Updating Our Rates: Environmental Services Rate Study

On this page, you will learn about the work BES is doing to update the way we charge our rates so that sewer and stormwater rates accurately reflect the cost of serving each customer.
On this page

Since 2019, Environmental Services has been conducting a rate study or cost-of-service analysis, which is a technical analysis comparing our rates and charges with peer agencies. The analysis focuses on developing recommendations for updating how we charge our ratepayers to ensure billing is more consistent with service costs.

Council Hearing to Be Held on November 29, 2023.

The rate study hearing that was previously scheduled for November 8, has been rescheduled for November 29. Please see below for more information. 

Noteworthy Changes 

The rate study ordinance that will be considered on November 29th has been updated from previous ordinance packages. The current ordinance now maintains the status quo for overwater structures so that they are not billed for stormwater services. Please see below for links to the updated ordinance.

If you would like to receive updates about the Rate Study, including relevant City Council dates, please sign up to receive project updates.

Below are important documents and resources relevant to the City Council Session. 

  • Council Packet: Includes a memo summarizing the recommendations and proposed changes to Portland City Code Chapter 17.36. 

  • Overwater Structure Memo: This memo summarizes stormwater charge practices for floating homes and overwater structures examined in Environmental Services' Rate Study Report. 

  • Overwater Structure FAQ: Contains answers to frequently asked questions raised during conversations with overwater structure homeowners. 

Council Process and How To Participate

The review and adoption process will be a typical council process: Environmental Services will present, Council will ask questions, and they will hear public testimony. After testimony and discussion, Council can choose to vote on whether to adopt the package. They can also choose to amend the package or reject the package. If they choose to approve the recommended changes, they will then be sent to a second reading one week later.   

Council can reconsider their decisions after adoption. To do so, City Staff or a member of Council would need to bring the item to Council for discussion and a vote.  

You can learn more about this process on the Council Clerk's webpage

Public comment is encouraged at all Council meetings: Public comment is allowed and encouraged for the first reading of all ordinances. People are asked to sign up ahead of time with the Council Clerk to testify. Find out how to testify on the council webpage. 

What does BES recommend?

BES staff is submitting a packet of recommendations to Council for consideration. The recommendations will offer benefits to many lower-income ratepayers and small businesses; incentivize development of smaller more affordable homes; and remove a key source of burdensome costs for our customers.

The recommendations are revenue neutral and do not raise rates overall. They benefit BES customers, not BES – we collect the same amount either way.  

  1. Adjust all rates to ensure that all customers are billed fairly based on the cost of serving them. The “cost of service” principle is the underlying basis for all recommendations. 

  1. Shift our rates to charge more for stormwater services and less for sanitary services. Stormwater is rain, and rain has significant impacts when not managed – from flooding homes, businesses, and streets to polluting waterways. The rate study found BES has made substantial investments in its stormwater system, and so needed to shift its rates to charge more for stormwater services and less for sanitary services. 

  1. Promote affordability for most residential customers: Eliminate flat stormwater charges for homeowners and instead adjust charges so that smaller homes are billed less, and larger homes are billed more. Previously, all single dwelling unit properties were charged one flat rate for stormwater. Tiering rates will lower costs for approximately 80% of single dwelling unit residential customers.  

  1. Improve systems development charges to simplify the application process and incentivize affordable housing development. These changes will cut sanitary and stormwater SDCs by approximately 25% for smaller single dwelling unit homes. Similar benefits will be seen for smaller “missing middle” multi-family housing SDCs. 

  1. Lower the cost to connect to our system. These connection charges can often shock ratepayers with thousands of dollars in unexpected charges. Certain connection charges (i.e. line and branch or conversion charges) are a legacy of the +30-year-old mid-county sewer project and still in City Code. These code requirements can result in huge bills - sometimes tens of thousands of dollars - when a property first connects to the sanitary system. The recommendations retire these code requirements now that development needs and circumstances have changed.  

  1. Expand our Clean River Rewards program to more customers and make it simpler to register. This program provides up to a 35% discount on stormwater bills for customers that disconnect their downspouts or otherwise manage stormwater on their property. The proposed changes will allow customers to maintain their discount eligibility while they resolve minor compliance issues.

  1. The rate study recommended that BES bill overwater structures based on the cost of serving them – calculated by the consultant as 88% of the rate for properties on land. Customers with overwater structures are users of the stormwater system and BES incurs a cost to serve them. Overwater structures were charged for stormwater service but are currently exempt from stormwater charges per council direction in 2018.  NOTE:  Recommendation #7 was not included in the ordinance language at the direction of the BES Commissioner.

  2. The rate study recommended that BES bill Drainage District customers based on the cost of serving them – calculated by the consultant as 96.6% of the rate for properties outside the Drainage Districts. Drainage District customers are users of the stormwater system and BES incurs a cost to serve them. Drainage District customers are currently charged 65% of the cost of service per an IGA reached with the Drainage Districts in 2013.  

  3. Phase in rate changes over three years to mitigate rate impacts to highly impacted customers.  

What did BES hear from the public? 

BES staff conducted an extensive outreach effort to vet these of recommendations with our customers and the broader community. Staff used this community feedback to refine the recommendations package being brought to Council. In total, BES staff heard from hundreds of people and held more than 40 outreach events. 

  • BES staff heard broad support for the changes from community organizations, neighborhood association and business district representatives, environmental advocates, the development community, and the Portland Utility Board. The proposed changes are broadly beneficial to lower income residents and most homeowners. We anticipate letters of support and testimony in favor from these groups. 

  • BES staff heard concentrated opposition from customers with overwater structures. The rate study recommends that customers with overwater structures resume paying for the services they use.  

    • This customer group represents about 180 accounts out of more than 185,000 and are about 0.2% of our stormwater customer base.  
    • Council paused charging for this group in 2018 pending the results of the rate study. The rate study recommends resuming those charges, at a rate that is 12% lower than customers on land.  
    • Per the independent consultant: “…by discharging directly into receiving waters they [overwater structures] have the potential to significantly impact water quality and are among the most benefitted properties from upstream flood and water quality controls.”  

What is a rate study? 

A rate study is a routine technical analysis that is meant to ensure that the rates a utility charges accurately reflect the cost of serving each customer. Rate studies are regarded as a best practice in the utility industry and are conducted on a regular basis. Typically, they involve an assessment of spending, a comparison to peer agencies, and recommendations for ensuring that rates are aligned with costs of service for each customer. 

Why did BES conduct a rate study? 

The Portland City Council passed an ordinance in 2018 that directed BES to conduct a rate study. That Council ordinance included a specific direction to examine how overwater structures such as industrial docks and floating homes should be billed. In addition to Council’s direction, BES has been overdue in conducting a rate study, which is routinely done by utilities every five to eight years. BES’s last rate study was in 2005.

BES hired Galardi Rothstein Group, a respected independent consultant specializing in infrastructure finance and utility management and rate and fee setting to conduct this new rate study. 

Investing in a Healthier and More Resilient Portland

The miles of pipes, pump stations, and treatment facilities that make up our sanitary sewer and stormwater system protect public health and the environment, promote economic development, and support community and climate resiliency. This year, Environmental Services will invest $727 million* to operate, maintain, and repair this infrastructure. Large portions of the system were built more than a century ago. Significant investments in upgrades and repairs are essential to meet regulatory requirements and the needs of our growing population and respond to a changing climate.

*Based on the 202-24 budget.

Current Challenges

Many components of our pipes and pump station network and the Columbia Boulevard Wastewater Treatment Plant are reaching the end of their operational life. Maintenance costs are increasing, and there is a risk of substantial failures if repairs and upgrades are not made. These significant investment needs are compounded by rising costs due to supply chain issues, increasing labor costs, and an inflationary environment that is driving up the cost of every project.

Previous Outreach Presentations

Technical Discussion Sessions

In March of 2023, representatives from community organizations, commercial and industrial businesses, and other interested Environmental Services ratepayers participated in technical discussions about the way customers are charged for our services.

Engagement with community members and ratepayers will inform how Environmental Services implements the updated rate structure. The technical discussion sessions allowed for technical conversations while also giving space for people from non-technical backgrounds to contribute and learn. 

Please see below for a link to the Technical Discussion Session Presentation as well as summary notes from the sessions.

This document summarizes the community feedback received during Environmental Services Rate Study Technical Discussions Sessions held on March 21 and 23, 2023.
This document shows the presentation slides used during the Environmental Services Rate Study Technical Discussions Sessions held on March 21 and 23, 2023.

Drainage District Informational Presentation

On June 14, 2023, Environmental Services staff held an informational presentation and discussion session with ratepayers in the Drainage Districts.

Presentation slides for the Rate Study presentation and discussion with the Drainage District on June 14, 2023.

Development Review Advisory Committee Presentation

On August 17, 2023, Environmental Services staff gave a presentation to the Development Review Advisory Committee. This presentation focused on Service Development Charges (SDCs) and other Connection charges.

On August 17, 2023, Environmental Services staff gave a presentation to the Development Review Advisory Committee on the Rate Study.

Estudio de Tarifas Presentación en Español

Empleados de BES presentó a un grupo de usuarios sobre el studio de tarifas en Español. Las láminas están bajos de la presentación.

Sign Up for Project Updates

Sign up for updates on how we set and adjust our rates through our free GovDelivery subscription service. These updates are the best way to stay informed about what's happening and what to expect. You can also sign up for updates on other projects and topics from Environmental Services.

Resources and Documents

The Preliminary Report contains the technical findings and rate and fee design options developed as part of the rate study.
The Environmental Scan Memorandum summarizes the preliminary findings of the Environmental Scan, including key themes that emerged from initial policy discussions and technical workshops.
This Utility Benchmarking Memorandum summarizes the results of the rate study utility benchmarking exercise. Environmental Services' rate-setting practices and rates were compared against nine benchmark utilities.
The Rate Study Packages Memorandum summarizes the numerous alternatives for designing sanitary sewer and stormwater user rates, system development charges, and stormwater credits.
This memo summarizes the full complexity of stormwater charge practices for floating homes and overwater structures examined in Environmental Services' Rate Study Report.

City Council Documents

Below is the set of documents submitted for the City Council Session.

This memo summarizes the final rate study recommendations based on the 'Preliminary Report: Sanitary Sewer & Stormwater Comprehensive Rate Study' and 'Rate Study Community Engagement Summary.'

This document summarizes the proposed changes to Portland City Code Chapter 17.36 as a result of the Rate Study and community engagement.

Posted November 21, 2023 2:24 pm

This document includes the proposed changes to Portland City Code Chapter 17.36 as a result of the Rate Study and community engagement.

Posted November 21, 2023 2:24 pm

Frequently Asked Questions: General

What is a rate study?
A rate study is a financial evaluation process where a utility, such as Environmental Services, reviews its rate structure to make sure that the cost for ratepayers is proportional to their impact and use of the system.

What are Environmental Services' desired goals and outcomes?
Some of the desired goals and outcomes from this rate study and engagement process are to create a rate structure that:

  • recovers costs in proportion to the demands various customer classes place on the system;
  • considers the impacts on all Portlanders;
  • reflects Environmental Services' values;
  • is administratively feasible to implement;
  • addresses and considers affordability concerns;
  • removes barriers to accessing services and incentive programs.

What is Environmental Services proposing to change?
Environmental Services has compared our rate structure to industry benchmarks and best practices. Environmental Services will review sanitary sewer rates, stormwater rates, system development charges, other fees, and the Clean River Rewards discount program as part of this rate study process. Before formally proposing changes to our rate structure, we will provide options for potential revisions during the public engagement process.

What are some other opportunities to learn more and give feedback?
All opportunities to learn more and give feedback will be posted under the Upcoming Engagement Opportunities section of this page. Environmental Services hosted Technical Discussions and Office Hours and is now hosting Informational Sessions. To stay up-to-date on the rate study process, you can sign up for updates on how we set and adjust our rates through our free GovDelivery subscription service.

Why is Environmental Services recommending adjusting rates, so customers are charged more for stormwater and less for sanitary costs?
Environmental Services is recommending adjusting rates to match the cost of providing sanitary and stormwater services. Since our last consultant-led rate study in 2005, Environmental Services  has significantly invested in capital assets, such as the Big Pipe, the Secondary Treatment Expansion Program, other stormwater assets, as well as  stormwater operations and maintenance costs. Our rates should shift to more closely match what Environmental Services spends on sanitary and stormwater services.

How are Environmental Services rates set?
The first step for setting rates is identifying the revenue necessary to achieve bureau goals based on a multi-year financial forecast. Then, Environmental Services subtracts all of the other ways that the bureau collects money other than via rates - such as fees and system development charges - to arrive at a “rate revenue requirement.” 

Once the rate revenue requirement is identified, Environmental Services rates are set using a cost-of-service methodology. The methodology seeks to recover costs are proportionate to spending from new and existing users of the system.  Spending is allocated to each system (sanitary and stormwater) based on the reason for the expenditure. Lastly, those costs are allocated to customers based on measurable service characteristics. 

Find out more about Environmental Services’ Sewer and Sanitary Stormwater Rates and Charges, as well as the annual rate study, which explains how rates are set in greater detail, on the webpage.

What is the specific rate currently charged to each customer class?
Customers are charged based on the rate ordinance adopted by Council. Rates by customer class are available on the Sanitary Sewer and Stormwater Rates and Charges webpage.

What is the timeline for implementing rate changes?
Changes to the rates from the rate study will be implemented July 1, 2024. It is important to note that rates increase every July 1 to account for inflation, maintenance and operations, and increases in capital costs. This increase is addressed during the budget process.

Is phasing in the change possible?
Yes. The rate changes will be phased in to mitigate abrupt bill increases, particularly for the most impacted customer classes. Environmental Services staff have not determined the phase in schedule but will do so prior to submitting the proposal for Council consideration.

What is an Equivalent Service Unit? 

An Equivalent Service Unit, or ESU, is proposed as a new component of the stormwater bill. This component of the bill is based on the average number of occupants in a dwelling. An ESU will be calculated for each property based on the following information: 

  • 1 single dwelling or a duplex – 1 ESU per unit 
    • A single dwelling unit serves as the basis for determining an ESU.  
  • 1 multi-dwelling unit – 0.65 ESU 
    • This is due to the number of occupants per multifamily dwelling being approximately 65% of that of single dwellings.  
  • 2,400 Square Feet for non-residential – 1 ESU 
    • Since commercial and industrial customers do not have dwelling units, they are charged based on impervious area. As one single dwelling equals both 1 ESU and 2,4000 square feet of impervious area, this is a proxy for impact by commercial and industrial customers. 

This component will cover 20% of the stormwater costs related to items like regulatory needs, right-of-way runoff, and natural area maintenance. 

How will the Clean River Rewards Program Change?

Clean River Rewards is being updated to align with current BES stormwater objectives to safely collect, convey and dispose of stormwater at the source and align with updated billing criteria for single-family and small multi-family properties.

Customers currently enrolled in the Clean River Rewards program won’t notice much of a change and won’t have to do anything to maintain their discount when the program changes. The Clean River Rewards program will continue to discount up to 35% of the total stormwater charge for each property that manages some or all of their stormwater on site. Program changes will apply to anyone registering for a Clean River Rewards discount on or after July 1, 2024.

Proposed changes to the program include:

  • Allow customers to register for the discount regardless of an outstanding balance on their water/sewer/stormwater bill or a minor environmental noncompliance issue. BES is currently evaluating what constitutes minor noncompliance.
  • Drainage District customers who safely manage some or all their stormwater onsite will now be eligible to register for a Clean River Rewards discount.   
  • Trees will now be eligible for a larger discount.   
  • A simplified registration process for large multi-family, commercial, and industrial properties that were required at the time of development to manage stormwater onsite. The process will be as easy as checking a box indicating there is a stormwater Operations & Maintenance (O&M) form for the property and providing the O&M number.
  • Stormwater directly discharged into the Willamette River or Columbia Slough with no pretreatment will no longer be eligible for a CRR discount.

Eligible customers will continue to be required to register to receive a CRR discount and registrations for large multifamily, commercial, and industrial properties will continue to be verified by BES staff before the discount is applied. BES will also continue to periodically audit CRR registrations to ensure the ongoing accuracy of CRR discounts.

BES plans to open a public comment period on the updated Clean River Rewards administrative rule (ENB-4.16 Clean River Rewards) in February 2024.  

What are Drainage Districts?
Drainage Districts are a series of governmental entities that are separate from the City of Portland and Environmental Services. These Districts provide services, including levee maintenance, flood mitigation activities, and stormwater conveyance from the managed floodplain along the Columbia Slough and Columbia River. There are three drainage districts that are within Environmental Services’ service area along the Columbia River and the Columbia Slough. For more information, please visit the Multnomah County Drainage District website.

How will rates change inside the Drainage Districts?
Rates will be adjusted to reflect the cost of providing services within the Drainage Districts. Currently, customers within the Drainage Districts only pay the off-site portion of stormwater charges. This currently equals 65% of the stormwater rate that is paid by customers outside the Drainage Districts. Rates will increase to match customers outside the Drainage Districts (with a small discount for some services that are provided by the Drainage Districts themselves). This will result in rates that are about 96.6% of the stormwater rate customers pay outside of the Drainage Districts. All other proposed changes impact Drainage District customers in the same way as all other customers.

If Drainage Districts manage stormwater, why is Environmental Services looking to bill people for stormwater management inside the Drainage Districts?
Environmental Services and Drainage Districts provide separate but complementary services. Environmental Services provides stormwater management, compliance with water quality regulations, and stormwater runoff management across the entire city, including within the Drainage Districts. In addition to services provided within the Drainage Districts, many costs for Environmental Services are spread across all customers within the city, such as debt service and overhead costs. Environmental Services bills customers inside the Drainage Districts for services provided to all customers within the city, but not for services provided by Drainage Districts.

Will Clean River Rewards discounts be available for customers in the Drainage Districts?
Yes. Customers in the Drainage District will be eligible to register for a Clean River Rewards discount if they are safely managing some or all of their property’s stormwater on their property.

Why have customers in the Drainage Districts paid a different rate than other customers?
Historically, the rate for Drainage District customers and other customer types (like overwater structures) has been set by policy rather than set by the cost of providing services to those customers. In 2013, Council adopted an intergovernmental agreement with the Drainage Districts to charge the off-site portion of stormwater rates to customers within the Drainage Districts. The updated rates ensure that all customers pay stormwater rates in proportion to the cost of providing service.

Why do properties that discharge directly to receiving waters with no local conveyance need to pay a stormwater management charge?
The stormwater system is constructed to benefit all Portlanders by managing stormwater runoff from public and private properties. Properties that discharge directly to receiving waters (streams, rivers, or other water bodies) benefit from the overall stormwater system in many ways and therefore pay stormwater rates. Additionally, debt service payments and other costs benefiting all customers in the city are recovered from all customers. While the customer may not be directly using the stormwater conveyance system, they benefit from the water quality and conveyance mitigation activities as any property in the city does. Environmental Services is also partly responsible for the water quality in the Willamette and Columbia Rivers, which is impacted by those directly discharging.

How will the changes impact Accessory Dwelling Units (ADUs)?
Rate changes will not impact ADUs differently than other dwelling units. For stormwater rates, BES currently charges ADUs no additional impervious area, they are included in the class average impervious area for single family customers. In the new structure the site impervious area including the house, ADU and any other pavement would determine the single-family stormwater rate tier assigned to the property as a whole.

If a patio or garage roof drains locally on to the property, why does it count as impervious area?
Environmental Services charges all impervious area even if runoff is managed on-site. If a property’s runoff is fully or partially managed on-site, customers may register to receive a Clean River Rewards discount.

How are people irrigating or watering their yards being charged?
Customers are charged sanitary rates only on flow that enters the sanitary sewer system. Environmental Services recognizes that irrigation and watering yards does not go into the sewer system and has several processes in place to ensure that customers are not charged for irrigation. Please visit the Sanitary Sewer and Stormwater Rates and Charges webpage for more information.

Did Environmental Services analyze how the increase in working from home is shifting costs for property owners?
Changing demand patterns, such as the increase in working from home, are factored into rate forecasts. The changing demand does not change how sanitary costs are allocated, but it will affect individual customers’ bills.

How will the proposed changes to the rate methodology affect incomes in Portland, particularly for low-income and vulnerable communities?
The proposed changes to Environmental Services’ rate structure will generally have a positive cost impact for 80% of single-family residential customers. Single-Family residential customers will be broken up in to four “tiers” according to the amount of impervious area on their property. Each tier will be charged a different rate based on the amount of impervious area.

  • Tier 1 properties (20%), or those with minimal impervious area, can anticipate a reduction of approximately 18% ($15 per month)
  • Tier 2 properties (60%), or those with average impervious area, can anticipate a reduction of approximately 1% ($1 per month)
  • Tier 3 properties (20%), or those with larger houses or high amounts of impervious area, can anticipate a slight increase in their bill - approximately 16% ($13 per month) 
  • Tier 4 properties are very large properties that will be measured based on actual impervious area. They will see fairly significant increases depending on their actual impervious area.

Generally, the proposed changes to multi-family residential rates would increase the share of the bill charged for stormwater and decrease the share of the bill for sanitary service. Multi-family rates are very dependent on the specifics of each property - the number of dwelling units, the amount of surface parking the size of the roof top area, etc.  In general, higher density properties with large numbers of people and a small amount of stormwater billable area may see some bill increases. Middle density and lower density properties would see no change or some decrease in their bills.

What are the impacts of the proposed changes on housing affordability and eviction rates?
The expected impacts of the proposed changes will not negatively impact housing affordability and eviction rates. Overall, housing affordability and eviction rates are influenced by many factors that have a far larger impact than the sewer and stormwater utility bill. Additionally, the changes proposed in the rate study reduce the overall cost burden on residential customers as a whole. While the specific change for a customer will depend on various factors, most residential customers will pay similar amounts as they currently do.

Why does Environmental Services use discount programs rather than develop a rate structure that considers people's incomes? 

Environmental Services currently charges rates for sewer and stormwater services based on usage, which is an industry standard and longstanding city practice. Discount programs and financial assistance programs are also industry-standard means of helping ratepayers who are unable to pay their bills. 

It is possible to create a utility rate structure that takes income into account. There are some limited examples of cities working on this type of structure. However, there are several obstacles to crafting a rate structure that considers incomes. First, administrative feasibility is challenging. It would require additional staffing and significant resources to develop and implement this new system.  

More importantly, though, charging based on income would require collecting far more personal financial data than the bureau currently collects.  The amount of information that would be needed to identify low-income residents and confirm their income levels presents significant privacy concerns. 

In conclusion, shifting to a rate structure that considers people’s incomes is possible and it may offer a promising alternative for furthering city equity and fairness goals.  However, there are also significant barriers to moving forward with this concept. BES may look into this model more deeply following completion of this rate study.

How can we ensure that people can access assistance programs if the rate structure does not automatically take income into account? 

Environmental Services is currently working with the Portland Water Bureau on this exact question. We recognize the need to expand the assistance we offer so that it is better funded for vulnerable people, extends further up the income ladder to reach struggling people who are currently ineligible, and lowers barriers to access so that people who qualify can be enrolled quickly, simply, or even automatically. 

How does Environmental Services’ work and Services benefit the Columbia River? 

Environmental Services conducts a substantial amount of work that directly benefits the Columbia River. First and foremost, our work protecting and improving water quality in the Columbia Slough and Willamette River watersheds directly impacts water quality in the main channel of the Columbia River because these watersheds flow directly into it.  

We also work to improve and protect water quality in the Columbia River itself: 

  • The Columbia Boulevard Wastewater Treatment Plant releases cleaned wastewater to the Columbia River near West Hayden Island. In order to keep the Columbia River clean and safe, and in accordance with our state and federal permits, we conduct regular monitoring and testing to make sure our discharge water is clean and cold, partner with researchers to study emerging contaminants to see how we can keep them out of the Columbia, and regularly maintain our outfall, so it is operating properly.   
  • We lead the City’s coordination on upgrading the Columbia River Levee, managed by the four drainage districts led by Multnomah County Drainage District (MCDD) and the US Army Corps of Engineers. The levee keeps the Columbia Corridor, an economic engine for the state, including the Portland Airport, safe from flooding. We also work with federal and regional partners to identify areas of environmental restoration and stormwater management on the Columbia River side of the levee. The opportunities are limited, but they include identifying areas of shallow water habitat and areas to add large wood for habitat. 
  • With the Office of Government Relations, we partner with Tribal Nations on salmon issues in the Columbia. This includes representing the City in the Columbia River Treaty negotiations, an international treaty between the US and Canada, ratified in 1964, that manages flood risk in the Columbia River. The Vanport flood was the major impetus for the Treaty. Key provisions of the Treaty that primarily benefit Portland expire in 2024, and the US and Canada have been working for 10 years to modernize the Treaty and update those provisions. Portland has engaged to ensure ongoing flood protection to Portland, and with the Columbia River Tribes, has strongly advocated to include Ecosystem Function as a component of flood protection to support salmon and steelhead and climate resilience. The US and Canada are still in negotiations. 
  • Where needed, we serve as technical experts to the City for issues related to stormwater, flooding, natural resources, salmon, wildlife, and climate resilience in the Columbia. For example, we have been involved in the past and current Interstate Bridge Replacement projects, including environmental mitigation sites and stormwater management plans in Portland. 
  • BES has taken the lead on legacy conflicts between stormwater infrastructure and the Columbia River levee, upgrading the infrastructure (such as outfalls) to comply with new levee standards from the Army Corps of Engineers. 

Frequently Asked Questions: Overwater Structures

Why do floating homes and overwater structures need to pay for stormwater management if the water from those structures goes directly into the river?

Environmental Services rates are not solely – or even mostly – based on direct impacts to water quality. There are many customers throughout the city who are not directly connected to the City's stormwater system. However, all Environmental Services customers use the stormwater system every day. People go to work and school, get groceries, enjoy cleaner rivers and restored natural areas. All of these are possible partly due to the services Environmental Services provides.

Environmental Services rates are based on a cost allocation method that attempts to take into account direct impacts where possible. However, it is not always possible or cost-effective to directly determine the exact impact of each individual on the City’s stormwater system and local water bodies. Instead, Environmental Services attempts to allocate costs on a rational basis so that each property shares equitably in the costs to manage our shared infrastructure and water bodies. These rates are in exchange for a service and are not considered taxes.

Similar to on-land customers that directly discharge runoff to receiving waters, properties with overwater structures benefit from the stormwater system as a whole. The stormwater system is constructed to help all Portlanders by managing stormwater runoff from individual properties and the rest of the city, including roads, natural areas, and other parts of the city that benefit everyone. Additionally, debt service payments and other costs benefiting all customers in the city are recovered from all customers. Finally, these properties have an impact on water quality in our rivers and waterways. If a floating home or overwater structure mitigates their stormwater runoff, much like properties mitigating their stormwater runoff on land, they may be eligible for Clean River Rewards.

People using overwater structures have a stake in the proper functioning of the stormwater system as a whole. The proposed rate changes for overwater structures are reasonable proxies used by stormwater utilities throughout the country for measuring both the impact on a system of each property as well as the responsibility we all share for supporting the proper maintenance and management of our stormwater infrastructure and local water bodies that we hold in common.

Does BES have jurisdiction to bill Overwater Structures for Stormwater Services?

Yes, properties with overwater structures and people who visit them, live on them, or use them for work, use the City’s stormwater system. As the manager of the citywide stormwater system, BES spends money to serve these properties – including the area over water.

In addition, BES is responsible for ensuring compliance with a range of state requirements for protecting water quality. BES is the Designated Management Agency (DMA) for DEQ’s TMDL requirements which serves to help lesees meet their water quality compliance terms for Department of State Lands (DSL) leases for overwater structures. Billing to recover costs for managing compliance is consistent with BES' role and responsibility to protect water quality in Portland.

Is Environmental Services collecting more money by billing overwater structures?

No. The changes are revenue-neutral. Some customers will see an increase in bills, and some will see a decrease. Environmental Services will not collect additional revenue from the proposed changes. Environmental Services is instead proposing that the costs of managing our system and providing of services be more fairly and equitably recovered from all of the system’s users in line with the rate study recommendations. If Environmental Services were to exempt overwater structures from the proposed stormwater rate, those properties would not be paying a rate that reflects the cost Environmental Services incurs to serve them.

What is the impact of runoff from overwater structures on water quality?

All land uses can generate stormwater pollution. When water moves across the landscape, it can pick up and transport pollutants to nearby waterbodies. Buildings themselves can be a source of contaminants, particularly roofing materials. Researchers testing runoff from residential roofs have found roof runoff to contain high concentrations of heavy metals, Polycyclic aromatic hydrocarbons (PAHs; a large class of organic compounds), phthalates, sediments, and biocides. In the case of asphalt shingles, copper is commonly added as a biocide that is released over time to prevent the growth of moss and algae. The stormwater running off these roofs will pick up some of the added copper. The galvanized metals used in metal roofs have a thin zinc layer that provides corrosion resistance. Runoff from metal roofs has also been found to contain high concentrations of copper and zinc. Without treatment, roof runoff can be source of stormwater pollution that can harm fish and other aquatic life. 

Environmental Services staff specializing in water quality and stormwater compliance have reviewed the substantial scientific literature confirming the impacts on water quality from roofing materials and prepared a bibliography of relevant sources.

Why are slatted docks included as stormwater billable area?

Environmental Services staff are seeking to add slatted docks that are over water to a list of surfaces that are considered billable because of their impacts on water quality. Environmental Services does not consider slatted docks to be impervious area. Wood and composite materials collect dust, debris, and pollutants like any other urban surface. When these pollutants wash into waterways without contacting materials that mitigate pollution and clean the water, it has an impact on water quality. In addition, the wood, metal or composite materials can leach pollutants and introduce microplastics and chemical compounds into waterways as they break down over time. Because of this direct impact on water quality, BES is proposing that slatted docks be included as stormwater billable area.

How can overwater structures qualify for Clean River Rewards? 

Like all properties in Portland, floating homes can qualify for Clean River Rewards (CRR) by meeting the requirements for the Stormwater Management Manual (SWMM). It is up to the owners to determine if it is technically feasible to install a stormwater management facility on an existing floating home or overwater structure.

For properties that discharge directly to the Willamette River, Columbia River, or the Columbia Slough, the requirement is to filter the water quality storm event (as defined in the SWMM). This can be accomplished with a vegetated planter designed for stormwater management or a proprietary device that site runoff is piped through before discharging to surface waters. 

Floating homes are typically part of a larger community. They are considered to be a multifamily property for the purposes of billing. This occurs because the property receives one Environmental Services and one Portland Water Bureau connection for the overall community. Multifamily properties, including floating home communities, can qualify for CRR Discounts on the overall impervious area that is managed. This means that a floating home community may receive a discount on its parking lot or clubhouse, for example, even if the overwater structures are unable to manage stormwater runoff on-site. For many floating home communities, at least some CRR discounts should be available. 

There are many properties throughout Portland that are unable to qualify for CRR discounts due to the specific circumstances of that property. For example, a house may be located on a small lot without adequate room for on-site stormwater management. In other locations, such as the SW Hills, the topography may be too steep, or ground conditions may not be suitable for infiltration. Floating homes are similar in that their specific location may not be conducive to on-site stormwater management for the overwater portion of the property. However, significant portions of many floating home communities likely do qualify for CRR and can see potentially substantial reductions in the stormwater portion of their bills as a result. 

Environmental Services staff are tracking new methods for treating stormwater on-site for overwater structures. Small planters have shown some promise in this area and may be an option. There are also cartridge systems that fit into downspouts that could potentially meet Stormwater Management Manual standards as well. Staff would be happy to work with any floating homes community on piloting potential methods for treating stormwater runoff from floating homes. In the meantime, if a floating home community can show that an overwater structure is meeting Stormwater Management Manual guidelines, then that overwater structure would be included in the CRR discount.