TO: Mayor and Members of City Council
THRU: Kristoff Bauer, ICMA-CM, Deputy City Manager
FROM: Sheila Thomas-Ambat, PE, Public Services Director
DATE: January 14, 2020
RE:
Title
Stormwater Master Plan Update
end
COUNCIL DISTRICT(S):
Council District(s)
All
b
Relationship To Strategic Plan:
Goal 3: High Quality Built Environment
Goal 4: Desirable Place to Live, Work and Recreate
Executive Summary:
City Council directed staff to accelerate the City’s stormwater capital improvement program by completing a stormwater masterplan for the entire City within five years. To support this effort, Council voted to increase the stormwater fee as part of the Fiscal Year 2019 budget. City staff selected the firm Freese & Nichols to serve as program manager for the project. The project began in Spring 2019 and the Freese & Nichols team has completed the high level modelling analysis that prioritizes the future focused study areas for the City. City Staff and Freese & Nichols will provide an update on the program.
Background:
The City’s stormwater program and utility was initiated in 1995 to comply with the Clean Water Act to manage pollution in stormwater runoff and improve water quality. This program was tied directly to water quality requirements until 2007, when the Council increased the stormwater fee recognizing the need for new and retrofitted drainage infrastructure to solve issues with local flooding and to make system repairs. An active capital improvement program was developed at that time.
Initially, capital improvements were driven by citizen complaints and observations of flooded areas noted by City staff. Over time, the City started conducting watershed studies to look at large sections of the City and identify problems on a system-wide basis. Projects have been developed from these watershed studies and incorporated into the CIP list, along with those identified from complaints. The CIP development process is not, however, based on a comprehensive understanding of the City’s stormwater needs as not all watersheds in the City have been studied. Council directed staff to research options for utilizing contracted resources to more aggressively develop and implement stormwater improvements.
Council directed staff in early 2017 to pursue the development and implementation of a City-wide watershed masterplan. The fiscal year 2019 budget included a needed increase in the stormwater fee of $1.75 per month in order to fund the plan, to include management and completion of all watershed studies and staff expansion to support the program. Following an intensive search process, the City selected Freese & Nichols to manage the study program. The project team kicked off the program in the spring of 2019 and began developing a high level model to identify priority areas in each watershed.
The watershed team broke each of the City’s 15 watersheds into smaller drainage areas called sub-catchments. Stormwater modeling software was used to simulate rain across the City and identify which of the sub-catchments had the most significant flooding problems. The software allowed the project team to see flooding during storms that would occur with a 10, 25, and 100 year frequency. Using this information, the team prioritized each of the sub-catchments based on four criteria - structural flooding, road crossings, essential facilities, and access to isolated neighborhoods. The prioritization resulted in the sub-catchments being ranked from the most affected areas to the least.
Moving forward, the project team will begin to evaluate the sub-catchments based on the priority list developed from this high level assessment. This will allow the City to focus its budget on the highest priority areas first and then re-visit studies of lower priority areas as future budgeting allows.
In October 2019, after initial program development, the team selected additional consulting firms to assist with the study going forward. These firms will be gathering in January 2020 for a workshop to put a foundation of processes and management practices in place that will streamline their efforts as the team begins the more focused study of projects.
Issues/Analysis:
In order to evaluate the City holistically, the study needs to be completed so projects can be identified and prioritized. This presentation is an update on the progress and future timeline.
Budget Impact:
Funding for this program is included in the current budget and was projected for the next 4 years as part of the budget planning process. All funding is supported by the Stormwater Enterprise fund which comes from the Stormwater fee. There is no general fund impact from this program.
Options:
NA
Recommended Action:
NA
Attachments:
Stormwater Master Plan Update _ Jan 2020