To: Contra Costa County Flood Control and Water Conservation District
From: Warren Lai, Public Works Director/Chief Engineer
Report Title: Adoption and levy of annual Drainage Area Benefit Assessment in Drainage Area 910 for Fiscal Year 2024-2025. Project No. 7505-6F8167
☒Recommendation of the County Administrator ☐ Recommendation of Board Committee
RECOMMENDATIONS:
ADOPT Resolution adopting and levying the annual Drainage Area Benefit Assessment (DABA) in Drainage Area 910 (DA 910) for Fiscal Year 2024-2025, Danville area.
FISCAL IMPACT:
Adoption and levy of annual Drainage Area Benefit Assessment in Drainage Area 910 for Fiscal Year 2024-2025. Project No. 7505-6F8167
BACKGROUND:
A DABA is a subset of parcels within a defined boundary of a larger drainage area that is assessed to fund flood control infrastructure maintenance that directly benefits the area. Assessments are used to pay for flood control maintenance activities, including complaint investigation, facility inspections, ditch and basin cleaning, maintaining right-of-way access, and additional general or routine drainage maintenance activities. The assessments collected are used only for the maintenance and operation of the flood control facilities within the Contra Costa County Flood Control and Water Conservation District right-of-way limits.
DABAs are established when a development is determined to increase stormwater runoff, inundating existing drainage infrastructure. DABAs are established by agreement with developers or vote by parcel owners. DA 910 was established January 23, 1990, by adoption of Resolution No. 90/54. DA 910 has been assigned a specific number of Impervious Area Units (IAUs), where a single IAU is equal to 1,000 square feet of impervious surface. Parcels within DA 910 are assigned a specific number of IAUs based upon their proportional share of impervious area in accordance with the Benefit Assessment Act of 1982. DA 910 has a total of 686 IAUs, where the typical single-family home may pay an assessment amount of $110.45 for Fiscal Year 2024-2025.
To calculate the assessment, the cost of flood control infrastructure maintenance within DA 910 is budgeted. The cost of flood control infrastructure maintenance varies from year-to-year based upon the planned annual costs and unforeseen maintenance needs. The assessment rate/IAU is the quotient of the budgeted maintenance divided by the number of IAUs assigned to DA 910. The assessment for each parcel is the product of the rate/IAU multiplied by the number of IAUs assigned to the parcel. At the onset of the initial formation, a maximum assessment rate was adopted for the establishment of a reserve fund based on unforeseen costs due to natural disasters or severe weather events. With the establishment of the reserve fund, the initial assessment rate is adjusted annually to account for inflation using the California Construction Cost Index, as cited in the DA’s Engineer’s Report upon formation.
Based on the assessment calculations, where DA 910 has 686 IAUs and budgeted maintenance of $44,450, the assessment rate for Fiscal Year 2024-2025 is calculated to be $64.76. Unspent assessments from Fiscal Year 2024-2025 shall be carried over to Fiscal Year 2024-2025. As a result, the assessment rate that shall be levied will be less than the calculated rate of $64.76.
CONSEQUENCE OF NEGATIVE ACTION:
If the proposed assessment for DA 910 is not adopted, the proposed assessment will not be levied, and the maintenance of the flood control facilities may not happen.
cc: Dorothy Lim, County Auditor-Controller’s Office, dorothy.lim@ac.cccounty.us
THE BOARD OF SUPERVISORS OF CONTRA COSTA COUNTY, CALIFORNIA
and for Special Districts, Agencies and Authorities Governed by the Board
IN THE MATTER OF ADOPTING AND LEVYING ASSESSMENTS IN DRAINAGE AREA 910 FOR FISCAL YEAR 2024-2025.
WHEREAS the Board of Supervisors FINDS that:
1. On January 23, 1990, the Board of Supervisors, as the governing body of the Contra Costa County Flood Control and Water Conservation District (Flood Control District), adopted Resolution No. 90/54, establishing Drainage Area 910 (DA 910) and imposing assessments on parcels within the area of benefit pursuant to the Benefit Assessments Act of 1982 (Gov. Code, §54703 et. seq.), following approval by landowners, for the purpose of funding flood control facility maintenance, such as complaint investigation, facility inspections, ditch and basin cleaning, maintaining right-of-way access, and additional general or routine drainage maintenance activities.
2. Under Resolution No. 90/54, assessments were imposed based upon the annual budgeted cost of flood control facility maintenance for DA 910, the total impervious surface area (described as Impervious Area Units [IAUs], where a single IAU is equal to 1,000 square feet of impervious surface area) assigned to DA 910, and the number of IAUs attributable to each parcel. In this way, assessment amounts were determined on the basis of proportionate stormwater runoff from each parcel, in accordance with Government Code section 54711.
3. Under Resolution No. 90/54, and as approved by landowners of DA 910, (a) the annual assessment rate is the quotient of the annual budgeted maintenance cost divided by the number of IAUs assigned to DA 910; (b) the maximum assessment amount was $88.23/IAU; and (c) the maximum assessment shall be adjusted for annually to account for inflation in accordance with the appropriate construction cost index, cited in the Engineer’s Report.
4. As set forth in Exhibit A, attached hereto and incorporated by this reference, the adjusted maximum assessment rate for Fiscal Year 2023-2024 was $288.45/IAU. The change in the construction cost index from December-to-December is 11.2 percent. Pursuant to Resolution No. 90/54, the maximum assessment rate is adjusted upward by 11.2 percent to $320.76/IAU for Fiscal Year 2024-2025.
5. As set forth in Exhibit A, for Fiscal Year 2024-2025, the budgeted maintenance to be funded by DA 910 assessments is $44,450. Anticipated maintenance activities include facility inspections, ditch cleaning, fence repair, and landscape maintenance, among others.
6. Based on the formula set forth in Resolution No. 90/54, the current number of IAUs in DA 910 (686), and budgeted maintenance of $44,450, the adjusted annual assessment rate for Fiscal Year 2024-2025 would be $64.76/IAU.
7. The annual assessment rate of $64.76 is less than the adjusted maximum rate of $320.76. The annual assessment rate for Fiscal Year 2023-2024 may, therefore, be set at $64.76/IAU.
8. Unspent assessments from Fiscal Year 2023-2024 shall be carried over to Fiscal Year 2024-2025. As a result, the annual assessment rate that shall be levied will be less than the adjusted annual assessment rate of $64.76.
NOW, THEREFORE, the Board hereby determines and resolves that:
1. The annual budgeted cost of flood control facility maintenance to be financed by DA 910 assessments for Fiscal Year 2024-2025 shall not exceed $44,450.
2. Annual assessments shall be levied in DA 910 for Fiscal Year 2023-2024 at a rate of $35.29/IAU, in the specific amounts shown per parcel on Exhibit B, attached hereto and incorporated herein by this reference.
3. The Drainage Area Benefit Assessment shall be collected in the same manner, and subject to the same penalties and priority of lien as other charges and taxes fixed and collected by, or on behalf of, the Flood Control District, pursuant to Government Code section 54718.