Boom: Oregon DOT Uses ‘Fireworks’ to Drive Birds from Bridges

The Oregon Department of Transportation has a public outreach message for water birds who want to nest on two of their iconic bridges: Beat it.

[Above: Matt Alex, a wildlife biologist with the U.S. Dept. of Agriculture, fires a “flash pistol” to scare off birds. Photo via the Oregon DOT.]

Officially, Oregon DOT is utilizing an auditory dispersal method to relocate cormorants to facilitate infrastructure maintenance, such as inspection and painting. In practice, a technician fires a pistol that flashes, pops, and whistles. The sounds and lights chase the birds from the bridges.

“It basically is a gun-like mechanism that looks like a fireworks show,” explained Angela Beers Seydel, an Oregon DOT public information officer, in describing a test of the procedure in early March. “It whizzed, it banged, it flashed.”

Both bridges are on U.S. 101, along the Pacific coast. The 4.1-mile Astoria-Megler Bridge crosses the Columbia River and connects Oregon and Washington. It is the longest continuous truss bridge in the U.S., and painting it takes more than eight years and about $75 million.

Meanwhile, the Yaquina Bay Bridge – located about 300 miles south – is an 88-year-old arch structure built by the Public Works Administration; a depression-era federal program that also financed the Lincoln Tunnel and Hoover Dam. Conde McCullough, a renowned Oregon DOT engineer (he has his own Wikipedia page) designed the Yaquina Bay Bridge – along with 14 others along U.S. 101.

The sound-and-light program will continue through September on the Astoria-Megler Bridge and through June on the Yaquina Bay Bridge.

“These birds affect our ability to conduct inspections,” noted Don Hamilton, an Oregon DOT spokesperson. He added that those inspections occur at least every two years, but that cannot happen if birds, bird nests, or bird “guano” are on the bridge. Guano, or bird droppings, also have a corrosive effect on bridges and can be toxic to humans.

One or two technicians go on the U.S. 101 bridges every day and fire off several rounds.

Seydel said the sensory assaults take place at random times “so the birds don’t recognize a pattern. You want them to be uncomfortable to be in that area.”

Recently, Oregon DOT used propane cannons, which produce louder and deeper sounds, to successfully chase away birds from the Interstate 5 bridge over the Columbia River. Seydel said Oregon DOT might bring out those “big guns” if the pistol sounds and flashes do not work on the U.S. 101 bridges.

“There’s also the canon, if necessary,” she said. “So, whiz, bang, boom is the possibility.”

Tennessee DOT Helping Deploy ‘Seabins’ for River Cleanup

The Tennessee Department of Transportation has teamed up with Keep the Tennessee River Beautiful (KTRB) and other partners to establish a network of 17 “Seabin” automated litter and debris removal devices across the Tennessee River watershed.

[Above photo by the Seabin Project]

Seabin devices work continuously to skim and collect marine debris from the surface of the water. Each receptacle can remove up to 3,000 pounds of marine debris annually, while also filtering out gasoline, oils, and “micro-plastics” from the water.

Grants from the Tennessee DOT and the national Keep America Beautiful organization provided the funds supporting this deployment of the Seabin devices.

The Tennessee DOT’s contribution includes the purchase and installation of 10 devices at locations throughout Tennessee, as well as funding for two years of water-based cleanups of the river and its tributaries within the state – funding made in conjunction with the agency’s “Nobody Trashes Tennessee” litter prevention campaign.

“[Our] partnership with Keep the Tennessee River Beautiful demonstrates the link between roadside litter and debris that ends up in our waterways,” explained Joseph Galbato, Tennessee DOT interim commissioner, in a statement. “Investing in this substantial network of litter removal devices is another example of how TDOT promotes innovative solutions to making our state cleaner and keeping our waterways clear.”

In addition to the 17 Seabins deployed in Tennessee, another two will deploy on the Tennessee River in Alabama, with one other placed on one of the river’s tributaries in North Carolina.

“Until now, all of our work has only been able to prevent micro-plastics in our waterways, so we are thrilled to the Tennessee DOT and Keep America Beautiful for these – as I see it – revolutionary grants and to our partners who will be maintaining the Seabins to make this trailblazing project possible,” added Kathleen Gibi, KTRB’s executive director.

The Tennessee DOT is an agency known for funding different and innovative ways to reduce littering.

For example, in April 2021, the agency helped fund a pair of new exhibits at the Tennessee Aquarium illustrate how micro-plastics and other roadside trash can negatively affect the health of the ocean as well as rivers, lakes, and streams.

The new exhibits – housed in the Aquarium’s “River Journey” and supporting the Tennessee DOT’s “Nobody Trashes Tennessee” litter reduction campaign – include actual debris taken from the banks of the Tennessee River: the focus of its current Seabin deployment project.

‘Canopy Clearing’ Helping Improve Roadway Safety

Since November, maintenance crews with the West Virginia Division of Highways – part of the West Virginia Department of Transportation – have cleared more than 170 acres of trees and branches overhanging more than 500 miles of state roadways: enough trees and branches to fill up about 170 football fields.

[Above photo by the West Virginia DOT]

Called “canopy clearing,” that process is critical to improving roadway safety. According to the “Vegetation Control for Safety” manual published by the Federal Highway Safety Administration, trees growing close to a roadway can present a “fixed object hazard” to travelers, including motorists, bicyclists, and others. Grass, weeds, brush, and tree limbs can also obscure or limit views of traffic control devices –such as signs or stoplights –as well as approaching vehicles, wildlife and livestock, pedestrians, and bicycles. Thus, controlling vegetation helps reduce crashes and injuries, FHWA noted.

“Canopy clearing” adds another element for improving roadway safety, the agency noted. When trees and shrubs – particularly evergreens – in the right-of-way cast shadows on the pavement, freeze-thaw cycles may create isolated ice patches on the pavement – easily causing loss-of-control crashes. Thus “canopy clearing” or “daylighting” by cutting taller vegetation lets the sun help with thawing and ice control, while also generally helping preserve pavements by preventing the buildup of moisture on roadways during warmer months.

In the past, the West Virginia Division of Highways noted in a statement it could only remove 140 acres of the canopy a year, or 14 acres for each of the state’s 10 highway districts. However, the state lifted that restriction in 2022, allowing districts to cut more trees in between winter snows.

The agency added that, by law, its crews can only clear canopy between November 15 and March 31; a restriction designed to protect endangered bat populations, which do not typically use trees during that time span.

State departments of transportation are also working to expand their knowledge base regarding the impact of trees and shrubbery on roadway safety and pavement longevity.

For example, a 95-page research paper compiled for the Ohio Department of Transportation five years ago by Ohio University suggested designs for a “decision-making tool or process” to assist the agency with tree canopy maintenance practices, assessing the impact of trees and tree species on pavement degradation, road condition, and road safety in climatic conditions typical of Ohio.

NCDOT Providing Material for Artificial Reefs

The North Carolina Department of Transportation is providing more than 1,000 tons of damaged concrete pipe to help the North Carolina Division of Marine Fisheries shore up two artificial reefs.

[Above photo by NCDOT]

NCDOT sent those discarded culverts – which accumulated over the past several years as the result of an aggressive pipe replacement program in part due to damage caused by recent hurricanes – to the Port of Wilmington for eventual deployment off of the Brunswick County coast.

N.C. Division of Marine Fisheries – part of the North Carolina Department of Environmental Quality – maintains several artificial reefs that create habitat for fish and ideal fishing sites.

It said artificial reefs create habitat for fish by creating three-dimensional structures that replicate the ecological functions of food and refuge fish and other marine life need to survive and create “crucial” spawning and foraging habitat for many commercially and recreationally important fish species.   

The fisheries division has been working with NCDOT to find “new and cost-effective uses” for scrapped concrete pipe. Using that piping to build artificial reefs for marine life along the state’s coastline in a money saver, the agency noted – eliminating $65,000 in tipping fees to dispose of it in a construction and demolition landfill.

Ken Clark, an NCDOT district engineer, said the idea for donating the pipe arose during a conference for coastal resiliency. That is when he discovered the state’s marine fisheries division could repurpose his stockpile of precast concrete, barreled-shaped pipe to augment existing artificial reefs. 

“We had considered many options on how to properly dispose of this unusable material when we formed this unique collaboration with the Division of Marine Fisheries last year,” he explained in a statement. “This program mutually benefits both state agencies.”

Other state departments of transportation are involved in similar artificial reef construction projects.

For example, in 2020, the New York State Department of Transportation began helping expand a series of artificial reefs off the shores of Long Island as part of a three-year-long multiagency effort – dumping a retired tugboat, 16 rail cars, and a streel turbine on Hempstead Reef.

“[We are] proud to work with our sister agencies on this important program, repurposing transportation materials to expand artificial reefs and support biodiversity, fishing, and tourism,” explained Marie Therese Dominguez, NYSDOT’s commissioner, in a statement at the time.

“It is another example of how [our state] is taking bold steps to protect our ecosystems and foster sustainable economic growth that will benefit current and future generations of New Yorkers,” she said.

Maryland Works to Reduce Road Salt’s Environmental Impact

In conjunction with several state agencies, including the Maryland Department of Transportation, the Maryland Department of the Environment (MDE) is spearheading an effort to reduce the amount of salts entering rivers, streams, and groundwater while also ensuring roads remain safe for winter travel.

[Above photo by the Maryland DOT]

MDE has been working for several years with state agencies and local jurisdictions on new salt application strategies, including use of improved weather forecasting, using the right amount of salt, targeting roads in most need of treatment, using brine to reduce overall salt usage, and increasing training for employees and contracted equipment operators.

The agency noted that Maryland DOT’s State Highway Administration (MDOT SHA) has used those and other strategies over the past five years to reduce its overall salt usage up to 50 percent.

MDOT SHA has moved to use salt brine – a liquid solution that is 22 percent salt and 78 percent water – before, during, and after winter weather events. Pre-treating roads with salt brine prevents the initial bonding of snow or ice, thus giving road crews time to mobilize. The agency now has two “tow plows” – separate plows towed behind a salt/plow truck to clear an additional travel lane – which enhance snow-clearing operations and reduce the need for road salting.

MDOT SHA has also designated salt brine-only routes for the duration of winter storms, resulting in less overall salt use when compared to routes where only rock salt is used. The agency pre-wets rock salt with salt brine to reduce the “bounce and scatter” effect of salt solids ricocheting off the highway.

MDOT SHA also works with weather forecasters to develop a treatment plan and employs more than 100 mobile infrared sensors at key locations, along with mobile sensors, to determine conditions and target its storm deployment – greatly contributing to salt reduction efforts.
“[We] congratulate and thank the Maryland Department of Transportation for leading by example when it comes to reducing the use of road salts that can threaten public health and our environment,” said Ben Grumbles, Maryland’s secretary of the environment, in a statement.

While sodium chloride or salt is effective, relatively inexpensive, readily available, and easily stored, it can destroy a soil’s structure and cause erosion, damage, and kill vegetation, while contributing to the corrosion of metal bridges and motor vehicles, MDE said. It can also seep into groundwater and runoff into surface waters, contaminating wildlife habitats and potentially affecting drinking water.

The agency noted it has increased monitoring for sodium chloride in the environment to gain information to help develop restoration plans. However, MDE noted that once salt has entered the environment there is no effective way to remove it. Thus, the best solution is a widespread, decreased use of road salt, it noted.

AASHTO Comments on Proposed Migratory Bird Permit Rule

The American Association of State Highway and Transportation Officials is “generally supportive” of a rule proposed in October by the U.S. Fish and Wildlife Service (USFWS) to develop a national migratory bird “incidental take mechanism” that also provides “flexibility” to state departments of transportation as construction seasons and bird breeding seasons vary across the country.

[Above photo of migratory swans by the U.S. Army Corps of Engineers]

The proposed rule regards the Migratory Bird Treaty Act of 1918, which protects migratory bird species between the United States and Canada. That law makes it unlawful without a waiver from the USFWS to “pursue, hunt, take, capture, kill, or sell” nearly 1,100 species of birds listed with the statute and does not discriminate between live or dead birds. It also grants full protection to any bird parts including feathers, eggs, and nests.

AASHTO stressed in a December 3 letter to the USFWS in a letter that it is desirable “to have a mechanism that allows state DOTs to propose bird management timeframes and best management practices” to limit migratory bird take.

AASHTO added that state DOTs do not support a general conservation fee as part of the transportation permitting process when migratory birds are involved. However, the organization noted that an “in-lieu fee approach” for individual transportation projects with unavoidable impacts could make sense depending on the details.

Colorado DOT Helping Reduce Impact of Firefighting Foam

The Colorado Department of Transportation’s Division of Aeronautics recently wrapped up a two-year effort to help certified commercial service airports statewide acquire equipment to minimize the environmental impact of aircraft firefighting foam containing toxic chemicals known as per- and polyfluoroalkyl substances or PFAS.

[Above photo by the Colorado DOT]

The Colorado Aeronautical Board, which oversees the Colorado DOT’s Division of Aeronautics, approved $400,000 in state aviation funding to assist with this equipment swap effort – only the second such program in the nation – in collaboration with state airports and the Colorado Department of Public Health and Environment.

This effort comes amid an increasing environmental focus on PFAS chemicals, which pose challenges to drinking water reserves.

For example, the Senate Committee on Environment and Public Works held a hearing in October to assess ongoing and proposed responses to the presence of PFAS chemicals in the environment, particularly in U.S. waters, by the Environmental Protection Agency.

Radhika Fox, the EPA’s assistant administrator for water, noted in her testimony at that hearing that a “growing body of scientific evidence” shows that exposure at certain levels to specific PFAS can adversely affect human and ecological health. Studies indicate that two common

PFAS – perfluorooctanoic acid and perfluorooctane sulfonate – can cause reproductive and developmental, liver and kidney, and immunological effects in laboratory animals. Both chemicals also caused tumors in animal studies, she said. Fox added that the most consistent findings from human epidemiology studies are increased cholesterol levels among exposed populations as well as some cases where that chemical family affected birth weights, the immune system, caused cancers, and thyroid hormone disruption.

Currently, commercial service airports certified under Federal Aviation Administration regulations are required to use PFAS-based foam and to annually test and certify aircraft rescue firefighting equipment and the foam utilized.

Under the provisions of this new statewide aviation initiative, however, the Colorado Division of Aeronautics said in a statement that it provided 100 percent funding for the acquisition of specialized testing and containment equipment designed to allow FAA-compliant firefighting foam testing to take place without the need for regular foam discharges. 

In total, 12 eligible airports participated in the division’s program, with the exception of Denver International Airport, as it already had the equipment, and Colorado Springs Airport, where the U.S. Air Force provides aircraft rescue and firefighting services.

Minnesota DOT Assisting with Bat Deterrence Research

The Minnesota Department of Transportation is helping test ultrasonic bat “deterrence devices” at two bridges to help keep the mammals away from such structures when they undergo maintenance and/or repair activity.

[Above photo by the Minnesota DOT]

The agency noted in a blog post that bats like to roost in bridge expansion joints and temporarily preventing such roosting during bridge maintenance repair activity typically requires installing physical barriers that are often difficult to establish effectively, due to the design characteristics of many structures.

More importantly, the Minnesota DOT does not necessarily want to keep bats away permanently from its bridges because bat populations throughout North America are in serious decline. For example, the agency said white-nose syndrome – a fungal disease – has killed more than 5.7 million bats in eastern North America since 2005. On top of that, wind turbines kill hundreds of thousands of bats in North America annually, according to a study by the U.S. Geological Survey.

The Minnesota DOT has worked with the Minnesota Department of Natural Resources and the U.S. Fish and Wildlife Service for the last two years testing battery-operated ultrasonic deterrence devices that reduce bat activity at bridge site when activated, but ensure a quick return of bat roosting activity when deactivated.

“This project was innovative. We worked with a technology that wasn’t really on the market yet for real-world applications in anticipation of its availability,” noted Christopher Smith, wildlife ecologist with the Minnesota DOT’s Office of Environmental Stewardship.

He added that current regulations require shorter maintenance period options during the construction season in order to protect bats – mandating that crews must avoid having bats present during their work, which impacts cleaning, painting, and other maintenance timelines.

“The presence of bats disrupts bridge work timelines and budgets, and work upsets habitation for species struggling to survive,” Smith said.

The Minnesota DOT noted that it hopes to develop a procedure for deploying this ultrasonic bat deterrence technology when needed and determine associated expenses from this two-year research effort.

Further study could consider the technology in different configurations and environments, test the devices at many bridges around the country, and conduct a cost-benefit analysis, the agency added – while also comparing the “relative impact” of acoustic deterrents on specific bat species.

Report Urges More Funding for Colorado DOT Wildlife Protection Projects

A state government report is calling for increased funding for transportation projects that protect big game habitats and corridors and prevent thousands of vehicle-wildlife crashes each year on Colorado’s roads.

[Above photo by the Colorado DOT]

The Colorado Department of Transportation and the Colorado Department of Natural Resources authored the Big Game Policy Report, subsequently released by Governor Jared Polis (D) on September 29.

A statement from the governor’s office said the report seeks to “prioritize state policy, coordination and investment to support our wildlife and ecosystems.”

The report notes that the effects of climate change, increased industrial, residential construction, plus ongoing infrastructure development increase the number of situations putting wildlife in conflict with people. The most glaring examples of such conflicts are the estimated 4,000 vehicle crashes with wildlife that cost an estimated $80 million each year in Colorado.

The Big Game Policy Report served as a follow-up to an executive order Gov. Polis issued in 2019 directing Colorado DOT to incorporate wildlife protection measures into “all levels of its planning process, to the greatest extent possible.”

The Colorado DOT already planned to make road improvements to U.S. 160 between Pagosa Springs and Durango when it decided to incorporate wildlife protection elements. The busy stretch of highway has been the scene of more than 350 big game-vehicle collisions in the last 10 years as drivers make their way to the Chimney Rock National Monuments.

The project, expected to wrap up this winter, now includes a wildlife overpass and underpass, high-deer fencing, and “jump out” ramps within the two-mile project area. The fencing helps “funnel” the moving herds toward the overpass or underpass, where they can safely cross the busy highway. The earthen ramps are inside the fencing and allow the animals to safely escape traffic.

By including wildlife elements into planned projects, “it gives us a bigger bang for our buck,” said Lisa Ann Schwantes, a Colorado DOT regional communications manager.

“We look at the projects already identified that need to be done, and we overlap them with wildlife projects and marry them together,” she said.

Though incorporating wildlife protection elements into existing planned projects can be cost-effective, the costs still add up. The U.S. 160 project has a total price tag of $12 million, $5.4 million of which include just the construction costs for the wildlife protection features.

The report points out that, while Colorado DOT continues to look for ways to protect big game and drivers from each other, the agency has no dedicated funding source for such wildlife projects – one reason why the new report calls on the state legislature to find new money to support such projects.

“While progress has been made, the General Assembly should prioritize new funding for transportation projects identified by CPW (Colorado Parks and Wildlife) and Colorado DOT that provide a clear benefit to wildlife populations and human health,” the report states.

Colorado DOT Helps Complete I-25 Wildlife Underpasses

The Colorado Department of Transportation and the Colorado Parks and Wildlife (CPW) agencies recently completed wildlife underpasses along a rural stretch of Interstate 25 between Colorado’s two largest cities, Denver and Colorado Springs.

[Above photo by the Colorado DOT]

This wildlife mitigation system is part of a $419 million transportation improvement project – known as the I-25 South Gap project – that aims to improve safety and travel on 18 miles of I-25 south of the Denver metropolitan region; a route that more than 87,000 motorists use on a daily basis.

The I-25 South Gap project’s wildlife mitigation system includes four new and one refurbished wildlife underpasses, 28 miles of deer fencing, and deer guards and jump-outs, Colorado DOT said.

Work on the underpasses is substantially complete with 8 percent of deer fencing installed – just in time to shepherd migrating wildlife safely under the interstate this fall. The I-25 South Gap project as a whole, however, should be finished by 2022, the agency noted.

The Colorado DOT and CPW are also now in the process of installing 59 cameras throughout the project’s wildlife mitigation system to help measure success.

Shoshana Lew, executive director of the Colorado DOT, said that these wildlife underpasses – used by bears, elk, and small game animals – are also some of the largest in North America.

“One of [our] core values is safety, and we are thrilled to deliver on this value to all who use I-25 in the area,” she explained in a statement.

“In Colorado, nearly 4,000 animal-vehicle crashes are reported annually, resulting in injuries and fatalities to people and costing an estimated $80 million,” Lew added. “In the I-25 South Gap, it is estimated that one animal-vehicle crash occurs per day. Our wildlife mitigation system aims to reduce these crashes by 90 percent.”

Photo by Colorado DOT

“Colorado DOT met with various agencies, including CPW, early in the planning process to come up with a collaborative solution,” noted Brandon Marette, land use coordinator for CPW’s Northeast Region. “Fast forward from our first collaboration meeting nearly five years ago to today, where wildlife is now using the underpasses that we planned together. There is more collaboration to come between our agencies as we continue to plan and implement strategies to keep both people and wildlife species safe, thus protecting what is unique to Colorado.”

State departments of transportation in various parts of the country have been working on ways to improve wildlife mitigation tactics over the past several years.

In 2019, the Pew Trusts issued a report that highlighted the work states are doing to boost safe passage for wildlife around roadways, while at the same time improving motorist safety.

“Big-game animals in the American West today are increasingly squeezed by growing suburban areas, energy development, climate change, and an expanding road network,” noted Matt Skroch, a manager with the Pew Charitable Trusts’ U.S. public lands and rivers conservation team and author of the report, at the time.

“[Those] factors are threatening the landscape connections that wildlife needs to move to and from their seasonal feeding and breeding grounds,” he added. “To conserve wildlife corridors while reducing wildlife-vehicle collisions in the West, state and local governments need to take the lead on these issues and guide their agencies to effectively link science with policy. Fortunately, this is beginning to happen. From Montana to New Mexico, states are identifying hot spots where collisions occur and linking those areas with the larger habitat conservation needs on either side of the road.”

For example, in April, the construction of the new Rock Creek Bridge to replace a culvert on US-20 recently won an engineering excellence award from the American Civil Engineers Council of Idaho – an award shared by the Idaho Transportation Department (ITD) and Jacobs Engineering. That new bridge now allows wildlife to pass under the highway, reducing the risk of possible collisions involving wildlife and vehicles on the roadway.

The ITD added in a statement that this particular section of US-20 witnessed 64 vehicle-wildlife collisions over the last five years, which totals a “societal cost” of approximately $2 million when adding together the cost of vehicle repair or replacement, medical bills, and increased insurance rates – not to mention the cost to wildlife.