Hydroseeding for Transportation Projects
Hydroseeding has connections with most forms of transportation, including revegetation around highways, airports, and mass transit projects. It is even a part of water-related travel, if one considers work done on the grounds at marinas, shipping channels, and ports.
Working on the Railroad
One recent transportation-related hydroseeding project was for BNSF. That acronym might not be familiar to most people, but if you guessed it is related to railroads, you’re on the right track. BNSF stands for Burlington, Northern, Santa Fe, and Frisco Railroad.
BNSF’s freight trains—1,600 on an average day—crisscross a great section of the western and northern US. Its four-part, full name is derived from more than 400 different railroads that merged and remerged into one, now the second-largest freight rail network in the US.
Those 400 separate railroads had names that sang with regional notes and celebrated the part their trains played in building this country. The names that contributed to the formation of BNSF are pure Americana: Chicago, Burlington and Quincy; Great Northern (remember its red emblem with the white mountain goat?); Spokane, Portland, and Seattle; and Frisco. Other regional railroads that became a part of BNSF include the Denver and Rio Grande, the Northern Pacific and the Atchison, and Topeka and Santa Fe (the latter celebrated in song by Judy Garland in the film Meet Me in St. Louis).
The modern BNSF Railroad’s freight trains carry steel, coal, lumber, grain, new cars, and more, through 28 states and three Canadian provinces. Within BNSF’s territory is the state of North Dakota.
When the railroad needed to have major construction work done on some of its tracks in North Dakota, hydroseeding was an essential part of the project. Sherbrooke Turf of Pelican Rapids, MN, performed this hydroseeding work.
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The job involved establishing vegetation beside approximately 120 miles of railroad tracks. The project extended from west of Minot, ND, to Snowden, MT, a town just over the border between the two states.
Credit: SHERBROOKE TURF
More than 500 acres needed hydroseeding.
Actual acreage hydroseeded totaled more than 500. Some sections were done more than once, because of weather or disruption by construction equipment. Rights of way, construction limits, and borrow areas were hydroseeded.
“Sometimes we worked on both sides of the tracks, sometimes just on the north side, and sometimes just on the south side,” says David Sherbrooke, owner of Sherbrooke Turf, who got started in hydroseeding at the age of 13, helping his dad.
The seed used on the project was a North Dakota Department of Transportation–approved mix. It included fescue and a nurse crop of oats and rye. Soil amendments were not needed, but a triple blend fertilizer was included in the mix.
Hydro-Blanket by Profile Products of Buffalo Grove, IL, was included in the hydroseeding mix. This bonded fiber matrix (BFM) sprays on as mulch, but dries to form a breathable blanket that bonds more completely with the soil. It includes strong tackifiers.
Other products used on particular project sections included Soil Guard, a BFM from Mat Inc. of Floodwood, MN, and Second Nature Spray Mat from Central Fiber of Wellsville, KS. All three products were applied at 3,900 pounds per acre.
Adding green dye to the hydroseeding mixture before it is sprayed is a common practice. This tracer makes it easy for crew members to see which areas have been seeded and which ones have not yet been worked on. However, because BNSF’s signature color is orange, Sherbrooke decided to use this color instead of the usual green for the tracer.
“Profile worked with us to get it just right,” he says.
Sherbrooke’s crews used HydroSeeders from Finn Corp. of Fairfield, OH. The model of choice was the T330.
Blankets 16 feet wide (ET-X2 Great Lakes aspen fiber from Erosion Tech of Juliette, GA) were placed along every ditch bottom. Straw wattles (12-inch bio-logs from Flaxtech of Rocklake, ND) were installed every 100 feet.
Sherbrooke says the project’s main challenge was “scheduling work in different locations [to mesh with the general contractor’s work]. We would be at one end of the project one day, and have to be at the other end [many miles away] the next day.”
He adds that the weather was not very good during much of the project. “There it’s either rainy or very dry.”
The main contractor for this project was Ames Construction of Burnside, MN. Work on the project, done in sections, began in fall 2013 and ended in fall 2015.
Profile Products distributor Ramy Turf Products of Mankato, MN, was awarded one of two 2015 Project of the Year Awards by Profile Products for the firm’s work with Sherbrooke on the BNSF project.
“We use a lot of Profile Products,” says Sherbrooke.
Interstate 15 is the major thoroughfare from Los Angeles, CA, to Las Vegas, NV, running north and east. Repair of the Devore Interchange—where I-15 and I-215 intersect in San Bernardino County (about 15 miles north of the city of San Bernardino)—was a major southern California road construction project.
“It was a design-build. We were subcontracted to Atkinson Construction on this $500 to $600 million project,” says John Richards, co-owner of Pacific Restoration Group (PRG) in Perris, CA, about 70 miles east of Los Angeles.
The project had two main challenges for the PRG hydroseeding crews. First, parts of the road are in areas of high winds. When those winds blew strongly, it was too windy for any seeding.
Second, the roads around the interchange carry so much traffic that lane closures could be done only for short intervals of time. The traffic was heaviest where people were traveling to and from Las Vegas.
“Coordinating the work while only one lane was closed was difficult. We [often] had a short window of time to work in,” explains Richards.
He adds, “A lot of the work had to be done at night. We had lights on the HydroSeeders and light stands that highway work crews use. The city put them up for us.”
Hydroseeding totaled about 100 acres, and the work was scattered.
“We did three to four acres at a time, as the contractor was ready for us. They paid us extra to reseed some areas that were disturbed by final construction. Slopes were mostly two-to-one or flatter,” says Richards.
Of weather during the project, he says, “The wind with the [ongoing] drought was a factor. We had no erosion problems because we had no rain.”
This Caltrans (California Department of Transportation) project required not only native seed mixes—five different ones for the different areas and microclimates—but also native seed collected from the sites. For this specialized seed, PRG relied on S & S Seeds of Carpinteria, CA.
“Since 1993 when we started in business, we’ve ordered seed almost exclusively from S & S,” says Richards.
The five different mixes each contained seeds for eight to 15 different species of native plants, collected on or adjacent to the work areas. Plantago, also known as California plantain, was included as a nurse crop.
“We used barley and rye as nurse crops years ago, but we’re not allowed to anymore because they are not native plants,” notes Richards.
Soil in the work areas was mostly alluvial, rocky, and gravely. The hydroseeding mix did not contain amendments, but mycorrhizal inoculum, a fungus that occurs in soil naturally, was added to help the vegetation develop stronger roots.
“It gives the native plants a head start to outcompete the weeds,” explains Richards.
The main work areas were not watered. PRG added some native trees and shrubs as mitigation for trees that had been taken out. These plants were watered. They would grow to screen the road from nearby homes.
For hydroseeding work, PRG has four HydroSeeders from Finn Corp. Their models are three T330 Titans andone T400 Titan.
PRG’s supplier, S & S Seeds is known for providing its customers with custom seed mixes. Seeds are chosen to produce plants that will thrive with a particular site’s soil type, climate, and amount of moisture, with consideration for appearance and aesthetics.
S & S Seeds offers customers an additional service that not every seed company can. If the job specifications require that the hydroseeding company use not just native seed, but native seed collected from the site, S & S can be sure that this requirement is met.
“We’ve always done site-specific collection,” says Jody Miller, site collection manager for S & S Seeds.
Site-specific seed collection is performed by people who have the training to identify native plant species and know where harvestable plants grow in the area. Miller says that S & S has lots of contracts with private landowners, state parks, nature conservancies, and other places for seed collection.
If the customer wishes, S & S Seeds will send seed samples to an independent lab for verification of purity and germination rate. S & S schedules harvesting dates to collect as many seeds of peak quality as possible.
After the native seeds are carefully collected from the appropriate site, they are dried properly, cleaned, and conditioned. They are stored safely in the S & S Seeds warehouse, even for the long term if necessary.
Miller says S & S collects seeds from April (sometimes March) until as late as November, depending on weather. The majority of customers who need site-specific seed collection are private, such as residential developers and energy companies.
Offering site-specific seeds is “always challenging, because you’re limited to that site and dependent on each season’s conditions. What’s growing there and what’s been disturbed before we get there [affect the seeds that can be obtained],” she explains.
Credit: HIGH COUNTRY HYDROSEEDING
Asheville Regional Airport removed and replaced a worn-out runway.
Asheville’s location in the mountains of western North Carolina has made it famous as a vacation destination. The city and surrounding area are attracting an increasing number of both visitors and new residents.
“Asheville is a unique place, and in the last 10 to 15 years it has experienced a huge boom,” says Allen Stewart, owner of High Country Hydroseeding of nearby Canton, NC.
Stewart’s company was chosen to do hydroseeding on a major construction project at the Asheville Regional Airport. This airport project was appropriately named SOAR, which stands for Significant Opportunities for Ashville and the Region.
SOAR includes replacing Asheville Regional Airport’s old worn-out runway with a new one. The FAA says that the airport needs only one runway. To keep the airport operating during the years of construction, the first phase of the project involved building a temporary runway, which serves as the main runway, while the old runway is removed and the new one is being built. When the project is finished in 2018, that temporary runway will have been converted into a second taxiway, and there will be more room between the taxiways and the new runway.
Work on the project’s second phase (removal of the 8,000 linear feet of old runway) began in July 2016 with installation of silt fence around the entire section. Stewart’s supplier for the silt fence and other erosion control materials is Pioneer Seed and Supply in Waynesville, NC.
Grass seed for the hydroseeding mix was a blend of tall fescue, Kentucky bluegrass, and hard fescue. The supplier, Tri Star Seed Company in Knoxville, TN, ships the premixed seed in 50-pound bags to Stewart’s company.
For nurse seed Stewart includes “a little bit of millet. It works well in our hot, dry climate.” He also uses rye. “Millet dies out when frost comes, and rye seeded in spring dies when hot weather comes.”
The grassy areas around the runway, taxiways, and airport buildings will be mowed. The slopes will not be mowed, so lespedeza was added to the regular seed as a ground cover. Excelsior erosion control blankets from East Coast Erosion Control of Bernville, PA, were installed on the slopes.
Credit: EROSION CONTROL SERVICES
Stewart says that about 25 of the 175 acres are sloped, “mostly two to one. The slopes range from 20 feet up to 120 feet—we’re in the mountains.”
On flat areas at the airport, High Country Hydroseeding is using its Bowie hydroseeding machines (made by Bowie Industries in Bowie, TX) to spray fertilizer and hydromulch to cover the seed. The seed is first planted with a tractor.
“The reason we’re using a tractor for seeding—planting like a farmer does, so the seed is put into the ground, not broadcast—is that the airport requested it for better results. It’s very windy there, and the surface is so dry,” explains Stewart.
Soil amendments include 500 pounds of fertilizer (10-20-20) per acre. Conwed Fibers Hydro Mulch from Profile Products and two tons of lime are also added to the mixture.
“For all of this area, the North Carolina DOT requires four thousand pounds of lime per acre to correct the pH of the soil,” explains Stewart. On jobs that need this much lime, he notes, “When we start spraying, we continue. If we have to stop for any reason we have to flush the pump and tank with clear water so the lime doesn’t set up [inside the machine].”
Credit: EROSION CONTROL SERVICES
On most of the company’s big projects, he says, “we blow straw and tack it. Obviously straw is not friendly to jet engines, so this project wouldn’t allow any straw.”
Stewart says the two biggest challenges of the project so far have been “the size and the weather.” Summer temperatures 10 degrees above normal and no rain in June required the crew to use dust control equipment to water the ground. However, “by the end of July we had so much rainfall that we couldn’t get compaction,” he says.
One July day brought 2 inches of rain in a little more than 30 minutes. “I’ve been doing this work for 18 years. There’s no BMP that can be installed that can handle that type of rain event, in that short a time,” he says.
North Carolina requires any ground that is disturbed to be reseeded. That policy makes for a long work year for High Country’s nine employees and other hydroseeding companies there.
Credit: EROSION CONTROL SERVICES
Hydroseeding was needed on medians, shoulders, ponds, and borrow areas.
“We seed 12 months a year. Most years, we can get a couple of good weeks to work in December. January and February aren’t as good, weatherwise. We average 3,000 feet in altitude, but not a lot of snow. We have some 1-inch storms, some icy conditions,” says Stewart.
For all of their hydroseeding work, Stewart and his crew rely on Bowie hydroseeding machines. The company has five Bowie machines, from largest to smallest models.
“Mostly we use the Bowie Hydro-Mulcher Imperial 3000, their largest. This is the machine of choice for North Carolina DOT work,” says Stewart. “Bowies come with the big centrifugal pump that can handle a lot of DOT-required lime.”
Erosion Control Services of Virginia Beach, VA, performed hydroseeding work on Dominion Boulevard. This major road and bridge project in Chesapeake, VA, was done for the city of Chesapeake.
Work on the $212 million project began in the spring of 2013. It was finished at the end of 2016. The project’s prime contractor was E.V. Williams Inc. of Virginia Beach.
“They’ve gone above and beyond in providing us with enough manpower and traffic control to help us get the work done efficiently and safely,” says Justin Munden, co-owner with Jeremy Hedrick of Erosion Control Services. That support was important, Munden says, because the project’s biggest challenge was “dealing with traffic and working on an active road.”
Munden says that the hydroseeding work on the project covered “about 70 acres—shoulders on both sides of the road, medians, around ponds, and borrow excavation areas.”
The grass seed was standard tall fescue and Bermuda grass blend. The wildflower seed was a nonstandard upland mix and a wetland seed mix. The wetland seed mix was used for mitigation purposes. The new wetlands area would offset wetland impacted by the construction.
Regular seed totaled 13,084 pounds and overseeding took another 8,177 pounds. They were applied at the rate of 170 pounds per acre. Rye and millet (6,272 pounds) were used as temporary seed. Landscape Supply Inc. of Roanoke, VA, supplied seed.
The project site’s soil is sandy and loam. It was amended by the addition of 260 tons of lime, and three tons of fertilizer (15-30-15).
EC2 single mat straw blankets (also from Landscape Supply) were applied to protect the seed. Flexterra, a high-performance flexible growth medium from Profile Product, was used for the same reason on the slopes of ditches and on some shoulders.
Along waterways, where temporary seeding was done, the hydroseeding crews applied 150 bales of wheat straw. Also called straw mulch, this material was blown on using a B260 model straw blower from Finn Corp. Munden likes the B260’s ability to place straw at a distance. “You can get farther than 100 feet,” he says.
In areas of water, more than 1,500 feet of turbidity curtains were installed to preserve water quality during construction. The Tough Guy turbidity curtains used are made by Aer-Flo of Sebastian, FL.
For the Dominion Boulevard project, the Erosion Control Services crews relied on two T330 Finn HydroSeeders, which are mounted on two Mack trucks.
“The sheer volume these Finn 330s are able to pump out makes it hard to fall behind,” says Munden. “They are amazing in their ability to do such a large volume of seeding. We can get 16, 18, even 20 acres a day done if we have two crews out. With their reliability we do not have issues that cause us to fall behind.”
Munden recalls an airport project where Erosion Control Services was not the original hydroseeding company. One runway was shut down for the weekend only. It would have to reopen to air traffic on Monday.
“We were able to hydroseed 32 acres over the weekend to prevent a logjam for a good contractor. With a Finn 330 you get serious production,” he says.
Munden says that he and Hedrick both had backgrounds in commercial construction sales and wanted to go into business together. “We saw that erosion control was not going away, with regulations tightening. Keeping erosion from happening and keeping silt in its place would continue to be work in demand.”
Munden and Hedrick started working together in 2007, installing silt fence on construction sites. When a contractor asked them about doing hydroseeding a year later, they knew that Hedrick had enough previous experience to get them started.
Munden and Hedrick bought their first Finn HydroSeeder, the company’s smallest model, a T60. That purchase launched them into hydroseeding work and made them loyal fans of Finn’s machines.
“Our first big job was a 56-acre landfill cap, done in 2009. We seeded 41 acres with wildflowers,” recalls Munden. “In 2011 we added our first T330 HydroSeeder. In 2013 we added a second one.”
Air, road, and rail travelers and shippers likely never associate transportation with hydroseeding. But contractors and owners know that properly done hydroseeding is essential for environmentally compliant transportation projects.