Green Stormwater Infrastructure

On May 1, a new Green Stormwater Infrastructure fee was included on utility services statements for residents and businesses within the City of Tucson.

This fee is assessed based on customers’ water use at a rate of 13 cents per Ccf (about $1 per month for the average residential customer), and will raise about $3 million each year to build and maintain projects throughout the city that capture stormwater runoff from public streets and parking lots, and divert it into vegetated water harvesting areas. These kinds of projects are called green stormwater infrastructure, or GSI. The new GSI Program will:

  • Provide a funding source for maintaining hundreds of existing GSI features in city neighborhoods
  • Support growing more trees and plants on streets, and in parks and public areas using stormwater as a primary water source
  • Address and reduce flooding issues on neighborhood streets

While addressing the widespread challenges mentioned above, the GSI Program will provide many additional benefits, including:

  • Put rain/stormwater runoff to beneficial use irrigating plants
  • Reduce stormwater pollution
  • Shade and cool streets, sidewalks, bikeways, and parking areas
  • Beautify neighborhoods
  • Provide an affordable alternative to building and maintaining expensive underground stormwater infrastructure

Learn More:

Frequently Asked Questions
GSI Program Proposal approved by Mayor and Council September 4, 2019 
Ordinance creating GSI Fee and Fund February 4, 2020
Memorandum to Mayor and Council February 4, 2020

Contact Form 

Infographic showing features and benefits of GSI feature with curb cut and water harvesting basin.


Frequently Asked Questions 

What is green stormwater infrastructure?

Green stormwater infrastructure (GSI) describes practices that use natural systems (or engineered systems that mimic or use natural processes) to capture, clean, and infiltrate stormwater; shade and cool surfaces and buildings; reduce flooding, create wildlife habitat; and provide other services that improve environmental quality and communities’ quality of life.

In practical terms, GSI usually takes the form of landscaped areas that capture stormwater runoff from streets, parking lots, and buildings, and allow that water to spread out and sink into the soil. It is also commonly known in Tucson as “passive rainwater harvesting.”

Why is this fee necessary? 

The fee is necessary for the City of Tucson to begin to address two critical areas of need in the community: effectively managing stormwater, and increasing urban tree canopy and vegetation while conserving our precious water resources. As the third fastest warming city in the country, increasing green canopy and strategically utilizing stormwater are measures that help Tucson become a more climate resilient city. 

The fee earmarks funding for maintaining hundreds of existing GSI features in Tucson neighborhoods. The chronic lack of funds for maintenance has become an equity issue in the installation of GSI, in that those neighborhoods who have not had the time/energy/organization/resources to maintain the features themselves have not been able to have them installed, or in some cases had them removed. The GSI fee seeks to address that inequity.

Why now?

We understand and acknowledge that so many members of our community are struggling at this time. The Green Stormwater Infrastructure fee is something that has been in development and discussion between the Mayor and Council, City staff, and the public for the past three years, and multiple elements of the launch of the program were underway well before the pandemic hit. The program addresses real issues relating to public health and welfare, and is a core strategy for the city to adapt to climate change. 

The financial impact to citizens of Tucson is designed to be very modest. The average residential Tucson Water customer will see a charge of about one dollar per month. Anyone enrolled in the City's Low Income Assistance Program will be exempted from the fee. Even with the fee, total utility service costs for City of Tucson residents (water, sewer, trash/recycling, and GSI/stormwater) is low compared to those paid by local residents outside the City. 

Is this a fee to pay for the Tucson Million Trees Campaign?

No, Tucson Million Trees is a larger effort that involves all City departments and partnerships with nonprofits and the private sector.  However, the GSI Fee will fund tree planting as part of GSI projects on streets, parks, and public properties, and it will allow the City to lead by example as we work to green our city while conserving our precious water resources.

I already harvest rainwater on my property. Why do I have to pay this fee as well?

This fee is not a charge on stormwater that is discharged from your property. It is intended to fund GSI improvements on public properties, and to manage stormwater runoff from public streets, parking lots, and public facilities. Tucson Water will continue to provide incentives for customers to harvest rainwater on their own property.

Will this increase mosquitoes?

No. All GSI built under this program will be designed, constructed, and maintained to allow stormwater to sink into the ground within 72 hours to prevent mosquitoes from breeding.

Which facilities are going to be maintained using the GSI Funds? 

The list is still being developed, but our starting place is the list of neighborhood traffic circles, chicanes, and medians on this map. Staff estimates that approximately 50-75% of the nearly 400 features identified on this map will be considered GSI (i.e. that they have a stormwater management function) and be maintained using GSI funds. As the list is refined, an updated map will be posted to tucsonaz.gov/gsi.  

How will it be decided where new GSI features are installed?

A full description of the process is described starting on page 16 of the GSI program proposal.

For the first several months of the program (starting April 2020), City staff will be focusing on reviewing upcoming projects that are already planned to see if GSI features can be added in a cost-effective way. Such projects include planned parks, greenway, and roadway improvements in Tucson’s voter-approved Parks and Connections program, and planned projects by the Pima County Regional Flood Control District.

Can my neighborhood apply to have GSI features installed?

For the past three years, Tucson Water funded and Tucson Clean & Beautiful administered the pilot Neighborhood Scale Stormwater Harvesting Program, which has offered grants to neighborhoods to plan, design, and construct small-scale GSI features. Funding for this program has been $350,000 a year, or about 1/10 the funding level of the new GSI Program. New applications for grants are currently on hold to address a backlog of projects. City staff are developing recommendations for how this program can be improved and incorporated into the larger GSI Program. It is planned that the program, and the ability for neighborhoods to apply for projects, will continue later in 2020.

Where can I make suggestions for new GSI projects?

Project suggestions, comments and questions related to the GSI program can be submitted via the contact form.