A River Runs Through It

Spring 2020

A CHANGING CLIMATE, INCREASING DEVELOPMENT, AND AGING, ANTIQUATED DAMS ARE PUTTING RHODE ISLAND CITIES AND TOWNS IN PERIL

By Bob Gulla | Photographs by Monica Allard Cox

THE DAME AT THE SOUTHERN END OF THE  John L. Curran Lower Reservoir in Cranston is, like so many dams in Rhode Island, tricky to find. Tucked away down a dirt road and a few hundred feet along a woody footpath, the structure reveals itself quietly, a modest earthen dam lining the southern shore of the reservoir.

The dam is a few hundred feet long and about 12 feet high on the downstream side. The downstream embankment is steep and wooded, heavy with brush, weeds, rocks, and small trees. At the base of the embankment, there’s the lower-level outlet, where water runs through the dam.

The crest of the dam is a worn dirt path about 5 feet wide. At the end of the crest lies what is called the spillway, an exit point that keeps the water level from rising too high. Walking along the crest, you can hear the gurgle of the reservoir’s run-off.

At the spillway, branches of scrub trees and weedy growth hang low over the moving water. Nearby, a few gadwalls wade in the dark, cold water, diving for aquatic vegetation. It’s sunny, but the shallow edge of the reservoir is rimmed with a thin sheet of ice.

The Curran Lower empties into Clarke Brook on the downstream side, which in turn flows briskly into the North Branch Pawtuxet River and eventually the Pawtuxet River proper. A few miles later, the Pawtuxet meets the Providence River at Pawtuxet Village in Cranston, which dumps into Narragansett Bay on its way to the ocean. Along the way, it winds through some thickly populated areas, making the Curran Lower Reservoir, like many of the state’s inland water bodies, rather consequential.

At this moment, though, it is wearing a peaceful guise. The idle hush of a Rhode Island winter has given the earthen dam a quiet, if deceptive, beauty. Because, the fact is, all is not well here.

THE REALITY OF THE SITUATION

State and federal inspectors have warned of problems with Curran Lower, a century-old structure owned by the state, since the early ’60s. The spillway is cracked and worn. The lower-level outlet, designed to relieve pressure from pending floodwaters, is clogged with debris and completely ineffective. Deep-rooted trees are punching holes in the dam itself, enabling water to seep through where it shouldn’t.

In 1981, the U.S. Army Corps of Engineers determined that flood conditions could lead to a breach. The report recommended repairs within one year, but those repairs were never made. The Rhode Island Department of Environmental Management (DEM) inspected the dam in 2010 and determined the dam was unsafe, meaning there was an unreasonable risk of failure that could result in death. Today, it remains damaged and dangerous, with no resolution in sight.

The dilapidated Curran Lower Reservoir dam has been a concern for decades.

Rhode Island has 669 inventoried dams across the state. Of those, 96 are classified as high hazard and 82 are deemed “significant” hazards.

“It really is in poor condition,” DEM dam safety expert Stacey Pinto says, observing the structure. “It’s beautiful, and it’s created a nice natural area, but it’s also very delicate, if that’s the right word. And it’s in dire need of repair.”

Rhode Island has 669 inventoried dams across the state. Of those, 96 are classified as high hazard and 82 are deemed “significant” hazards. According to DEM’s definition, “high hazard” means that “failure or misoperation of the dam will result in probable loss of human life.”

“Significant hazard” refers to a dam in which failure or misoperation would not result in loss of life, but “could cause major economic loss, disruption of lifeline facilities, or impact other concerns detrimental to the public’s health, safety or welfare.”

A dam’s classification determines the frequency of inspection. Visual inspections of high hazard dams are required every two years, significant hazard dams every five.

Low hazard dams are required to be inspected every five years to determine whether down-stream conditions have changed enough to warrant raising the hazard classification.

In addition to their hazard classification, dams may also be described as “unsafe” or “potentially unsafe,” depending on the actual physical condition of the dam. According to DEM’s 2018 annual report on the dam safety program:

 

“At each inspection, the condition of the major components of the dam—the spillway, lower level outlet, and the embankment—are subjectively rated as good, fair, poor, or unsafe.

Good is defined as meeting minimum guidelines, where no irregularities are observed and the component appears to be maintained properly.

Fair is defined as a component that requires maintenance.

Poor is defined as one or more components that has deteriorated beyond a maintenance issue and requires repair.

Unsafe means the condition of a dam creates an unreasonable risk of failure that will result in a probable loss of life or major economic loss. Unsafe characteristics include: excessive vegetation preventing an adequate visual inspection, excessive seepage, erosion problems, inadequate spillway capacity, inadequate capacity and/or condition of control structure(s) or serious structural deficiencies, including movement of the structure or major cracking.”

Ten state-owned and dozens of privately owned dams are officially “unsafe.” Towns are required by statute to create emergency action plans for high and significant hazard dams, at the dam owner’s expense. A number of towns have not yet done so. Most dams in Rhode Island have not been reclassified in nearly two decades. A dam classified as low hazard 20 years ago might now actually be rated as high hazard.

“Many areas of the state have experienced significant growth in the same areas that would flood if a dam fails. The potential for downstream destruction and loss of life has increased quite a bit,” says Paul Guglielmino, the principal civil engineer of DEM’s dam safety program.

“Our biggest concern right now is to restore the high hazard dams to the condition in which they were originally built. That’s been the push since 2007, and we feel we’re making some good progress.”

 

WHO OWNS THIS DAM ANYWAY? 

About 35% of the high and significant hazard dams are privately owned. Repairing these dams can cost in the hundreds of thousands of dollars, well beyond the means of most private owners. “Because it means significant money,” says Guglielmino, “many of the private dam owners aren’t willing to be compliant and they choose to go to court. The only recourse they have is to fight us.”

In 2018, DEM pursued enforcement actions against 60 unsafe dams. Since then, only three have been brought into compliance. No enforcement actions have been issued against 32 of those dams because DEM has had no success yet determining actual ownership of the dams. For high and significant hazard dams determined to be unsafe, this poses a risk to Rhode Islanders statewide.

Without clear ownership, these unsafe conditions will persist and pose further threat to Rhode Island cities and towns. DEM is, given its limited resources, pushing forward as best it can in an attempt to identify the owners of the many private dams across the state, says Guglielmino.

“We’ve hired title attorneys as well as some engineers to help us find out who owns these structures and then help repair them. Some, when informed, didn’t even know they owned a dam.”

DEM also participated in a multi-agency informal working group on dam safety, and that group, with funding from the Rhode Island Office of Housing and Community Development, commissioned a study of Rhode Island dam owner liability in light of climate change. Read Porter, senior staff attorney in the Marine Affairs Institute at the Roger Williams University School of Law and the Rhode Island Sea Grant Legal Program, who led the study, says, “My hope is that DEM can bring this info to bear when they’re talking to private dam owners. The fact that people can be liable if something bad happens, even if they didn’t realize it was their responsibility, can really impress upon them the urgency of the issue.”

“But there it was. Thirty million gallons of water through the streets of town.”

A DAM SHAME

Built for flood control, water supply, hydropower, recreation, or even grist mills, the state’s dams are, on average, over a century old.

The waterbodies created by many of these dams provide crucial benefits to Rhode Islanders, from drinking water and flood safety to recreational opportunities and scenic beauty.

These benefits enhance the quality of life for many Rhode Islanders and also provide valuable wetland habitats—both upstream and downstream—for a vast variety of animal and plant species.

Yet while they are critical structures, they have, in so many cases, not been properly maintained. Some are no longer adequate to handle the intense rainfall and floods of a changing climate. Yet they are being relied upon to protect more and more people as housing developments spring up nearby.

The failure in 1998 of California Jim’s Dam in South Kingstown, classified at the time as a low-hazard dam, was a wake-up call for dam safety statewide.

“I remember it very well,” says Jon Schock, environmental engineer in South Kingstown’s public works department. “We received a call from someone in town saying there was water coming down Kingstown Road (a main thoroughfare). I didn’t think it was possible. Hadn’t happened before in my experience. But there it was. Thirty million gallons of water through the streets of town.”

The South Kingstown dam featured a low-level outlet, but debris had accumulated and stopped the flow of water. Water found its way around the outlet pipe and began eroding the dam itself. The breach happened below and around the dam, not over the top of it.

“These dams are not as influenced by the amount of water as they are by development,” says Schock.

“What we see is, when these dams were built at the turn of the century, demographics were different.  Today, there’s much more building, and more impervious surface. In the old days, a lot of rainwater would infiltrate the ground and there was little danger of dam breach. Today, the scenario is very different.”

In 2010, as a record rainfall fell throughout Rhode Island, the Blue Pond Dam in Hopkinton collapsed, sending 179 million gallons of water rushing through Hopkinton, Richmond, and eventually Westerly.

DEM had expressed concern about the century-old, privately owned dam following an inspection and subsequent written warning in 2008. Talks between DEM and the dam’s owner were in progress but didn’t move fast enough. The 2010 storm proved formidable. Water over-topped the dam and destroyed it, along with a handful of surrounding roads and bridges. It was one of five dams that failed in Rhode Island during the storm. Since that event, DEM has taken ownership of the dam, including 67 acres around it, and converted it into a wildlife management area. The structure has not been rebuilt.

 

A CHANGING CLIMATE

Perhaps what environmental lawmakers and dam safety groups fear most is a changing climate.

“There’s just a lot more rain in our rainstorms,” says Porter.

He and his students studied the liability associated with dam owners, how that liability compares to other states, and what impact climate change will have on these dams and their owners.

“The two biggest problems in this area,” he says, “are changing patterns of land use and a large increase in precipitation due to climate change.”

“The increased amount of water in our rainstorms will really be challenging our dams,” Porter says. “It will provide a test to see how much water they can truly hold back. Are legacy dams, dams that were constructed in 1830, adequately designed to contain today’s storm-water? I think we know the answer to that, and that’s worrisome.”

“It’s a very hot topic right now,” admits Pinto. “We talk about it a lot. Unfortunately, we don’t live in a perfect world, which would allow us to address the issue and handle all of the other significant issues we’re dealing with at the same time. We just don’t have the bodies.”

On average, Rhode Island sees a foot more rain annually than it did a century ago due to the changing climate. Sea levels have risen a total of 8 inches (measured in Newport) since 1930.

The new normal in terms of water volume makes these dams highly susceptible to flood.

“We worry very much about the reality of climate change,” says Porter. “Newer, more modern dams are built for a pre-determined maximum flow. But so many of these legacy dams just aren’t built to handle the kind of conditions we’ll likely be seeing in the not-too-distant future. If you don’t account for climate change in precipitation and you’re getting a lot more rain, you could lose your entire dam. Nature is changing things, humans are changing things, and the dams and the dam owners are sitting in the middle.”

BACK TO SCHOOLS

Restoring fish populations to the Pawtuxet River

FOR 200 YEARS OR LONGER, DAMS HAVE BLOCKED A NUMBER OF IMPORTANT SPECIES of anadromous fish from completing their lifecycle.

Alewife, blueback herring, and American shad are just a few of the anadromous species that live their adult life in saltwater but return to freshwater to spawn and whose populations had virtually disappeared from the Pawtuxet River watershed following the Industrial Revolution.

“If you put a dam in a flowing body of water, you can use water to power America,” says Robert Nero, chairman of the Pawtuxet River Authority.

“That’s what Samuel Slater did, and the Brown family in the late 1700s. They copied what they saw in England at the time of the original industrialization of this country and began using hydropower to run looms. Dams started popping up all around the state.”

In Pawtucket, where Slater built his company, Rhode Island rivers were teeming with Atlantic salmon. Once the dams were built, that population, and many other indigenous species, disappeared.

“They just died out here,” says Nero. “They couldn’t make it back to their spawning grounds. You can be certain that most of the rivers in New England that empty in the ocean … every one had major fish populations for thousands
of years until the Industrial Revolution.”

The smaller freshwater fish were foraging for larger saltwater fish and other animals, so when that important food source disappeared, so did the species feeding on them. The entire ecosystem changed as the dams were constructed. Ruing the absence of fish and wildlife in the area, Nero had a vision. Inspired by the progress made restoring fish populations in the Wood and Pawcatuck rivers, he set his sights on doing the same for the Pawtuxet, where a 250-year-old dam at the foot of Pawtuxet Village obstructed anadromous migration patterns.

“We just wanted to return the river to what it naturally was,” says Nero. “We wanted to restore these fish populations to the Pawtuxet. But in order to do so, we had to remove the dam.”

At DEM, dam removal is the last option. But Nero, working with fish and wildlife experts, demonstrated that removal, in this case, was for the greater good.

In the culmination of a nine-year effort, Nero oversaw the deconstruction of the 150-foot Pawtuxet Falls dam in 2011. The $600,000 project, which involved DEM, the Pawtuxet River Authority, the Narragansett Bay Estuary Program, and other partners, removed the center section of the dam, enabling water to flow freely over the natural bedrock falls for the first time in over two centuries.

Since then, the river has come beautifully back to life, restoring vital connectivity between Narragansett Bay and the streams and ponds of the Pawtuxet. Massive migration is underway once again, with schools of herring and shad now able to reach their spawning grounds.

“It’s amazing to see these species return to the area,” says Nero. “We took their freshwater pathway from them, and now we’re returning it to them.”

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