bypass line was installed at the DWWTP headworks to shunt flow to the Industrial WWTP, reducing the load treated through the DWWTP.

The headworks has a rated capacity of 16 mgd, which matches the projected peak hour flow for the planning horizon. Therefore, the headworks has sufficient capacity to serve the plants needs and does not need to be modified or expanded as part of the plant expansion.

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A capacity evaluation was performed in 2013 to satisfy provisions of the City’s WDR. The 2013 study estimated that the DWWTP capacity was lower than 6 mgd (approximately 5.2 mgd at annual average daily flow [AADF] and 5.5 mgd at average daily maximum month flow [ADMMF]) due to increases in influent BOD, TSS, and TKN concentrations and as well as limitations in the DWWTP’s aeration system, which has not since been updated. Shortly after the completion of the 2013 study, several operational changes were made to the DWWTP, including restoring operation of the plant’s biofilters. Another capacity evaluation was completed in 2017, which estimated the plant’s capacity at 5.5 mgd AADF and

5.8 mgd ADMMF. Since the 2017 study, influent flows have remained stable, but influent BOD and TSS concentrations have increased by approximately 26 percent and 40 percent, respectively (refer to Chapter 1 for influent flows & loads analysis). Furthermore, the biofilters are no longer in service due to poor condition, which further limits the treatment capacity of the plant.

Water conservation over the last 15 years has led to a slower increase or often even a reduction in domestic wastewater flows. However, influent concentrations continue to increase. Based on the high strength max month influent wastewater concentrations presented in Chapter 1, the flow capacity of the plant has decreased compared to previous capacity evaluations in 2013 and 2017. However, the load capacity (e.g., pounds per day of influent BOD, TSS, and TKN) has remained similar.

3.5.2 Existing Plant Capacity
Based on historical loading and performance, recommended criteria were developed for each major treatment process to support the existing plant capacity evaluation. The historical load and performance of each unit process were compared with the original design criteria and with typical expected performance. From this analysis, recommended criteria were established for use in the capacity assessment.

Table 3.4 summarizes the performance of each unit process along with the recommended capacity criteria for the existing plant. Appendix 3B provides graphs of historical performance, including effluent discharge relative to the plant NPDES permit limits. A capacity analysis for the solids handling processes was not conducted because the units have been offline for several years and historical data was not available.

Furthermore, given the mechanical and structural condition of the solids handling unit processes, representative capacity criteria values would be highly uncertain.

Table 3.4 Unit Process Performance and Capacity Criteria Process Design
Parameter
Units Original Design
Capacity
Average
Performance
from 2019 –
2024(1)
Typical Design
Values(2)
Criteria Used for
Capacity
Analysis
Influent Pump
Station
Flow Rate mgd 16.0 firm

21.3 installed

4.2 AAF

11.8 PHF
Sufficient firm
capacity (N+1) at
PHF
Sufficient firm
capacity (N+1) at
PHF
Rake Screens Flow Rate mgd 16.0 firm

32.0 installed

4.2 AAF

11.8 PHF
Sufficient firm
capacity (N+1) at
PHF
Sufficient firm
capacity (N+1) at
PHF
Vortex Grit
Removal
Flow Rate mgd 16.0 installed 4.2 AAF

11.8 PHF
Varies Sufficient
installed capacity
at PHF
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Process Design
Parameter
Units Original Design
Capacity
Average
Performance
from 2019 –
2024(1)
Typical Design
Values(2)
Criteria Used for
Capacity
Analysis
Primary
Sedimentation
Basins
Overflow Rate
at AAF
gpd/sf 1,046 703 800 – 1,200 1,046
Overflow Rate
at PHF
gpd/sf 2,490 1,993 2,000 – 3,000 2,490
TSS Removal
at AAF
% 59 66 50 – 70 59
PE TSS
Concentration
mg/L -- 101 varies 101
Aeration Basins Minimum Month
Temperature
C -- 15 varies 15
aSRT d 4.8 4.5 varies 8 in winter(3)

3.5 in summer
SVI mL/g -- 136 average--
175 90th
percentile
150 150
MLSS mg/L 2,800 2,737 varies 2,800(4)
Process
Aeration
scfm 4,050 3,007 average
4,030 max
month
varies Sufficient
installed capacity
at peak day load
Secondary
Sedimentation
Basins
SOR at AAF gpd/sf 565 395 400 – 800 395(5)
SOR at PHF gpd/sf 1,345 1,120 1,000 – 1,200 900(5)
SLR at AAF lb/d/sf -- 16.3 20 – 30 16(5)
SLR at PHF lb/d/sf -- -- 35 – 40 35(5)
Notes:
(1) All basins have been in service throughout the period from which historical data values are reported. (2) Typical design values taken from WEF Manual of Practice No. 8 (MOP-8) textbook, Design of Water Resource Recovery Facilities.
(3) The recommended criteria for aSRT is higher than the historical design criteria value due to recent wastewater data showing cooler minimum month wastewater temperatures and using a higher nitrification safety factor (around 3.5) to account for uneven flow splits between basins and poor oxygen transfer from aging diffusers. (4) Criteria value for MLSS is based on the capacity criteria SVI of 150 mL/g. Degraded settleability (higher SVIs) will lower the allowable MLSS and reduce the capacity of the plant.
(5) Criteria value for SOR and SLR are needed to prevent solids breakthrough in the final effluent; based on the capacity criteria SVI of 150 mL/g. Degraded settleability (higher SVIs) will lower the allowable MLSS and reduce the capacity of the plant.

Table 3.5 presents the estimated capacity for each unit process based on the recommended capacity criteria. AADF and PWWF capacity is developed for each unit process assuming all units in service. The anoxic basin, aeration basins, and secondary sedimentation basin basins constitute the secondary treatment system and is assigned the same capacities, as these processes are integral to each other and depend on several factors, including SRT, MLSS concentration, SVI, temperature, and flow distribution. The primary sedimentation basins and secondary treatment system do not have sufficient capacity for the CHAPTER 3 – EXISTING PLANT EVALUATION
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plant expansion. The secondary treatment system capacity is lower than the previous design values. One reason is the poor oxygen transfer through the aeration system that results in lower DO concentrations, poor settleability, and higher mixed liquor concentrations, all of which negatively impact capacity.

Replacing the diffusers and operating at a higher DO concentration may help recover some capacity.

Table 3.5 Unit Process Capacity Ratings
Process Controlling Condition Capacity, mgd Projected 2043 Flow, mgd
Capacity Deficit, mgd
Influent Pump Station PHF 16 16 0
Screens and Grit
Removal
PHF 16 16 0
Primary Sedimentation
Basins
PHF
AAF

14.7 6.2
16 6.8

1.3 0.6
Secondary Treatment
System(1)
PHF
AAF (Winter)
AAF (Summer)
6 2.5

4.2 16

6.8 6.8
10 4.3

2.6 Notes:

AB - table notes abbreviations; BC - table notes abbreviations (1) Estimated capacity based on max month load conditions, an aSRT of 8 days, temperature of 15 degrees Celsius in winter and an aSRT of 3.5 days and temperature of 25 C in summer, SVI of 150 mL/g, and a PHF/AAF peaking factor of 2.4.

The secondary sedimentation basin capacity is based on its ability to settle sludge which is dependent on the MLSS concentration and SVI. State point analysis was performed for an SVI of 150 mL/g. State point analysis was used to estimate the PHF capacity over a range of recommended MLSS and settleability conditions. The PHF capacity was converted to an equivalent AAF capacity using a PHF/AAF peaking factor of 2.4. Figure 3.2 shows the Aeration Tank and Secondary Sedimentation Basin AAF capacity over a range of SRT, MLSS concentration, temperature, and an SVI of 150 mL/g. During the summer months when temperatures are warmer, the plant has more biological capacity to treat maximum month loading conditions due to the need for a shorter aSRT to fully nitrify. The minimum month temperature limits the capacity of the secondary system and represents a worst-case scenario. The recommended capacity rating for the secondary facilities is 2.5 mgd AAF (6 mgd PHF) during minimum month temperatures and 4.2 mgd AAF (10 mgd PHF) during max month temperatures, which represents the intersection of the aSRT line and the Secondary Sedimentation Basin capacity line estimated from the SVI of 150 mL/g. If the settleability were degraded, then the capacity would be reduced.

CHAPTER 3 – EXISTING PLANT EVALUATION
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 3-12
Figure 3.2 Secondary Treatment System Capacity All Aeration Tanks and Clarifiers in Service The existing plant is insufficient for the future capacity needs. Expanding capacity of the existing plant would not only require complicated modifications to aging infrastructure, which introduces uncertainty regarding its feasibility, but would also fail to address many of the hydraulic and process deficiencies described previously. Also, the space available for future expansion does not allow for symmetrical layout of aeration basin facilities and does not consider feasibility of future expansions. The next chapter discusses the alternatives evaluated to provide additional plant capacity.

CHAPTER 4 – ALTERNATIVES ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-1
CHAPTER 4 ALTERNATIVES ANALYSIS

4.1 Introduction
Chapter 3 determined that the existing plant is insufficient to handle flows and loads within the planning horizon. Carollo conducted a preliminary analysis and selected six potential expansion alternatives to address future plant capacity needs and effluent quality deficiencies that exist at the current plant. Based on input from the City, three plant expansion treatment alternatives were selected for in-depth analysis and evaluated to determine the most cost-effective, reliable, and robust plant expansion configuration.

This chapter summarizes the following project efforts:
 Alternatives screening.
 Description of common improvements needed for the plant expansion.  Description and comparison of secondary treatment technology alternatives.  Financial evaluation.
 Recommended improvements and implementation.

4.2 Alternatives Screening
On August 20, 2025, during a collaborative workshop, Carollo presented a list of six potential plant expansion alternatives for the City’s consideration. These alternatives varied in their use of existing DWWTP infrastructure, ranging from expanding the existing treatment plant to constructing entirely new treatment trains. Only well-established and widely used biological treatment processes, and those that best align with the City’s operations and maintenance needs were considered. The City identified no foreseeable drivers for evaluating emerging treatment technologies that have not yet been demonstrated at full-scale domestic wastewater treatment plants.

During the workshop, the City provided feedback for each alternative and shortlisted three alternatives for Carollo to evaluate in detail. Table 4.1 summarizes the alternatives and identifies which alternatives were selected for detailed analysis.

CHAPTER 4 – ALTERNATIVES ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-2
Table 4.1 Plant Expansion Treatment Alternatives
# Alternative Name Description City Feedback (1)
1 Expand Existing DWWTP  Construct additional primary clarifiers, aeration basins, and secondary clarifiers, similar to existing.
 Rehab existing boilers, heat exchangers, digesters,
and gravity belt thickener.
 Add dewatering, waste gas flare, and thickening
redundancy.

Do not evaluate further.

City has no desire to expand
existing plant. It would not
address fundamental issues
with performance or
hydraulics.
2 Convert Existing DWWTP
to MBR Facility
 Construct additional primary clarifiers, similar to
existing.
 Convert secondary clarifiers to MBR tanks.
 Rehab existing boilers, heat exchangers, digesters,
and gravity belt thickener.
 Add dewatering, waste gas flare, and thickening
redundancy.

Do not evaluate further.

This alternative would be an
improvement but not sufficient
in solving other plant
challenges regarding
performance, hydraulic
concerns, risks, and
construction constraints.
3 Greenfield: PC/MLE
Process/SC
 Construct new primary treatment, secondary
treatment, and solids handling systems, including
primary clarifiers, bioreactors, secondary clarifiers,
digesters, thickening, and dewatering.
 Abandon existing DWWTP liquid stream facilities.

Do not evaluate further.

This alternative would require
high (LCC) and regulatory
requirements in rehabilitating,
maintaining, and expanding
the thickening, digestion, and
gas handling facilities.
4a Greenfield: Secondary only
(MLE Process)
 Construct new secondary treatment and solids
handling systems, including bioreactors, secondary
clarifiers, and thickening
 Abandon existing DWWTP liquid stream facilities.

Evaluate in detailed
analysis.
4b Greenfield: Secondary only
(MBR)
 Construct new secondary treatment and solids
handling systems, including bioreactors,
membrane tanks and associated ancillary facilities,
and thickening.
 Abandon existing DWWTP liquid stream facilities.

Evaluate in detailed
analysis.
4c Greenfield: Secondary only
(Oxidation Ditch)
 Construct new secondary treatment and solids
handling systems, including oxidation ditches,
secondary clarifiers, and thickening.
 Abandon existing DWWTP liquid stream facilities.

Evaluate in detailed
analysis.

Notes:

DWWTP - Domestic Wastewater Treatment Plant; LCC - ;life cycle costs (1) Feedback and alternative selections were based on discussions with City staff during August 20, 2025 workshop.

CHAPTER 4 – ALTERNATIVES ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-3
Key Decisions/Assumptions for plant expansion planning:
 Existing infrastructure issues such as bottlenecked hydraulics, struggling treatment performance from existing processes, lack of redundancy, and aging equipment led to the agreement that the greenfield expansion alternatives are most suitable.
» Moving forward, all alternatives will construct a new treatment train in the available space to the West that, at full buildout, will treat 2043 projected influent flows and loads from the existing headworks.
» The alternatives analysis will consider full plant expansion to treat the projected flows and loads as the basis for selecting the preferred secondary treatment technology. Once the secondary treatment technology is selected, a phased implementation could be considered as a way to reduce near-term construction cost.
 The City maintains a third-party contract to beneficially use digester gas produced from the DWWTP and neighboring IWWTP through a cogeneration process. However, the DWWTP has produced very little to no gas in the last several years because the digester heating equipment has not been functional. During the workshop, the City decided digester gas from the DWWTP may not be required in the long-term and the cost to construct, operate, and maintain additional primary clarifiers, digesters, boilers, heat exchangers, flares, and thickeners would be onerous and cost prohibitive. » The alternatives analysis shall evaluate processes without primary treatment or digestion/gas handling.
» The plant expansion could include the option to route sludge to the industrial plant to provide additional gas production if desired.
 The listed rated capacity of the headworks is beyond the projected peak hour flows. » New headworks facilities are not considered as part of the plant expansion.  New administrative building should be included as part of the plant expansion.  The full buildout plant expansion will have the capacity to fully treat all influent flows and will no longer rely on diverting flows to the IWWTP. Additionally, the plant expansion does not consider receiving any return loads from the IWWTP.

4.3 Plant Expansion Common Improvements
There are several shared improvements that the DWWTP would need for the plant expansion regardless of the selected treatment alternative. These common improvements are presented in this section separately from the secondary treatment alternatives to highlight the facility’s baseline needs and to focus subsequent discussions purely on the comparative differences of the treatment technologies.

4.3.1 Solids Handling Improvements
The three selected alternatives produce slightly different quantities and level of stabilization of WAS, however, the processes and equipment sizing needed to handle the WAS from each treatment technology would be nearly the same. Therefore, a single recommended solids handling process was applicable across all three alternatives. Figure 4.1 presents the preliminary solids handling process flow diagram for the plant expansion.

CHAPTER 4 – ALTERNATIVES ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-4
Figure 4.1 Solids Handling Process Flow Diagram
The core concept of the recommended solids process is to leverage, optimize, and upgrade the plant’s current solid handling infrastructure for future expansion. As shown in Figure 4.1, WAS from the plant’s secondary process is pumped into sludge holding tanks at around 0.5 percent total solids (TS). A recirculation stream from the tanks feeds the thickening equipment, which returns thickened waste activate sludge (TWAS) to the tanks at around 5 percent TS. This process targets a TWAS solids percentage of 3 percent TS to then feed the sludge drying beds. This method of recuperative thickening provides added flexibility in operations, as it allows for thickening equipment to operate only when needed and decouples the plant’s WAS rate from the rate at which the drying beds are fed. Aeration and mixing are needed in the sludge holding tanks to provide a consistent feed to thickening and to prevent septic conditions from occurring in the tanks.

4.3.2 Common Improvement Descriptions and Site Layout
Table 4.2 describes the plant expansion common improvements and lists considerations for preliminary design. Figure 4.2 depicts a planning level site layout for these common improvements.

CHAPTER 4 – ALTERNATIVES ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-5
Table 4.2 Common Improvements
Improvement Description Considerations/Notes (1)
Admin Building Construct new admin building to serve as a central operations building for both the DWWTP
and IWWTP, providing updated space needs to
accommodate the a plant laboratory, SCADA
control room, workspaces, larger meeting/break
rooms, and other essential support
infrastructure.

City is considering constructing a new
Corporation Yard across the street (Northeast of
the plant), which may be the preferable location
for the new admin building. Per request from the
City, a high-level budgetary cost for the admin
building is included in the plant expansion total
project cost, however, it may fall under a
separate City project budget in the future. It is
recommended that specific features of the
building, including construction material and
architectural finish, lab equipment, number and
size of offices and conference rooms, are
determined during preliminary design.

Electrical Building Construct new electrical building to house new electrical equipment (e.g., transformers, MCCs,
PLCs, etc.). Also, new electrical building may
replace/relocate electrical equipment within
existing admin building.

Size and scope of specific electrical equipment
should be determined during preliminary design.

Electrical equipment scope will depend on the
selected treatment alternative.

Influent Splitter Box Construct new hydraulic structure downstream of the existing headworks to divert flow to the new
plant and split flow between existing plant and
new plant if necessary.

N/A
Secondary Effluent
Pump Station
Rehab
Pump replacement and structural rehab to
secondary effluent pump station based on
findings from the condition assessment.

Modifications to the secondary effluent pipeline
or effluent weir boxes may be needed depending
on plant water needs for the DWWTP, IWWTP,
and future recycled water production. It is
recommended that the scope of these
modifications is refined during preliminary
design.

Plant Drain Pump
Station
Construct new plant drain pump station to pump
storm water, thickening filtrate, decant from
drying beds, and other miscellaneous return
flows back to the influent pump station.

Size and location to be determined during
preliminary design and may vary slightly
depending on recommended treatment
alternative.

Convert Digesters
to Sludge Holding
Tanks
Convert both existing digesters to sludge holding
tanks. Includes removing floating covers, filling in
conical bottom with concrete, and installing
mixing & aeration systems.

Preliminary design requires further investigation
whether to repurpose/rehab or demolish
mechanical piping around digesters.

Constructing new lined aerated sludge lagoons
could be considered in lieu of sludge holding
tanks.

CHAPTER 4 – ALTERNATIVES ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-6
Improvement Description Considerations/Notes (1)
Solids Thickening
Upgrade
Install two new thickeners with thickened sludge
pumps, polymer feed system, and other ancillary
equipment under a shade structure.

Alternative thickening technologies (e.g., RDTs)
or optimizing the existing GBT can be evaluated
further during preliminary design. The City could
rehabilitate the existing GBT and add a second
skid for redundancy within the existing biosolids
building (City should confirm functionality of
existing GBT unit if this is pursued). Also,
additional investigation is needed on the roof of
the biosolids building to determine structural
integrity.

Sludge Drying Bed
Rehab
Replace decant gates, decant pump station
pumps, and rehabilitate drying bed liners.

Access to drying beds and inspection was limited
due to site conditions. Further investigation is
required to determine extent of rehabilitation
necessary. Alternative liners should be evaluated
including soil-cement, asphalt, concrete, etc.

Notes:

RDT – rotary drum thickeners; PLC – programmable logic controller. (1) Opportunities for the scope of a project element to evolve or be refined due to selected technology alternative, future decisions, or findings from further investigation.

CHAPTER 4 – ALTERNATIVES ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-7
Figure 4.2 Common Improvements Planning Level Site Layout CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-8

4.4 Technology Overview
This section describes each of the proposed secondary treatment processes in greater detail. All three alternatives employ a ‘suspended growth activated sludge’ process, which uses suspended biomass to consume BOD and nitrogen, followed by a physical separation step to control effluent TSS. Solids separated from the process are sent back to the front of the secondary process as RAS to maintain a designated biomass population. Excess solids are treated and disposed of as waste activated sludge (WAS).

A BioWin process model was developed for each of the alternatives to estimate the required dimensions of their secondary treatment and solids handling systems. For this planning level stage, each process was sized to achieve a maximum month effluent concentration of 30 mg/L for BOD, 30 mg/L for TSS, and 10 mg/L for TN.

4.4.1 MLE
The MLE process is one of the most common conventional activated sludge configurations for Biological Nutrient Removal (BNR) and is currently utilized by the existing DWWTP. Figure 4.3 shows the process flow diagram for a new greenfield wastewater treatment plant with the MLE process. The following is a list of new infrastructure that would be needed for this alternative, not including the common improvements:
 4 rectangular bioreactors.
 2 circular clarifiers.
 Mixed liquor pump station.
 Mixed liquor splitter box.
 RAS/WAS pump station.
 Blower building.

Figure 4.3 MLE Alternative Process Flow Diagram
CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-9
After passing through the headworks, influent enters a large concrete tank or ‘bioreactor’ in an un-aerated or ‘anoxic’ zone and is combined with RAS from the clarifiers and MLR. The combination of RAS and influent is referred to as mixed liquor (ML).

Under anoxic conditions lacking oxygen, denitrifying bacteria utilize carbon from the influent BOD to reduce nitrate from the RAS and MLR into nitrogen gas, which releases into the atmosphere. After the anoxic zone, blowers provide air through fine bubble diffusers in the aerobic zones of the bioreactor.

Aerobic bacteria begin to dominate and consume BOD. This zone also promotes nitrifying bacteria, which use oxygen to convert influent ammonia into nitrate. After passing through the aerobic zone, the mixed liquor exits the bioreactor. A portion is sent to clarifiers for solids separation, and the rest is pumped to the anoxic zone of the bioreactor to circulate nitrate for removal. Typical MLR rates are about four times the influent flow.

The basis for analysis assumes circular secondary clarifiers. Circular clarifiers require more footprint because they don’t benefit from common wall construction that rectangular clarifiers do. However, maintenance for circular clarifiers is expected to be lower than rectangular clarifiers because there is only a single drive mechanism that is accessed above the water and doesn’t require chain tensioning like the rectangular clarifiers. Circular clarifier mechanisms typically have longer useful lives before replacement or rehabilitation. Further analysis and selection of clarifier technology can be determined during preliminary design.

Mixed liquor sent to the circular clarifiers is piped into the middle of the tank, and as the flow moves radially outward the velocity is slowed down and solids in the mixed liquor drop out of suspension. The clarified effluent flows over a weir at the outer perimeter that drains to the secondary effluent pump station. Solids that settle to the bottom of the clarifier are the ‘activated sludge’ and are collected by a sludge scraper mechanism and recycled back to the anoxic zone as RAS. The circular scraper also removes floating debris from the surface of the water such as scum that is pumped either to the anoxic zone or the sludge handling process.

Figure 4.4 shows the proposed site layout.

CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-10
Figure 4.4 MLE Alternative Site Layout

4.4.2 MBR
The MBR process is similar to the MLE process but replaces the secondary clarifiers with membrane tanks.

Figure 4.5 shows the process flow diagram for a new greenfield wastewater treatment plant with the MBR process. The following is a list of new infrastructure that would be needed for this alternative, not including the common improvements:
 Fine screens.
 3 rectangular bioreactors.
 Mixed liquor pump station.
 Mixed liquor splitter box.
 MBR tanks and membrane cassettes.
 Clean-In-Place chemical storage and feed system.
 RAS/WAS pump station.
 Permeate and backwash pump station.
 Blower building (process and air scour blowers).

CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-11
Figure 4.5 MBR Alternative Process Flow Diagram
The membrane tanks are separate aerated chambers with cassettes of hollow fiber membrane tubes.

Permeate pumps pull water through the membrane into the center of the hollow fiber tubes, which collects in a header pipe, leaving solids in the tank. The membranes require a 2-millimeter perforated opening fine screen in addition to the existing rake screens at the headworks to protect the cassettes.

To keep the membrane surfaces clean of solids buildup, the tanks have dedicated air scour blowers that pump coarse bubbles to physically remove solids from the membrane fibers. Additionally, backwash pumps periodically send clean water to reverse the flow through the fibers to slough solids from the membranes. Despite the constant air scour and backwash, the membranes still lose permeability over time and can develop mineral scaling, so they require clean-in-place (CIP) chemical washes with sodium hypochlorite. CIPs can be done automatically based on transmembrane pressure (TMP). As the membranes get clogged, the pressure across them increases. Once the pressure reaches a setpoint, a CIP routine will trigger to remove solids buildup. A separate CIP chemical wash using citric acid is required annually, where the basins are taken offline and membranes soaked for several hours to dissolve scaling.

Membrane cassettes are additionally removed from the tank for inspection as a part of this routine maintenance.

Like the MLE system, this process also includes a flow path that recycles to the beginning of the bioreactor to retain biomass and bring nitrate to the anoxic zone. RAS is returned from the membrane tanks to the anoxic zone. RAS flow rates for the MBR process are typically much higher than for conventional MLE; anywhere from two to six times the influent flow rate. Depending on the wastewater characteristics, a separate MLR stream may or may not be necessary. Due to the physical separation of solids, rather than relying on gravity to achieve settling, the membranes allow for a much higher loading rate to achieve solids separation. Therefore, the membrane tanks operate at a much higher (MLSS) concentration, typically more than twice that of an MLE process, which results in much smaller bioreactor tanks.

CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-12
The MBR process requires a significant amount of supporting ancillary facilities, which are located in an equipment gallery. This gallery sits beneath a shade canopy structure that includes the permeate pumps, CIP feed pumps, membrane maintenance area, bridge cranes, RAS and WAS pumps, membrane air scour blowers, and the membrane tanks.

Figure 4.6 shows the proposed site layout.

Figure 4.6 MBR Alternative Site Layout

4.4.3 Oxidation Ditch
The oxidation ditch (ox ditch) is the process with the least amount of equipment and the largest footprint of the alternatives. Figure 4.7 shows the process flow diagram for a new greenfield wastewater treatment plant with the oxidation ditch process. The following is a list of new infrastructure that would be needed for this alternative, not including the common improvements):
 2 oxidation ditches.
 2 circular clarifiers.

CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-13
 Mixed liquor splitter box.
 RAS/WAS pump station.

Figure 4.7 Oxidation Ditch Process Flow Diagram
Biomass is retained in an ovular, racetrack-like tank. Surface aerators both maintain a high enough water velocity to prevent solids from settling out and introduce oxygen into the water via splashing. One end of the tank has an extended/squared portion which operates as the anoxic region of the ox ditch. ML is introduced to this area by a gate at the side of the tank which diverts a fraction of what goes around the racetrack. Ox ditches maintain a larger solids inventory and longer SRT than the other alternatives, which results in larger tanks, but also a more stable process that better attenuates influent variability or shock loads.

Ox ditches have low O&M requirements. Aerator speed, mixed liquor return gate opening, and weir gate position are infrequently adjusted to maintain appropriate operational parameters for dissolved oxygen and nitrate concentration. Compared to the other alternatives, the process has much less equipment because it does not require diffusers, blowers, or MLR pumps.

Mixed liquor exits the ox ditch through a downward opening weir gate that is then fed to circular secondary clarifiers, like the MLE alternative. Solids that settle out of in the secondary clarifiers are returned to the anoxic zone or wasted to the solids handling process.

Figure 4.8 shows the proposed site layout.

CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-14
Figure 4.8 Oxidation Ditch Alternative Site Layout

4.4.4 Comparison of Alternatives

4.4.4.1 Design Criteria
Table 4.3 below summarizes important design criteria for each of the alternatives. A few design criteria are worth discussing further:
 MLSS Concentration:
» MLE operates close to how the DWWTP currently operates, at 2,800mg/L, the ox ditch operates slightly higher at 3,800 mg/L, and the MBR sees 8,500 mg/L MLSS in its bioreactor and upwards of 10,000 mg/L in the membrane tanks.
» This difference is key in the resulting total volume of each alternative. Operating the ox ditch at a higher MLSS requires larger clarifiers when compared to MLE, but allows the ox ditch bioreactor volume to be smaller than it otherwise would need to be with a lower MLSS. MBR allows for a significantly more compact site layout due to a higher concentration of biomass.

CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-15
 Footprint:
» The footprint should consider the feasibility of future expansion beyond what is planned in this report. The long oxidation ditch footprints require basins to be oriented east/west compared to the north/south flow path of the other alternatives, requiring additional land for expansion. The north/south flow path is more efficient in fitting between the boundary of the road to the north and the solar field to the south, while allowing sufficient room to the west for future expansion.

Alternatively, the ox ditch could have a folded racetrack configuration to fit north/south, but that is more expensive to construct due to additional curved walls. The City indicated that the solar panels south of the proposed secondary improvements will likely be able to be removed by the time another plant expansion is required, alleviating the next expansion’s spatial constraints.  SRT & WAS Production:
» Another important design criterion to highlight is the relationship between SRT and WAS load.

Longer SRTs lead to increased breakdown of volatile solids in the system, which leads to fewer solids wasted from the system. This results in smaller thickener units or shorter run times, less polymer consumption, increased capacity in the sludge drying beds, more stabilized solids that lessen odor issues, and lower hauling costs. The oxidation ditch has the highest SRT and thus sees the greatest benefit of stabilized solids when compared to the other alternatives.

Table 4.3 Summary of Design Criteria for Secondary Treatment Alternatives Parameter Units MLE Process MBR Oxidation Ditch
Bioreactors number 4 3 2
Volume, each MG 1.6 0.9 4.3
Volume, total MG 6.4 2.8 8.7
Side Water Depth ft 15 15 18
Anoxic Volume % 20% 25% 20%
Air flow scfm 11,500 13,000 n/a
Blower/Aerator, tot HP 400 875 1200
MLSS mg/L 2,800 8,500 3,800
Aerobic SRT days 6 10 16
Clarifiers number 2 N/A 2
Clarifier Diameter ft 110 N/A 125
WAS load dry lb/d 19,000 16,400 15,300
Notes:

HP – horsepower; lb/d- pounds per day; MG – million gallon; mg/L – milligrams per liter; scfm – standard cubic feet per minute.

4.4.4.2 Operations and Maintenance
Each of the proposed technologies varies in its level of operational requirements and complexity and are worth discussing further. Listed below are relevant operational considerations for each treatment process.  MLE:
» This system would be the most familiar for plant staff, with modernized controls and streamlined process flows improving operations.

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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-16
» Circular secondary clarifiers would have lower maintenance than the existing rectangular clarifiers require.
» Having operational redundancy in the aeration basins would allow operators to take basins offline to clean diffusers which is recommended every couple of years, increasing oxygen transfer in the bioreactors and restoring treatment efficacy.
 MBR:
» Weekly membrane chemical CIP processes are automated based on operational setpoints, only requiring the upkeep of chemical supplies.
» Increased mechanical upkeep for air scour blowers, permeate pumps, fine screens, and annual membrane inspection and CIP would add new important oversight from plant staff. » Solids separation is a physical barrier, so the process is not impacted by solids settleability; the membranes act as an effluent quality guarantee.
» Membrane cassettes need to be replaced approximately every 10 years. The City would need to budget for the equipment replacement cycle and consider a staggered replacement plan for various trains. Membrane replacement and annual inspections require taking trains offline, which should consider redundancy requirements and seasonal flow variations to ensure treatment goals are met during maintenance cycles.
 Ox Ditch:
» The ox ditch has the least amount of mechanical equipment, with only surface aerators, mixed liquor return gates, effluent weirs, and clarifier mechanisms. » Long SRT (16 days) and large bioreactor volume allow for significant attenuation of influent variability. Negative impacts of performance, equipment failure, influent spikes, or other will be felt the least by an ox ditch.
» The lack of diffused aeration at the bottom of the tank more likely allows grit to settle out and accumulate in the basin. While not significantly detrimental to treatment, the ox ditch basin may benefit from being drained and grit removed at least every ten years or so.

4.4.4.3 Recycled Water Impacts
In parallel to this project, Carollo and the City are conducting a recycled water feasibility study. That project is coordinating with the Division of Drinking Water (DDW) to seek approval for soil aquifer treatment (SAT), where groundwater extracted downgradient of the effluent percolation ponds meets Title 22 filtration and disinfection requirements. If the DDW accepts SAT as an approved filtration process, then the selection of the secondary treatment process will not affect the treatment requirements for the recycled water analysis. However, if DDW does not accept SAT as an approved filtration process, a dedicated mechanical filtration process will be required to meet Title 22 requirements for recycled water, of which MBR is an approved technology. MLE and ox ditch would require a separate filtration process, such as cloth disk filters, to meet recycled water quality standards. Regardless of the secondary treatment technology selected, the City would then need to add a disinfection process, such as chlorination or ultraviolet disinfection, to meet Title 22 tertiary disinfected recycled water quality standards. Because it is not clear whether SAT will be approved as meeting filtration requirements, the Facility Plan analysis does not quantify the benefit of improved effluent quality from the MBR alternative. Additionally, the recycled water analysis is considering flows from the IWWTP as well.

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FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-17

4.5 Financial Evaluation

4.5.1 Cost-Estimating Methodology
Class 5 cost estimates were developed for the three shortlisted plant expansion alternatives and common improvements. Per AACE International (Association for the Advancement of Cost Engineering), class 5 estimates are typical for planning level projects and offer cost accuracy within -50 percent to +100 percent of the final project cost. The cost estimates for the plant expansion were developed through a detailed analysis, incorporating relevant unit costs with quantity takeoffs for various aspects (i.e., tank dimensions, construction materials, etc.). Key pieces of mechanical equipment were sourced directly from manufacturer budgetary quotations.

4.5.1.1 Capital Costs
Each capital cost estimate includes cost allowances for items with an undefined scope at this planning stage, with further definition deferred to the detailed design phase. Costs for items such as mechanical equipment installation, yard piping, site grading (asphalt or landscaping), and electrical, instrumentation, and controls (EI&C) equipment were estimated by applying a percentage allowance to the direct cost subtotal. In addition to direct cost allowances, construction cost factors and project cost factors were applied to estimate the Total Construction Cost and Total Project Cost, respectively. The allowances and cost factors are summarized below in Table 4.4.

Table 4.4 Capital Cost Factors
Cost Factors Applied To: Factor
Direct Cost Allowances
Site Work and Yard Piping Direct Costs 10%-15%
Metals Direct Costs 5%
Electrical, Instrumentation & Controls Direct Costs 20%-25% Total Direct Cost (TDC)
Construction Cost Factors
Escalation to Mid-Point (5% per yr for 3+ yrs) TDC 17.65% Sales Tax 50% of Previous Subtotal 8.25%
General Conditions Previous Subtotal 15%
Contractor Overhead, Profit, Risk Previous Subtotal 20% Estimating Contingency Previous Subtotal 35%
Total Construction Cost
Project Cost Factors
Engineering, Permitting, Administrative,
Construction Management
Total Construction Cost 25%
Total Project Cost
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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-18

4.5.1.2 O&M Costs
Annual O&M costs were estimated for each alternative. These costs were developed by quantifying the annual usage and requirements for labor, polymer, electric power, solids hauling, chemicals, and equipment maintenance, and is projected over 20 years from the estimate date, accounting for inflation.

Table 4.5 below details unit costs used to develop yearly O&M costs.

Table 4.5 O&M Cost Factors
O&M Item Unit Cost (2025 dollars)
Labor $/hr $ 50.00
Polymer $/lb active $ 3.50
Power $/kWh $ 0.25
Equipment Maintenance
(applied to equipment direct capital cost)
% 5%
Hauling $/WT $ 75.00
Citric Acid $/gal $ 16.00
Sodium Hypochlorite $/gal $ 3.50
Gal – gallon; hr – hour; kWh – kilowatt hour; WT – wet ton.

4.5.1.3 Life Cycle Costs
LCC were developed using the initial capital project costs and the 20-year annual O&M costs to provide a long-term financial estimate of each alternative. An annual escalation rate of 3percent was assumed for O&M unit costs, and a discount rate of 5 percent was applied to calculate the present value of all costs in 2025 dollars.

4.5.2 Financial Evaluation Results

4.5.2.1 Plant Expansion Capital Costs
Common Improvements
As mentioned previously, the common improvements encapsulate upgrades that would be needed regardless of the secondary treatment alternative. O&M costs for the common improvements were not estimated since all common improvements apply to all three alternatives and would not impact the decision-making process for selecting a recommended treatment process. Common improvements cost assumptions as well as opportunities to reduce capital costs are presented in a later section.

The costs presented below assume the full buildout capacity of 7.1 mgd, which is estimated to serve the plant capacity needs through 2043. Comparison of LCC is needed to select a recommended treatment alternative throughout the planning horizon and allocate budgets as part of a preliminary (CIP) plan.

However, if necessary, the selected alternative could be constructed in phases to reduce initial capital costs. A description of phased implementation is described in a later section.

Figure 4.9 visually illustrates the common improvements cost estimate, and Table 4.6 tabulates the costs that build it.

CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-19
Costs are shown as Total Project Costs.

Figure 4.9 Capital Costs – Common Improvements
Table 4.6 Common Improvements Capital Costs
Element Construction Cost (Million $) Project Cost (Million $) Admin Building $ 11.9 $ 14.8
Electrical Building $ 4.2 $ 5.3
Influent Splitter Box $ 1.2 $ 1.5
Secondary Effluent Pump Station $ 1.7 $ 2.1
Plant Drain Pump Station $ 1.7 $ 2.1
Digester Rehab / Solids Holding $ 4.4 $ 5.5
Solids Thickening $ 6.4 $ 8.0
Sludge Drying Bed Rehab $ 3.0 $ 3.8
Total Cost $ 34.5 $43.1
Secondary Treatment Alternatives
Figure 4.10 compares the total project costs for the secondary treatment alternatives, and Table 4.7 presents the breakdown of capital costs for secondary treatment alternatives and common improvements.

Appendix 4A provides a more detailed breakdown of capital costs for the common improvements and secondary treatment technologies.

CHAPTER 4 - ALTERNATIVE ANALYSIS
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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-20
Costs are shown as Total Project Costs.

Figure 4.10 Capital Costs – Secondary Treatment Alternatives Table 4.7 Technology Alternatives Capital Project Costs Element MLE (Million $) MBR (Million $) Ox Ditch (Million $) Bioreactor $ 64.4 $ 34.3 $ 81.1
Secondary Clarifiers $ 33.5 -- $ 34.6
MBR -- $ 58.8 --
Fine Screens -- $ 6.3 --
ML Pump Station / Splitter $ 4.7 $ 2.0 $ 1.6
RAS/WAS Pump Station $ 6.7 -- $ 5.7
Blower Building $ 10.2 $ 13.3 $ 0.6
Secondary Treatment Cost $ 119.6 $ 114.7 $ 123.7
Common Improvements $ 43.1 $ 43.1 $ 43.1
Total Project Cost $ 162.6 $ 157.8 $ 166.8
The secondary treatment alternatives have similar capital project costs, within the level of accuracy of the Class 5 estimate. While the MBR has a much lower cost for the bioreactor earthwork and concrete, the additional equipment costs and fine screen area balances out with the higher bioreactor and clarifier costs for the MLE and ox ditch alternatives. The ox ditch has the highest bioreactor and clarifier capital cost due to the larger footprint, but it doesn’t require the cost for a blower building.

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-21

4.5.2.2 O&M Costs
Table 4.11 compares the annual O&M costs for the secondary treatment alternatives and Table 4.8 presents the breakdown of O&M costs. Appendix 4B provides a more detailed breakdown of annual O&M costs for each secondary treatment alternative.

Figure 4.11 Annual O&M Costs – Secondary Treatment Alternatives Table 4.8 Technology Alternatives O&M Costs
O&M Category MLE (Thousand $) MBR (Thousand $) Ox Ditch (Thousand $) Power $ 1,000 $ 1,920 $ 1,550
Polymer $ 130 $ 105 $ 95
Chemicals -- $ 45 --
Labor $ 380 $ 580 $ 265
Hauling $ 380 $ 320 $ 300
Maintenance $ 710 $ 1030 $ 690
Total $ 2,600 $ 4,000 $ 2,900
MLE has the lowest estimated annual O&M costs, followed closely by ox ditch, with the MBR alternative having much higher O&M costs. Power costs are largely proportional to the aeration and pumping requirements for the process. Ox ditch has higher aeration power because the surface aerators are less efficient at providing oxygen compared to blowers and fine bubble diffusers. MBR has even higher power requirements due to the additional scour blowers and permeate pumps. While chemicals aren’t a significant portion of the O&M costs for the MBR alternative, they are not required for the other alternatives. Labor for the ox ditch is assumed to be the lowest at 14.5 hrs/day, compared to 20.5 hrs/day CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-22
for MLE and 31.5 hrs/day for MBR. Similarly, hauling for the ox ditch is the lowest due to the more stable, lower volume sludge wasted from the process as described in the previous section. The maintenance costs are largely proportional to the capital equipment costs, which consider a typical 20-year replacement, apart from the membranes, which are assumed to be replaced every 10 years.

4.5.2.3 Life Cycle Costs
Figure 4.12 compares the 20-year LCCs for the secondary treatment alternatives, excluding costs associated with common improvements. Table 4.9 provides a breakdown of capital, O&M, and lifecycle costs for the treatment alternatives.

Figure 4.12 Life Cycle Costs – Secondary Treatment Alternatives Table 4.9 Technology Alternatives Lifecycle Costs
O&M Category MLE (Million $) MBR (Million $) Ox Ditch (Million $) Present Value of 20-yr O&M Cost $ 44.9 $ 69.6 $ 50.6
Project Cost $ 119.6 $ 114.7 $ 123.7
Common Improvements $ 43.1 $ 43.1 $ 43.1
LCC (Without Common
Improvements)
$ 164.5 $ 184.2 $ 174.2
LCC (With Common Improvements) $ 207.6 $ 227.3 $ 217.3
MLE has the lowest LCC despite being in between the other alternatives for capital project cost. Its lower power, maintenance, and labor costs contribute to a significantly cheaper 20yr O&M cost. MBR has the highest LCC due to its steeper O&M cost which includes replacing the membranes after 10 years of operation. Despite such rankings, all three alternatives fall within reasonable comparison for the estimate class conducted.

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-23

4.6 Site Visits
Carollo and City staff toured three wastewater treatment plants to get a firsthand look at the technologies evaluated in this DWWTP Facility Plan. At each plant tour, City staff asked the plant staff questions (e.g., O&M requirements, advantages, disadvantages, seasonal operating conditions) for a deeper understanding of the treatment technologies.

On November 7th, Carollo and City staff visited the Visalia WRF to tour the MBR process. Key process units included the membrane tanks, MBR cassettes, fine screens, process and scour blowers, CIP chemical system, and various pump stations.

On November 10th, Carollo and City staff visited the Hanford WWTP and Fresno-Clovis Regional Wastewater Reclamation Facility (RWRF). At the Hanford WWTP, City staff examined the oxidation ditch, circular secondary clarifiers, RAS/WAS pump station, and sludge drying beds. The oxidation ditch at Hanford is similar in size to each of the ox ditches needed for the DWWTP plant expansion. Discussion with Hanford O&M staff included reliability of the treatment process, low O&M requirements, and dependable treatment performance. At the Fresno RWRF, City staff reviewed the plant’s bioreactors similar to the MLE process, aeration blowers, circular primary clarifiers and rectangular secondary clarifiers.

4.7 Recommended Treatment Process
The three treatment alternatives assessed in the detailed evaluation are all proven technologies capable of producing effluents that reliably meet regulatory limits. Based on discussions with the City, there is a preference for the oxidation ditch alternative due to its minimal mechanical equipment, ease of O&M, and ability to attenuate influent variability relative to the other alternatives. The estimated capital project cost for full greenfield buildout including recommended common improvements is around $165M. The City will be working with a rate consultant to understand how the current rates can support anticipated project costs and identify any funding needs. This section describes the implementation of the recommended alternative, including opportunities to reduce project costs and potential phasing.

4.7.1 Opportunities to Reduce Capital Costs
There are several areas where capital costs can be reduced by scaling back scope or leveraging existing assets. The following section outlines these opportunities without affecting the overall treatment capacity.

Reduce Admin Building Scope
Based on discussion with the City, there have been internal preliminary discussions for a future corporation yard across the street from the DWWTP. Early conversations suggested that the new admin building could potentially be located at this site and part of the corp yard project rather than the DWWTP project. However, the decision remains uncertain, and the full scope of the building has not yet been decided by the City. Per request from the City, a high-level budgetary cost for the new admin building was included in the plant expansion total project cost, however, it may fall under a separate City project budget in the future.

The new admin building was assumed to be an architecturally designed building with a footprint 50% larger than the existing admin building and would be equipped with larger laboratory space, offices, conference rooms, lockers, breakroom, and operator workstations. The total project cost for a new CHAPTER 4 - ALTERNATIVE ANALYSIS
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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-24
administrative building was estimated at around $15,000,000 (included in the common improvements total cost estimate). Cost saving measures include considering simpler building style, such as a preengineered structure or trailer units, smaller, right-sized laboratory and workspaces, and unisex locker rooms.

Rehabilitate Biosolids Building
Further analysis by a structural and/or roofing specialist is required to evaluate the feasibility of rehabilitating the existing biosolids building, as noted in Chapter 2. If the assessment confirms that the existing building is suitable for rehab, it could eliminate the need for constructing a new slab and shade canopy for the planned thickening equipment. Rehabilitating the biosolids building would likely also require demolishing the sludge heating units and confirming the viability or replacing the existing GBT.

Salvage Existing Gravity Belt Thickener
Although the existing GBT was installed nearly 30 years ago, it has been offline since 2014, and City staff have indicated it may be able to be put back into service. It is recommended that the GBT is operated for several months to confirm its performance and reliability. If testing proves successful, there could be significant cost savings, as procurement would be reduced to only one new GBT for the proposed thickening process. If the existing GBT is functional, it would still need to be rehabbed with a new vendor control panel. A second unit is recommended regardless, for redundancy, and the existing GBT could be used as backup.

Sludge Holding Lagoon vs. Digester Rehabilitation
Rehabilitating the existing digesters for use as sludge holding tanks requires mixers, diffusers, blowers, and mechanical and structural rehab work. An alternative approach would be to construct an earthen sludge holding lagoon in lieu of sludge holding tanks. A sludge holding lagoon may offer a lower cost alternative to rehabbing the digesters, but it likely would not provide the same level of redundancy as converting the digesters and would require additional footprint on site. The sludge lagoon would include excavation, soil liner, surface aerator, and a sludge transfer pump station. Figure 4.13 below shows a possible layout for this option with the ox ditch.

CHAPTER 4 - ALTERNATIVE ANALYSIS
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-25
Figure 4.13 Sludge Holding Lagoon Layout
Confirm Sludge Drying Bed Rehabilitation Scope
The scope for the sludge drying beds includes full area rehab of the soil-cement liner and replacement of the effluent gates and decant pumps. While any portion of this work may be necessary to keep the sludge drying beds operational, pending confirmation, some or all of it could potentially be deferred. For example, if only half of the sludge drying bed area requires liner repair and all mechanical equipment is replaced, the estimated project cost would decrease by roughly half. This estimate requires further verification through a detailed assessment of the area.

Table 4.10 summarizes the project cost reductions described above.

Table 4.10 Potential Capital Cost Reductions
Reduction Item Potential Project Cost Saving ($M) (1)
Simpler Admin Building $ 5.0
Rehab Biosolids Building $ 2.0
Salvage Existing GBT $ 2.5
Sludge Lagoon $ 3.0
Drying Bed Rehab $ 1.5
TOTAL $ 14.0
Notes:
(1) Reduced project costs are high level estimates that will depend on associated scope of rehab, which has not been estimated and further confirmation that alternative is feasible.

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-26

4.7.2 Split Flow Phased Implementation
Another way to decrease capital costs in the near term is to build treatment capacity for a portion of full buildout flows, sending the remaining flow to the existing treatment process. With the existing flows around 4.5 mgd, constructing half the capacity now (3.5 mgd) and half later, would result in the existing plant treating about 1 mgd in the near term. If the City wishes to pursue a split-flow solution, Carollo recommends construction of one of the two ox ditches sized in section 4.4.4, half of full 2043 buildout capacity, deferring the second to a later time.

It is recommended to provide redundancy for the secondary clarifiers, which would allow a clarifier to be taken offline for maintenance during minimum flow periods while still providing treatment. Phase one would include one ox ditch and two clarifiers and phase two would include a second ox ditch and third clarifier of same size. Preliminary analysis indicates three 105’ clarifiers would be needed at full buildout.

The potential for smaller clarifiers could be evaluated during pre-design for Phase one depending on the specific capacity desired and selected design criteria values.

Constructing only one ox ditch would reduce the scope of the RAS/WAS pump station, deferring procurement of one RAS pump and one WAS pump to the future phase.

Table 4.11 highlights the potential savings from the amendments above. This estimate does not include the cost-saving alternatives as described in section 4.7.1 above.

Table 4.11 Phase One Capital Cost Savings
Reduction Item Reduction Summary Approx Cost Reduction ($M) Ox Ditch Basins Construct one of two ox ditches $ 25
Secondary Clarifiers Construct two smaller clarifiers $ 7 RAS/WAS PS Procure one less RAS & one less WAS pump $ 1 TOTAL $ 33
Since the new plant expansion would not include primary clarification or anaerobic digestion, the domestic plant would not be suited to handle primary sludge. Therefore, the existing primary clarifiers would either need to be abandoned, thereby reducing the capacity of the existing DWWTP, or the primary sludge would need to be pumped to the industrial plant for additional treatment. If the primary clarifiers are abandoned, process modeling estimates the existing plant’s capacity to be reduced to approximately

2.5 mgd. Additional investigation would be needed to determine if the IWWTP can handle additional loads from the DWWTP primary sludge. If so, routing primary sludge to the IWWTP would result in an increase in biogas production.

As mentioned in previous chapters, significant maintenance work is needed on the existing process that cannot currently be performed since there is no redundancy to be able to take units offline. The plant expansion could create opportunities for the City to perform any necessary maintenance, take basins offline, and improve treatment performance and reliability of existing processes.

Figure 4.16 below illustrates the potential range of project costs, including common improvements, comparing the full buildout scenario to the phased implementation with and without the opportunities to reduce capital costs presented in Section 4.7.1. Opportunities to reduce capital costs are also referred to as VE. As mentioned previously, some reductions are contingent on further investigation and/or have associated costs that cannot be represented at this time.

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FEBRUARY 2026 / DRAFT / CAROLLO

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 4-27
Costs are shown as Total Project Costs.

Figure 4.14 Reduced Scope Common Improvements Capital Costs CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2A
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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
APPENDIX 2A CONDITION ASSESSMENT SCORING

RESULTS
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2A
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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2A-1
Table 2A.1 Condition Scoring Guideline
Condition Score General Description Percent Life Consumed 1 (Best) Good: Asset is in good condition (no defects). 0 - 39 2 Acceptable: Asset has minor defects. 40 - 64
3 Fair: Asset has significant defects that will affect reliability or efficiency. 65 - 79 4 Poor: Asset is highly unreliable or inefficient. 80 - 89 5 (Worst) Failed: Asset is no longer able to function in its current condition. 90-100 Table 2A.2 Asset Condition Scoring
Discipline Asset Name General Condition Score Performance Score Mechanical Aeration Blower No. 1 5 5
Mechanical Aeration Blower No. 2 5 5
Mechanical Aeration Blower No. 3 5 5
Mechanical Aeration Blower No. 4 5 5
Mechanical Biofilter Feed Pump No. 1 3 3
Mechanical Biofilter Feed Pump No. 2 3 3
Mechanical Biofilter Feed Pump No. 3 2 2
Mechanical Biofilter Feed Pump No. 4 2 2
Mechanical Digester Sludge Mixing Pump No. 1 3 3
Mechanical Digester Sludge Mixing Pump No. 2 4 5
Mechanical Bar Screen No. 1 2 2
Mechanical Bar Screen No. 2 2 2
Mechanical Booster Pump No. 1 2 2
Mechanical Booster Pump No. 2 2 2
Mechanical Grit Cyclone/Classifier 2 2
Mechanical Grit Pump No. 1 2 2
Mechanical Grit Pump No. 2 2 2
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2A
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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2A-2
Discipline Asset Name General Condition Score Performance Score Mechanical Industrial Plant Bypass Piping 2 2
Mechanical Screening Compactor No. 1 2 2
Mechanical Screening Compactor No. 2 2 2
Mechanical Influent Pump No. 1 2 2
Mechanical Influent Pump No. 2 2 2
Mechanical Influent Pump No. 3 2 2
Mechanical Influent Pump No. 4 2 2
Mechanical IMLR Piping 3 2
Mechanical Primary Scum Pump No. 1 1 1
Mechanical Primary Scum Pump No. 2 1 1
Mechanical Primary Scum Pump No. 3 1 1
Mechanical Primary Sludge Pump No. 1 1 1
Mechanical Primary Sludge Pump No. 2 1 1
Mechanical Primary Sludge Pump No. 3 1 1
Mechanical Primary Sludge Pump No. 4 1 1
Mechanical Pump Gallery Ventilation Blower 1 1
Mechanical RAS Piping 3 2
Mechanical RAS Pump No. 1 1 1
Mechanical RAS Pump No. 2 1 1
Mechanical RAS Pump No. 3 1 1
Mechanical RAS Pump No. 4 1 1
Mechanical RAS Pump No. 5 1 1
Mechanical RAS Pump No. 6 1 1
Mechanical Secondary Effluent Pump No. 1 5 5
Mechanical Secondary Effluent Pump No. 2 4 3
Mechanical Secondary Effluent Pump No. 3 4 3
Mechanical Secondary Effluent Pump No. 4 4 3
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2A
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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2A-3
Discipline Asset Name General Condition Score Performance Score Mechanical Secondary Influent Piping 2 2
Mechanical Polymer Feed Pump 2 2
Mechanical TWAS Pump 3 N/A
Mechanical WAS Piping 3 2
Mechanical WAS Pump No.1 1 1
Mechanical WAS Pump No. 2 1 1
Structural Aeration Basin No. 1 2 2
Structural Aeration Basin No. 2 2 2
Structural Aeration Basin No. 3 2 2
Structural Anoxic Basin 2 2
Structural Biofilters N/A N/A
Structural Biofilter Recirculation Wet Well 2 2
Structural Commingled Effluent Mixing Box 1 1
Structural Digester No. 1 3 3
Structural Digester No. 2 3 3
Structural Electrical Room 6 (Building) 1 1
Structural Grit Influent Channel 1 1
Structural Grit Removal Tank 1 1
Structural Main Control Building 3 3
Structural Primary Sedimentation Basin No. 1 2 2
Structural Primary Sedimentation Basin No. 2 2 2
Structural Primary Sedimentation Basin No. 3 2 2
Structural Primary Sedimentation Basin No. 4 2 2
Structural Secondary Effluent Pump Station 3 3
Structural Secondary Sedimentation Basin No. 1 2 2
Structural Secondary Sedimentation Basin No. 2 2 2
Structural Secondary Sedimentation Basin No. 3 2 2
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2A
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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2A-4
Discipline Asset Name General Condition Score Performance Score Structural Secondary Sedimentation Basin No. 4 2 2
Structural Secondary Sedimentation Basin No. 5 2 2
Structural Secondary Sedimentation Basin No. 6 2 2
Structural Biosolids Building 2 2
Structural Blower Building 3 3
Structural Sludge Drying Beds N/A N/A
Structural Gravity Belt Thickener 3 N/A
Electrical Control Room - SWBD-PG (Rating: 2000A, 480V, 3 phase, 65 kA) 3 3 Electrical Control Room - Main switchboard 3 3
Electrical Control Room - MCC-P1 3 3
Electrical Control Room - SSRVw1,2,3,4 3 3
Electrical Control Room - 615 kW Generator 3 3
Electrical Control Room - Automatic Transfer Switch for 615 kW generator 3 3 Electrical Control Room - MCC-6 3 3
Electrical Control Room - TR3L (25 kVA transformer) 3 3 Electrical Control Room - Power panel P3 3 3
Electrical Control Room - Lighting panel 3L 3 3
Electrical ER 6 - SWBD-1 2 2
Electrical ER 6 - Influent pump VFDs 2 2
Electrical ER 6 - MCC-2 2 2
Electrical ER 6 - 30 kVA transformer 1 2 2
Electrical ER 6 - 30 kVA transformer 2 2 2
Electrical ER 6 - 2000 kW generator 2 2
Electrical ER 6 - Automatic transfer switch for 2000 kW generator 2 2 Notes:

A - ampere; ER - electrical room; IMLR - internal mixed liquor return; kA - kiloamperes; kVA - kilovolt-ampere; kW - kilowatt; MCC - motor control center; N/A - not applicable; No. - number; RAS - return activated sludge; SSRV - solid state reduced voltage starter; SWBD - switchboard; TWAS - thickened waste activated sludge; V - volt; VFD - variable frequency drive; WAS - waste activated sludge.

CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2B
FEBRUARY 2026 / DRAFT / CAROLLO

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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
APPENDIX 2B CONDITION ASSESSMENT PHOTOS
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2B
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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2B-1
Figure 2B.1 DWWTP Influent Headworks
Figure 2B.2 Influent Pump Station
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2B
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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2B-2
Figure 2B.3 Influent Pump Station
Figure 2B.4 Primary Sedimentation Basin
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2B
SEPTEMBER 2025 / DRAFT / CAROLLO

CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2B-3
Figure 2B.5 Primary Sedimentation Basin Drive Mechanism Figure 2B.6 Aeration Basin
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2B
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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2B-4
Figure 2B.7 Aeration Blowers in Blower Building
Figure 2B.8 Secondary Sedimentation Basins
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2B
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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2B-5
Figure 2B.9 Secondary Effluent Pump Station (L) and Secondary Effluent Pump No. 4 Corrosion (R) Figure 2B.10 Combined Effluent Box
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2B
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DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2B-6
Figure 2B.11 Non-Operational Sludge Heating Unit
Figure 2B.12 Gravity Belt Thickener
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2B
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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2B-7
Figure 2B.13 Anaerobic Digester
Figure 2B.14 Sludge Drying Beds
CHAPTER 2 – CONDITION ASSESSMENT RESULTS / APPENDIX 2B
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CITY OF TULARE
DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN 2B-8
Figure 2B.15 Electrical Equipment in Admin Building
Figure 2B.16 Generator in Admin Building
CHAPTER 3 – EXISTING PLANT EVALUATION/APPENDIX 3A
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CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
APPENDIX 3A SPECIAL SAMPLING PLAN
Summary of Daily Composite and Grab Wastewater Sampling City of Tulare Domestic Wastewater Treatment Plant Facilities Plan

1. Screened
Influent

2. Primary
Sedimentation
Basin Effluent

3. Aeration Basin
Influent

4. Secondary
Effluent 5. Primary Sludge

6. Waste Activated
Sludge
Field Measurements [b]
Temperature SM 2550 B ● ●pH ● ● ● ●
Unfiltered
COD SM 5220 B, C, or D [e] ● ●BOD SM 5210 B ● ●TSS SM 2540 D ● ● ● ● ●VSS SM 2540 E ● ● ● ● ●TS SM 2540 G ●VS SM 2540 G ●TKN SM 4500-Norg B or C ● ●TP SM 4500-PE ● ●OP SM 4500-PE ● ● ●VFA SM 5560 D ●Alkalinity SM 2320 B ● ● ● Filtered [f]
sCOD SM 5220 B, C, or D [e] ● ● ●sBOD SM 5210 B ● ● ●sTKN SM 4500-Norg B or C ● ● Filtered [g]
NH3 SM 4500-NH3 C ● ● ●NO2 SM 4500-NO3 E [h] ●TON SM 4500-NO3 E ● ● Notes:[a] - Sampling included herein that is currently conducted by the City should be considered part of execution of this plan. [b] - On-line temperature and pH meters will be used where available. Otherwise, temperature and pH will be measured on grab samples obtained when the composite or grab sample is collected. [c] - Composite sampling will be flow-paced where possible and time-weighted elsewhere. Time-weighted samplers will be programmed with a non-uniform, time-weighted frequency to simulate the approximate flow characteristics. [d] - Listed references are "Standard Methods for the Examination of Water and Wastewater, 21st edition". [e] - HACH8000 is acceptable for COD using ranges 3-150 mg/L and 20-1500 mg/L. [f] - Filtered through 1.2 - 1.5 micron glass fiber filter (the same as those typically used to measure plant TSS/VSS). Filtration should occur immediately after collection before samples are shipped [g] - Filtered through 0.45 micron Millipore filter. Filtration should occur immediately after collection before samples are shipped to an outside lab. Prior to filtration, filters should be triple rinsed with DI water. [h] - HACH8507 is acceptable for nitrite analysis. COD - chemical oxygen demand BOD - five-day biochemical oxygen demand TSS - total suspended solids VSS - volatile suspended solids TS - total solids VS - volatile solids TKN - total Kjeldahl nitrogen TP - total phosphorusOP - orthophosphateVFA - volatile fatty acidssoluble CODsoluble BODsoluble TKNNH3 - ammonia nitrogen NO2 - nitrite nitrogen TON - total oxidized nitrogen (nitrite & nitrate nitrogen) Sample [a] Analytical Method [d]
Composite Sample [b] [c] Composite Samples Preferred Grab Samples Acceptable (1x/day) 1 2
3 4
5 6
CHAPTER 3 – EXISTING PLANT EVALUATION/APPENDIX 3B
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
APPENDIX 3B OPERATIONAL DATA AND PERFORMANCE
GRAPHS
Figure 3B.1 Influent and Primary Effluent TSS Concentrations Figure 3B.2 Primary Treatment TSS Removal
Figure 3B.3 Primary Sludge Flow
Figure 3B.4 Secondary Influent Flow (PE + RAS + MLR)
Figure 3B.5 Mixed Liquor Concentration
Figure 3B.6 Sludge Volume Index
Figure 3B.7 Anoxic Basin Aerated Dissolved Oxygen
Figure 3B.8 Aeration Basin Dissolved Oxygen
Figure 3B.9 Airflow
Figure 3B.10 Total and aerobic SRT
Figure 3B.11 WAS Loads
Figure 3B.12 WAS Flow
Figure 3B.13 Alkalinity
Figure 3B.14 Effluent TSS Compliance
Figure 3B.15 Effluent BOD Compliance
Figure 3B.16 Effluent Total Nitrogen Compliance
CHAPTER 4 - ALTERNATIVE ANALYSIS/APPENDDIX 4A
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
APPENDIX 4A CAPITAL COST
CHAPTER 4 - ALTERNATIVE ANALYSIS/APPENDDIX 4A
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
CHAPTER 4 - ALTERNATIVE ANALYSIS/APPENDDIX 4A
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
HAPTER 4 - ALTERNATIVE ANALYSIS/APPENDDIX 4A
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
HAPTER 4 - ALTERNATIVE ANALYSIS/APPENDDIX 4A
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
CHAPTER 4 - ALTERNATIVE ANALYSIS/APPENDIX 4B
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
APPENDIX 4B O&M COSTS
CHAPTER 4 - ALTERNATIVE ANALYSIS/APPENDIX 4B
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
CHAPTER 4 - ALTERNATIVE ANALYSIS/APPENDIX 4B
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
CHAPTER 4 - ALTERNATIVE ANALYSIS/APPENDIX 4B
FEBRUARY 2026 / DRAFT / CAROLLO

CITY OF TULARE

DOMESTIC WASTEWATER TREATMENT PLANT FACILITY PLAN
Staff Report
Meeting: City Council
Date: March 3, 2026
Department: Community Services
Submitted by: Chris Orr – Community Services Director
Agenda Title: Funding for the 250th Anniversary Independence Day Event at Zumwalt Park

RECOMMENDED ACTION
Approve a subsidy of $40,000 from the General Fund unassigned fund balance account to subsidize the July 4th 250th Anniversary Independence Day Event at Zumwalt Park Featuring the Sequoia Symphony Orchestra.

SUMMARY
At the February 17, 2026, City Council meeting, the City Council requested a breakdown for the City’s estimated costs, and potential revenues for the Sequoia Symphony to perform at the Adventist Health Amphitheater on July 4, 2026. The estimated costs and potential revenues follow:

Estimated Costs
Production $ (22,500.00)
Symphony $ (15,000.00)
Janitorial $ (1,500.00)
Security $ (1,000.00)
$ (40,000.00)
Potential Revenue
Source Cost ea. Qty Total
VIP boxes $ 500.00 18 $ 9,000.00
VIP seats $ 25.00 200 $ 5,000.00
$ 14,000.00
Any bar revenue will be used to cover costs assumed by Spade Entertainment such as catering, hotel, etc. Spade Entertainment will not be charging a fee for their services for this event. The cost for marketing is estimated to be $2,500 and is already included in Spade Entertainment’s budget.

FISCAL IMPACT & FUNDING SOURCES
Reduction in the General Fund unassigned fund balance account.

ENVIRONMENTAL REVIEW
This action does not constitute a “project” pursuant to the California Environmental Quality Act (CEQA)

POTENTIAL CONFLICT OF INTEREST
Staff is not aware of any conflicts of interest

LEGAL REVIEW
This item does not require legal review.

Item #: 9.3
General Business

PUBLIC NOTICE
This item does not require a public hearing and was noticed as a part of the agenda.

ALTERNATIVE ACTION

1. Approve with changes

2. Deny

3. Table

ATTACHMENTS
None
Reviewed/Approved:

Staff Report
Meeting: City Council
Date: March 3, 2026
Department: Finance
Submitted by: Mark Roberts, Chief Financial Officer
Agenda Title: Fiscal Year 2026 General Fund Mid-Year Budget Review

RECOMMENDED ACTION
Receive a presentation and adopt a resolution approving Fiscal Year 2026 Budget supplemental appropriation requests.

SUMMARY
This report provides the mid-year status of the combined operating and capital budgets of General Fund, the City’s primary operating fund. The purpose of this report is to review the financial activities of the first half of the current fiscal year, provide projections of revenues and expenditures through the end of the fiscal year, and recommend various budget adjustments.

Revenues
As shown in Table 1 below, fiscal year 2026 General Fund revenues are estimated to be within 1% of budget. This variance of approximately $599,000 is largely attributed to less-than-projected revenues in utility users’ tax, franchise taxes, cannabis/dispensary tax, and other revenues.

Table 2 compares General Fund revenues as of December 31st for the current and prior fiscal years.

During the first six months of fiscal year 2026, total revenues were approximately $29.7 million, which is $1.3 million more than the $28.4 million in revenues received during the first half of fiscal year 2025. The primary drivers of this increase were higher revenues from transactions and use tax, property taxes, and sales and use tax.

Table 1: Fiscal Year-End Revenue Projections

GENERAL FUND

REVENUES
FISCAL YEAR 2026
Revenue Category 1
Projected
Actual
Adjusted
Budget 2
Projected
Balance
%
Variance
Sales & Use Tax $ 15,000,000 $ 14,000,000 $ 1,000,000 7.1% Transactions & Use Tax (Meas. I) 8,350,000 8,300,000 50,000 0.6% Property Taxes 9,473,000 8,993,000 480,000 5.3%
Utility Users Tax 10,750,000 12,200,000 (1,450,000) -11.9% Property Tax in Lieu of VLF 8,500,000 8,500,000 - 0.0%
Transient Occupancy Tax 2,250,000 2,250,000 - 0.0%
Item #: 9.4
General Business
Cannabis/Dispensary Tax (Meas. Y) 900,000 1,000,000 (100,000) -10.0% Franchise Taxes 1,600,000 1,790,000 (190,000) -10.6%
Other Revenues 15,848,465 16,236,989 (388,524) -2.4%
Total $ 72,671,475 $ 73,269,989 ($ 598,524) -0.8%
1 Transfer(s) in not included.
2 Adopted budget total, plus budget amendments, encumbrances, & capital projects appropriations carried forward from previous fiscal year(s)
Table 2: Mid-Year Revenue Comparison

GENERAL FUND

REVENUES
AS OF DECEMBER 31ST
Revenue Category 1 FY 26 FY 25 Difference
Sales & Use Tax $ 5,119,273 $ 4,822,746 $ 296,527
Transactions & Use Tax (Meas. I) 2,755,580 2,087,872 667,708 Property Taxes 5,045,744 4,633,658 412,086
Utility Users Tax 2 5,207,024 5,556,481 (349,458)
Property Tax in Lieu of VLF 3 4,309,961 4,001,706 (308,255) Transient Occupancy Tax 746,628 1,079,732 (333,105)
Cannabis/Dispensary Tax (Meas. Y) 203,486 218,196 (14,709) Franchise Taxes 113,098 65,606 47,493
Other Revenues 6,244,345 5,929,947 314,339
Total $ 29,745,139 $ 28,395,943 $ 1,349,195
1 Transfer(s) in not included. 3
VLF – vehicle license fees
Expenditures
As reflected in Table 3, General Fund expenditures at year-end are expected to be $2.2 million less than budgeted. This variance is primarily due to vacant positions City-wide. Police and Fire Department vacancies represent the most significant number of vacant positions and resulting cost savings, with ten Police positions and six Firefighter/Paramedic positions vacant for most of the first half of fiscal year 2026. The approximate total cost savings of these sixteen positions is $1.9 million.

Table 3: Fiscal Year-End Expenditure Projections

GENERAL FUND

EXPENDITURES
FISCAL YEAR 2026
Expenditure Category
Projected
Actual
Adjusted
Budget 1
Projected
Balance
%
Variance
Salaries & Benefits $ 41,566,324 $ 43,477,231 ($ 1,910,907) -4.4% Maintenance & Operations 14,675,038 14,991,995 (316,957) -2.1% Internal Service Charges & Alloc. Costs 11,443,608 11,443,608 - 0.0% Capital Outlay 862,937 862,937 - 0.0%
Debt Service 491,040 491,040 - 0.0%
Capital Improvements - - - 0.0%
Total $ 69,038,947 $ 71,266,811 ($ 2,227,864) -3.1%
1 Adopted budget total, plus budget amendments, encumbrances, & capital projects appropriations carried forward from previous fiscal year(s)
Table 4: Mid-Year Expenditure Comparison

GENERAL FUND

Net Impact on Unassigned Fund Balance
As seen in Table 1 above, the General Fund is expected to realize slightly less revenue than budgeted.

And Table 3 shows General Fund expenditures are expected to end the year at $2.2 million under budget.

Combining current revenue and expenditure projections, along with planned transfers, results in a $1.2 million anticipated use of fund balance. This projection represents an improvement in the anticipated use of fund balance of $1.6 million, compared to the adjusted budget.

GENERAL FUND

Supplemental Appropriation Requests
During the mid-year budget review process, Department of Finance staff worked with departments to determine supplemental appropriations (i.e., budget adjustments) needed, based upon expenses not anticipated during the annual budgeting process, one-time priorities, and new initiatives. These are detailed in Exhibit A, which accompanies this staff report. For the General Fund, these supplemental appropriations represent a use of up to $1,181,659 in fund balance, which is not included in the forecasts presented above.

Staff will continue to monitor expenses and provide revised projections where needed.

FISCAL IMPACT & FUNDING SOURCES
See attached Exhibit A for detail of recommended and requested budget adjustments and totals by fund.

ENVIRONMENTAL REVIEW
This action does not constitute a “project” pursuant to the California Environmental Quality Act (CEQA).

POTENTIAL CONFLICT OF INTEREST
Staff is not aware of any conflicts of interest.

LEGAL REVIEW
This item does not require legal review.

PUBLIC NOTICE
This item does not require a public hearing and was noticed as a part of the agenda.

ALTERNATIVE ACTION

1. Approve with changes

2. Deny

3. Table
Adopting the proposed mid-year adjustments will authorize expenditures deemed necessary by staff to effectively carry out its responsibilities. If City Council does not approve the proposed changes, the budget may be exceeded, and/or staff may be unable to perform their work as effectively as possible.

ATTACHMENTS

1. Resolution

2. Exhibit A - Recommended Mid-Year Budget Adjustments Fiscal Year 2026 Reviewed/Approved:

RESOLUTION 2026-XXX

A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF TULARE
AMENDING THE FISCAL YEAR 2026 BUDGET
WHEREAS, on June 17, 2025, the City Council adopted the City of Tulare’s Fiscal Year 2026 Adopted Budget following a public hearing; and
WHEREAS, as part of the mid-year budget review process, the Department of Finance reviewed actual revenues and expenditures for the first six months of the fiscal year and projected the same through the remainder of the fiscal year; and
WHEREAS, on March 03, 2026, City staff delivered a mid-year budget review to Council, which included a request to amend the budget for Council’s review and consideration; and WHEREAS, in accordance with Administrative Policy CM-10 Budget Policies and Practices, the City Council may amend or supplement the budget any time after its adoption; and WHEREAS, City staff has proposed specific amendments to the Budget.

NOW, THEREFORE, BE IT RESOLVED by the City Council of the City of Tulare, as follows:

Section 1. The City Council authorizes the amendments to the Fiscal Year 2026 Budget up to the amounts presented in Exhibit A.

PASSED, APPROVED, AND ADOPTED by the City Council of the City of Tulare this 3rd day of March 2026, by the following vote:

Ayes:

Noes:

Absent:

Abstain:

Patrick Isherwood, President of the Council
and Ex-Officio Mayor
ATTEST:

Marc Mondell, City Clerk
By Melissa Wilcox, Chief Deputy City Clerk
The presence of an electronic signature certifies that the foregoing is a true and correct copy as approved by the Tulare City Council.

Exhibit A
Fund Department Expenditure Account
Appropn/Trfr
Amount Revenue Account if Applicable
Rev./Trfr
Amount
Net Use of
Fund Balance
General Fund (100)
1 Police Maintenance & Operations $132,000 $132,000
33,000 39,000 60,000
1 Fire Maintenance & Operations $132,000 $132,000
50,000 65,000 17,000
1 Community Services Salaries & Benefits $22,800 $22,800 22,800
2 Community Services Maintenance & Operations $87,200 $87,200 48,180 15,000 24,020

RECOMMENDED MID-YEAR BUDGET ADJUSTMENTS
Fiscal Year 2026
Other Contractual Services (100-200-201-000-000-5220) To increase the appropriation for Lexipol reporting add-on services.Other Contractual Services (100-200-200-202-000-5220) To increase the appropriation for additional security fencing to secure the Fire Station 62 parking lot.Repair & Maintenance - Firefighting Apparatus (100-200-200-202-000-5285) To increase the appropriation for additional fire apparatus maintenance.Temporary Part-Time Staff (100-310-301-306-310-5103) To increase the appropriation for additional Zumwalt Park seasonal staffing.Communication Equipment (100-200-201-000-000-5602) To increase the appropriation for new radios.Tactical Equipment (100-200-201-206-210-5627) To increase the appropriation for the purchase of night vision equipment.Medical Supplies (100-200-200-202-000-5332) To increase the appropriation for additional medical IO and drill equipment.Other Contractual Services (100-310-301-306-310-5220) To increase the appropriation for an increase in park edging services.Venue Operations (100-310-301-306-310-5213) To increase the appropriation for Zumwalt Park splash pad monthly maintenance.Repair & Maintenance - Concrete & Asphalt (100-310-301-306-310-5290) To increase the appropriation for an emergency concrete repair & replacement at Del Lago Park. 1 of 6
Exhibit A
Fund Department Expenditure Account
Appropn/Trfr
Amount Revenue Account if Applicable
Rev./Trfr
Amount
Net Use of
Fund Balance

RECOMMENDED MID-YEAR BUDGET ADJUSTMENTS
Fiscal Year 2026
1 General Services Salaries & Benefits $60,000 $60,000
60,000
2 General Services Maintenance & Operations $20,000 $20,000 20,000
1 City Wide Internal Service Charges - GF $137,659 $137,659 137,659
1 Non-Departmental Maintenance & Operations $590,000 $590,000 550,000
40,000
General Fund - Unassigned Fund Balance $1,181,659 $1,181,659 General Fund Total $1,181,659 $1,181,659
Outside Labor - Temporary Relief (100-330-303-318-000-5198) To increase the appropriation for a replacement temp position whose hours are complete, to maintain graffiti and illegal dumping services.Weed Abatement / Lot Clearing (100-200-303-317-345-5215) To increase the appropriation for additional property clean-ups.Zumwalt Park Amphitheater Operations (100-100-500-000-000-5217) To increase the appropriation for the previously approved Spade Entertainment contract by the City Council at the December 16th, 2026 Council Meeting. Zumwalt Park Amphitheater Operations (100-100-500-000-000-5217) To increase the appropriation for the 4th of July event.Building Service Charges (5756) To increase building service internal service charges to offset the Facilities Maintenance Fund appropriation increase. 2 of 6
Exhibit A
Fund Department Expenditure Account
Appropn/Trfr
Amount Revenue Account if Applicable
Rev./Trfr
Amount
Net Use of
Fund Balance

RECOMMENDED MID-YEAR BUDGET ADJUSTMENTS
Fiscal Year 2026
Facilities Maintenance Fund (604)
1 Facilities Maintenance Salaries & Benefits $60,000 $60,000 $0 60,000 Increase in General Fund Internal
Service Charges (5756)
60,000
2 Facilities Maintenance Maintenance & Operations $90,000 $90,000 $0 20,000 Increase in General Fund Internal
Service Charges (5756)
20,000
40,000 Increase in General Fund Internal
Service Charges (5756)
40,000
30,000 Increase in General Fund Internal
Service Charges (5756) & General Fund departmental adjustments 30,000
3 Facilities Maintenance Capital Outlay $50,000 $50,000 $0 50,000 General Fund departmental
adjustments
50,000
Facilities Maintenance Fund Total $200,000 $200,000 $0Fleet Replacement Fund (605) 1 Police Capital Outlay $20,000 $20,000
20,000
Fleet Replacement Fund Total $20,000 $20,000Outside Labor - Temporary Relief (604-100-303-319-357-5198) To increase the appropriation for a replacement temp position whose hours are complete to continue providing adequate city services. Other Contractual Services (604-100-303-319-357-5220) To increase the appropriation for additional contractual services. Other Professional & Technical Services (604-100-303-319-357-5225) To increase the appropriation for additional professional and technical services.Computer Equipment (604-100-303-319-357-5603) To increase the appropriation to purchase surveillance equipment to monitor the downtown area.Materials & Supplies (604-100-303-319-357-5399) To increase the appropriation for additional material and supplies.Automotive Equipment (605-100-304-325-371-5636) To increase the appropriation for the purchase of a trailer for Police Department operations. 3 of 6
Exhibit A
Fund Department Expenditure Account
Appropn/Trfr
Amount Revenue Account if Applicable
Rev./Trfr
Amount
Net Use of
Fund Balance

RECOMMENDED MID-YEAR BUDGET ADJUSTMENTS
Fiscal Year 2026
Solid Waste & Street Sweeping Fund (105) (INFORMATIONAL. APPROVED BY BPU ON 02-19-2026.) 1 Solid Waste, Residential Maintenance & Operations $60,000 $60,000 60,000
2 Solid Waste, Roll-Off Maintenance & Operations $25,000 $25,000 25,000
Solid Waste & Street Sweeping Fund Total $85,000 $85,000Wastewater Fund (106) (INFORMATIONAL. APPROVED BY BPU ON 02-19-2026.) 1 Sewer System Maintenance & Operations $50,000 $50,000 50,000
2 Domestic Maintenance & Operations $400,000 $400,000
400,000
3 Industrial Maintenance & Operations $400,000 $400,000 400,000
Wastewater Fund Total $850,000 $850,000Utilities, Electricity and Gas (106-530-304-329-393-5233) To account for higher-than-anticipated utility costs.Software Maintenance, Non-SBITA (105-520-304-326-376-5242) To account for higher-than-anticipated software costsSoftware Maintenance, Non-SBITA (105-520-304-326-377-5242) To account for higher-than-anticipated software costsUtilities, Electricity and Gas (106-530-304-329-390-5233) To account for higher-than-anticipated utility costs.Utilities, Electricity and Gas (106-530-304-329-391-5233) To account for higher-than-anticipated utility costs. 4 of 6
Exhibit A
Fund Department Expenditure Account
Appropn/Trfr
Amount Revenue Account if Applicable
Rev./Trfr
Amount
Net Use of
Fund Balance

RECOMMENDED MID-YEAR BUDGET ADJUSTMENTS
Fiscal Year 2026
Water Fund (107) (INFORMATIONAL. APPROVED BY BPU ON 02-19-2026.) 1 Administration/Sales/Collections Maintenance & Operations $40,000 $40,000 40,000
2 Distribution Maintenance & Operations $40,000 $40,000 40,000
3 Extraction Maintenance & Operations $40,000 $40,000
40,000
Water Fund Total $120,000 $120,000Postage (107-540-304-330-395-5240) To account for higher-than-anticipated postage expenditures.Water Pipe, Valves, & Fittings (107-540-304-330-396-5343) To account for higher-than-anticipated expenditures.Other Professional & Technical Services (107-540-304-330-397-5225) To account for higher-than-anticipated expenditures. 5 of 6

COUNCIL ITEM REQUEST FORM
The Council Item Request Form is for members of the City Council to submit written requests to the City Clerk’s Office for inclusion of an item on a future City Council meeting agenda. At the meeting where the initial written request is heard, discussion shall be limited to whether the item should be added to an agenda and a date, not the merit of the item. A majority vote of the City Council is required for the item to be added to a future Council meeting agenda for action. No more than 10 items may be submitted collectively for consideration by all councilmembers at any regular meeting of the Council, and in that regard, no individual councilmember may submit more than three items for consideration at any regular meeting of the Council. In the event more than 10 items are submitted collectively, no more than two items shall be accepted for consideration from any one councilmember.

NAME OF REQUESTING COUNCILMEMBER TODAY’S DATE AGENDA DATE

ITEM TITLE

BRIEF DESCRIPTION/BACKGROUND INFORMATION OF ITEM
Item #: 10.1
Future Agenda Item
Patrick Isherwood, District 5 2/20/2026 3/3/2026
A Tulare Teens on Board with Youth Commission
Request for item to be placed on future Council meeting. Objective is to receive a presentation on updated Teens On Board program and structure for a Youth Commission.

The update includes key information on what the program involves, partners involved, how it would be administrated, who could participate, and when it would take place including a specific timeline. The agenda item would be a presentation and also a request for direction.

Tulare City CouncilMarch 3, 2026

Tulare City Council
March 3, 2026