This story was originally published in The Providence Eye, a nonprofit newsroom covering events and issues of concern in Providence. Read more at pvdeye.org.

PROVIDENCE — This year, it has rained 55 inches in Providence so far, and with the projected rainfall in the remainder of December, the accumulated rainfall will equal 2023’s 58 inches. Normal annual rainfall in Providence used to be 44 inches. As more and more storms deliver more and more rain, that water has to go somewhere.

The city has spent more money this year on flood issues than on snow removal. Stormwater management is receiving increased attention and requires even more. Stormwater flows into pipes below the street which then carry it to bigger pipes (called interceptors) and then into one of several local waterways.

Combined pipes

Many decades ago, city engineers thought it most efficient to combine stormwater and sewer wastewater (ironically called “sanitary”) into the same pipes under the city streets. All of Providence’s sewage pipes were supposed to end up at the Fields Point treatment plant, be treated, and empty into Narragansett Bay. It seemed like a good idea at the time, but it has turned into a water pollution disaster.

If the rain is heavy, the combined flows often exceed the capacity of the combined sewer and stormwater interceptors and never make it to the Fields Point treatment plant. Instead, combined sewage and stormwater flows into combined sewer outfalls (CSOs) directly into local rivers. So, untreated sewage goes into the Providence River and then into upper Narragansett Bay.

The Narragansett Bay Commission (NBC) has spent about $1 billion in the past 12 years to build combined sewer and stormwater tunnels underground to divert CSOs into tunnels to eliminate overflows into the Woonasquatucket and the Providence rivers. These tunnels have dramatically improved the water quality of both rivers and even has allowed limited shellfishing to resume in upper Narragansett Bay.

The NBC is now undertaking a third and final tunnel in the Pawtucket and Central Falls area to eliminate CSOs into the Blackstone River, which flows into the Seekonk River before reaching the Providence River.

Unfortunately, not all the CSOs in Providence have been eliminated. Many smaller overflows that are the responsibility of the city weren’t able to be diverted into NBC tunnels. These are scattered all over the city, and during heavy rainfalls they pollute such waterways as the West River and the Woonasquatucket River before flowing into the Providence River.

Water quality impairment

Providence has miles of streets where stormwater flows directly into stormwater-only pipes that discharge into local waterways. Unfortunately, stormwater flowing across residential and commercial property can produce several types of pollution that impair waterbodies:

Nutrients: Excessive nutrients can cause aquatic weed growth and algae leading to cyanobacteria blooms affecting recreational water use. The ponds in Roger Williams Park and Mashapaug Pond suffer from these sources: animal waste (dog and bird droppings), lawn fertilizers, and pollutants from large upstream parking lots. At a recent stormwater conference at Roger Williams Park, deputy superintendent of Providence Parks Brian Byrnes noted that “the future enjoyment of the ponds at Roger Williams Park depends on reducing polluted stormwater that flows into Mashapaug Pond and then into Roger Williams Park.”

Bacteria: Excessive bacteria from bird droppings on roofs and dog waste in yards can lead to fish kills, impacting recreation.

Oil and grease: Driveway runoff is toxic to all aquatic life.

Street and property flooding

Two trends have led to more street and property flooding in Providence: more building development with more impervious surfaces, and more high-intensity rain events that create flash flooding in a short period of time. Climate scientists are warning that extreme weather events like the rain events that Providence received in the past two years may be a part of our future weather patterns.

To reduce flooding in the city, major efforts have to begin to reduce existing impervious surfaces in the city and to ensure that future development limits the amount of stormwater that flows off site.

While the NBC has successfully leveraged sewer use fees to build CSO tunnels to eliminate most CSO outfalls and improve the water quality in several Providence rivers, the state Department of Environmental Management is requiring the city to take action to reduce stormwater pollution and to reduce the impact of remaining CSOs. This DEM decree is intended to get Providence into compliance with the federal Clean Water Act.

Providence is responsible for some 300 miles of stormwater, sanitary, and combined sewer pipes and hundreds of catch basins and outfalls, yet has no user fees to maintain this infrastructure.

Money presently used from the city’s general fund to maintain all its sewer and stormwater infrastructure are inadequate. The need for funds for the Providence Police Department and public schools, for example, generally trump dollars needed to clean and repair stormwater and sewer lines.

User fees

In a recent presentation on the city’s stormwater management plans, Sheila Dormody, the city’s chief of policy and resiliency, indicated that the city hopes to have an equitable stormwater and sewer user fee proposal for consideration sometime in spring 2025.

How might a sewer and stormwater user fee be applied to property owners? Much like the water fee paid to Providence Water and the sewage treatment fee paid to the Narragansett Bay Commission, a Providence sewer fee would probably also be based on a property owner’s actual sewage flows from the property.

A separate fee for stormwater would be billed to all property owners, and that fee would likely be based on the amount of impervious surfaces on a particular property that is generating stormwater flowing off the property into the street.

Applying this type of methodology across all residential, commercial, and industrial property owners in the city would generate adequate funds for the city to have a first-rate stormwater and sewer system to be eventually in compliance with the Clean Water Act; free up general funding for the city’s public schools; provide cleaner and more useable waterways in Providence for Providence residents; and reduce street and property flooding in flood-prone areas of the city.

Mitigating stormwater effects

Residents can reduce the amount of impervious surface area generating stormwater flowing onto the street or flowing directly into a stormwater and combined sewer line. Dormody said property owners will be able to reduce or even eliminate a stormwater user fee by taking actions to manage their stormwater on site. There are some relatively easy-to-implement ways to reduce stormwater runoff.

Almost 20% of Providence residential downspouts are connected to a standpipe that is tied directly into the street stormwater line. Those downspouts can be diverted onto the land.

What the city can do

More consistent and long-term outreach and public relations is needed to encourage and support on-site options for residential stormwater management. A more broad-based and sustained effort is needed to build awareness of the value and relative ease of adopting residential stormwater management.

A mechanism for providing technical assistance to property owners to install best management stormwater practices is needed. Website info is good enough for many homeowners, but some way to handle practical homeowner questions for particular properties would ensure that installations are completed properly. A link on the city’s website to video installation examples would meet perhaps much of this technical assistance need.

Another way of providing technical assistance to property owners is to develop a “Volunteer Stormwater Squad” that would be managed by a nonprofit during summer months using high school and college students. These volunteers would provide hands-on, in-person, no-cost technical assistance to property owners.

Bob McMahon has been a Providence resident since 1978. While an officer in the Navy, he participated in the recovery of the Apollo 11 astronauts in the Pacific Ocean in 1969. He has a city planning background and worked in the Providence Parks Department for 30 years, first as deputy superintendent and later as superintendent.