Stormwater Rate Adjustment
The City of Flagstaff has maintained a separate stormwater utility since 2003, which is funded primarily by a stormwater utility rate assessed on an Equivalent Rate Unit (ERU) basis. The current stormwater rate of $3.74/ERU generates just over $4M in revenue annually and was set in 2018 to provide debt servicing associated with the Rio de Flag Flood Control Project and to supplement the existing Stormwater Capital Improvement Program. Several events since the most recent rate adjustment have combined to make the current stormwater rate insufficient to meet current and future community needs. These events include post-wildfire flood mitigation needs, critical infrastructure upsizing needs in multiple drainage areas, deferred CIP projects identified in the 2010 Northeast Area Master Drainage Study, and rapidly increasing materials and construction costs worldwide. In this study, we intend to assess the overall financial condition of the stormwater utility and develop the appropriate rates to meet those needs.
1. How is my stormwater fee calculated?
Flagstaff residents’ and business owners’ stormwater fee is measured in Equivalent Rate Units (ERUs) where 1 ERU is equal to 1,500 square feet of impervious surface on the property, e.g., asphalt, brick or concrete pavers, buildings, compacted gravel surfaces, decks, driveways, parking areas, patios, rooftops, and sidewalks. The impervious area of properties is determined by using aerial photographs and information in the city’s Geographic Information Systems (GIS) along with parcel lines from the county assessor's office.
The current fee for residents within the city is $3.74/ERU. The proposed rate adjustment would raise this fee to $10.33/ERU by 2029 if Proposition 441 passes in the November 2022 election or $11.39/ERU by 2029 if it doesn’t. (See Adjustment Study to the left for more information about these two scenarios.)
2. Why are my rates going up?
Increased fire and flood events over the past few years have made current infrastructure insufficient. The resulting demand on operations – staffing and equipment – has also surpassed current capacity.
Increasing the stormwater rate will allow the city to address recent drainage/flooding issues caused by 2019 Museum Fire and 2022 Tunnel and Pipeline Fires. Pre-season flood mitigation – sandbags, jersey barriers, clearing out drainages – are required to proactively avoid flood events during summer monsoon season. Regular maintenance work to clear out flood detention basins will be required. This will also allow some of the Capital Improvement Projects (CIP) identified in the 2010 Northeast Area Master Drainage Study (NEAMDS) to move forward, which will reduce flood response operations costs. The top rated 37 projects identified by the NEAMDS have a current cost estimation of $74.4 million. The current annual capital funding allotment for stormwater is $600,000 per year, which does not cover the needs.
The new retention basins for flood mitigation will require regular maintenance, such as Spruce Wash and Shultz Creek, and will also be covered by the proposed rate increase.
3. What is the increase being spent on?
The stormwater section has incurred increased responsibilities in flood mitigation and flood response, with ongoing maintenance requiring dedicated staff and equipment. The proposed rate increase would be used to increase capital funding for permanent flood mitigation measures such as larger storm drains and improved water detention facilities. Priority project areas in the next 6 years include the Rio de Flag, spot improvements, Museum and Pipeline Fire burn scars, current projects identified in the NEAMDS study, and future projects as they arise.
The additional funding would also go toward increased operating cost for pre-season flood mitigation, staffing and equipment cost, and master planning. Without significant increases to the rate, the stormwater fund will not be able to meet the community’s stormwater needs within the next six years.
4. Why is this rate increase important?
The rate increase allows necessary work to continue in Flagstaff as climate change presents more frequent and intense wildfires and flooding. The upgrades to infrastructure will better equip our community to withstand post-wildfire flooding in the future. Flood waters, along with the mud and debris carried with them, pose an environmental and health hazard risk, as well as infrastructure and property damage. The rate increase will support pre-flood mitigations, flood response and work toward infrastructure to mitigation future flooding, keeping water in channels designed to handle the flows.
5. Will this rate increase cover all of the Stormwater section’s needs?
The rate increase will fund a portion of stormwater infrastructure needs. Other infrastructure needs will be addressed within the capital budget, bonds, and grants. See the rate adjustment study to the left for graphs that break down how different funding sources will be used.