Northern California’s Alameda County, the city of Livermore, and the California Department of Transportation have teamed up to work on a series of improvements on a 4.6-mile stretch of State Route 84.
“It’s a widening of Highway 84 beginning about 1 mile south of Interstate 580,” explains Bob Brown, president of Team EES Inc. of Alameda, CA. The project continues south from there, with the northern stretch of this roadway being upgraded first, beginning in the summer of 2012. The goal is to reduce congestion on this and on nearby highways.
“As far as drain inlet protection is concerned, on this particular project, there are 55 drain inlets that need to be protected,” Brown says. “The products that we always try to use, because they’re so superior to anything else out there on the market, are the products that are manufactured by ERTEC Environmental Systems. As far as I’m concerned, I’m not sure why all subcontractors aren’t using them. Maybe I should be happy they’re not, because that would make for more competition for me.
“They have four different kinds of guards,” he continues. “They have a Curb Inlet Guard, which we don’t have a lot of experience with yet, because the projects we’ve worked on just don’t have that many of that kind of inlet. It’s basically for the inlet in the curb itself. Then there’s a Combo Guard that protects both the curb and a combination of a curb inlet and a street inlet over a grate.
“Then there are the Drop Guards, which are most often elevated during construction projects. They’re elevated because they’re put in at a level where they need to be with the finished product. So they may actually be above the ground or above the soil at a certain point in time. This is one that we certainly installed on this project.
“Then there are GR-8 Guards, of varying sizes, that we buy from ERTEC, and these are just for the grates themselves. As far as the grates that we installed on this particular project, everything has gone very, very well. We, as the installers, love it of course, because they’re so much simpler than many of the other alternatives.”
He notes that other types of inlet protectors often involve inserts and filter fabric. “If you try to put some of this filter fabric over the top of the grate, it doesn’t let any water through. Then all of a sudden you start building up a pond. If the pond overflows the curb, and you happen to have a downslope, you’ve got real problems, because you have a liability issue. Plus, you can have vehicles driving by, and who knows-somebody could say “˜That caused me to have an accident, and destroyed my car.'”
He mentions other commonly used methods of protecting inlets. “From what I have seen, they typically put wattles around them, but they’re not terribly effective. For the drop guards, often they’ll use silt fence. But when you put silt fence around a raised drain, the wind and the water just knock it over, so it’s almost completely ineffective. The ERTEC product will actually allow the water to flow through, holding back the bulk of the sediment, which, of course, is the goal.
“Some of the older methods are like diapers that go into the drain inserts; that requires removing the grate and putting it in, and putting the grate back on. When it gets dirty or filled, you’ve got to go back and pull the grate off, empty it, and put it back in. It’s very labor-intensive. And the chances of injury are quite a bit greater, because these grates are heavy. It’s easy to get a finger crunched when you’re dealing with those things.
“The ERTEC Perimeter Guard we’re using doesn’t do any of that. It’s designed in a way that allows the flow through, but holds all the dirt and debris and stuff on top. So if it gets a little yucky, then whoever is maintaining it at that point in time can come by and clean it off very easily.”
Brown was pleased with the ease and speed of installation for this project. “For the guards themselves,” he says, “we had two men, and it took them approximately three hours to install 55 drain inlets. You won’t find anything else that is anywhere near this effective that will go in that quickly. And it is much easier to maintain and clean.”
Because the products can be reused on subsequent projects, he notes, “their overall costs are often only half of the competition on a job-to-job comparison. The fact that they are created from recycled material and are reusable and recyclable themselves give them a major “˜green’ advantage. So if they don’t get beaten up by traffic or by other subcontractors, we certainly try to reuse them whenever possible. That helps everybody.”
A variety of other BMPs are also being used on this project. “We installed the drain inlets, plus we put in a few thousand feet of ESA fence, and also two or three thousand feet of silt fence,” says Brown. “We finished what was required of us for that particular phase fairly quickly. We have gone back to make sure that everything is being maintained as it should be.”
The ESA fence, he explains, is a temporary fence for use in an environmentally sensitive area. “For example, if we do not want people to enter a construction area, then this fence will go up around the area. It also works the other way, too. Sometimes you don’t want construction people going over into these environmentally sensitive areas.
“It’s typically a 4-foot-high fence. You drive in T-posts or grape stakes, whatever the plans call for, then you string the fence up. It’s generally a protective thing to keep big vertebrates out, although I don’t think it will hold back an elephant!”
Brown notes that there is a small river running under the roadway, and there are a number of endangered species in the area, as well as a variety of snakes, salamanders, and other lizards. “As a result, a lot of work is necessary on that phase of it, to protect the environment, to protect animals. That’s not easy, because you have so much heavy equipment being used in that area. Sometimes it’s difficult to keep the fences up. But the ERTEC stuff we use holds up a lot better than anything else we’ve ever seen.”
While Brown notes that there weren’t particularly challenging engineering or access issues to deal with, he did encounter an occasional difficulty common to construction jobs.
“It’s just people being kind of careless,” he says. “They’re just human, and on these construction projects, not everybody necessarily cares as much as we might, about our phase. I’m not saying they’re out there doing anything intentionally-that’s not the case-but we’re all human, and things happen. A piece of equipment will hit our stuff, or someone has to push it aside, or knock it over to get in to do some of the work they need to do. Then maybe they don’t set it back up the way it should be. That’s typical of a lot of construction projects.”
Cleaning Up the Wicomico River
The city of Salisbury, MD, located on the Eastern Shore of the state, sits at the head of the Wicomico River, a navigable waterway feeding into Chesapeake Bay. Salisbury’s mayor, James Ireton Jr., promised several years ago to make the cleanup of this river a primary focus of his administration. “The cleanup of the Wicomico River for future generations must be at the heart of our efforts to revitalize our downtown, and ultimately the city as a whole,” he said at the time.
To assist with the river cleanup, the city contacted KriStar Enterprises, a national manufacturer of a variety of stormwater management products. Shawn Luton, a company vice president, handled the Wicomico River project.
“It was really an eyesore,” laments Luton, recalling his first sight of the river. “They had a myriad of items out there when I first saw the site, even a floating couch, believe it or not. It was a big issue. There was a lot of smaller litter and debris as well.
“That river is tidally influenced, so it does have some rise and fall, but when it’s not in high or low tide, it tends to be rather slow moving, so a lot of that trash and debris was relatively stagnant and obvious, especially in large curvatures of the river, where it would just congregate in the corner, in the eddies.” Abandoned barges also littered the river.
“They were working to put some units or some type of device on existing outfall pipe into the main Wicomico River that runs through the city,” Luton says, primarily to capture gross pollutants, large trash, and debris.
“We looked at existing outfall locations that could be accessible from a maintenance standpoint, as well as having pretty high visibility, so that it could showcase to the city residents that there was an effort being put forward by the city, and most especially by the mayor, to address the issue. That’s what led them to contact us, and for us to identify key locations near an adjacent overpass that would provide the maintenance accessibility, as well as highlighting the visibility of the project as a whole.”
At the start of the project, the outfall pipes simply dumped into the river, without any type of capture device. Asked if there had been any kind of grate protection, Luton says, “There was nothing other than just traditional upstream infrastructure, such as pipe and traditional catch basins with grate inlets, of course. But no filters on the upstream locations, or any kind of netting or trap on the outfall side-so basically just direct flow.”
On another phase of the river project, KriStar had installed 28 FloGard Plus catch basin inserts upstream of the outfall location. “These were drop inlets with grated inlets so we could capture the trash and the debris and sedimentation at the source,” Luton reports. “We did retrofit and apply those to existing locations upstream.”
For the outfall pipes, KriStar used two of its Net Tech Gross Pollutant Traps. One was a 24-inch circular unit attached to an existing 24-inch stormwater outfall pipe, and the other was a 36-inch circular unit.
“Typically, the devices are sized based on the size of the outfall pipe,” according to Luton. “We actually have an internal mechanism, a float mechanism, such that the debris captured will actually trip the device, so that it removes itself from the end of the pipe and becomes tethered off to the side. It holds itself there until they can come and maintain it. So there’s really not a flow maximum to be concerned with, because once we get enough trash debris accumulated in the netting device, that in turn will back up the hydraulic grid line, which will let the float valve rise. Once that trips, it will remove itself to prevent upstream flooding. That’s the design of the unit.
“There is some consideration typically given to the net opening size, depending on the debris and whether you have a larger or smaller pipe. But basically, we just determine the size of the Net Tech system based on the size of the outfall pipe.”
The primary concern of the city of Salisbury was the removal of the offensive debris. At the present time, the city is not quantifying or measuring the amount of pollutants being removed from the river.
“They were just after trash, debris, gross pollutants,” says Luton. “They primarily wanted to make an impact with the citizens, showing them that they were actually removing it, getting trash and debris out.”
While Luton is not aware of Salisbury’s maintenance plans for the Net Tech units, he explains how maintenance is usually handled. “What typically happens is they should be monitoring after most large storm events, to see what is being captured, and making assessments based on the current volume of trash that has accumulated. With these being in high profile, really visible areas, they should be pretty up to speed. It’s also pretty close to the city public works department, so I’m sure they’re checking those routinely.
“As far as a maintenance interval and what they’re actually capturing, a lot of that will be seasonal as well. For example, in leaf season, in the fall, they’re going to be expecting a lot of leaf debris, more so than in other parts of the year.”
He notes that the nearby city of Easton now has a routine maintenance schedule. “They are making sure that they capture and retain for monitoring purpose just what’s in those devices. They don’t want it to sit too long and degrade and filter back into the watershed, or to get caught and cause the device to lose some of the debris that accumulated.
“We have about five additional Net Techs installed there in Easton, and they are quantifying whatever they catch, hauling off the debris. They’re drying it, weighing it, and actually monitoring and tabulating what they’re getting from those locations. I believe that there has been grant funding secured from the Chesapeake Bay Foundation, allowing Easton to do the testing and the monitoring.”
An interesting aspect of the Salisbury project was dealing with the tidal influence on the Wicomico River. “It was challenging,” Luton says. “We were trying to time the tide accordingly. Our Field Services division came up from Atlanta, so we were trying to plan in advance, to schedule work with weather, watching if there was rain forecast for the area. We also had the tidal influences we had to chart.
“We had the city provide boat access for us. We had a guy in a boat in the water. I was on the surface, operating the boom truck to lower the device down to him. We had to do some upstream sandbagging, added a seawater pump to keep water upstream, because it’s a pretty extensive upstream network that was pouring into the stream.
“We had to offset a lot of the prior rain events that were still percolating through and saturating the system, reaching the water, even though the rain events weren’t in the area of the install. So there was quite a bit involved with logistics in getting it dewatered, getting access from the water side, and setting up the boom truck and lowering the unit down. It was a pretty in-depth install.”
Fort Belvoir Inlet Protection
Fort Belvoir, located in Fairfax County, VA, is home to approximately 7,100 permanent residents, but more than 50,000 military personnel and employees work at the base, which is just minutes away from Washington, DC. According to the Fort Belvoir website, the base provides “logistical, intelligence, medical, administrative support, and command and control for a mix of more than 140 commands and agencies for the Department of Defense.”
Steve Gross, project engineer with Bowen Engineering, has been performing work for the base since the summer of 2011. “What we’re doing is replacing existing water line pipe onsite, about 160,000 linear feet of pipe,” he says.
“One big concern we had was replacing the pipe while protecting the existing stormwater management system onsite. We tried a couple different methods. For example, we tried hay bales to protect the inlets, but that didn’t really work very well. For inlet protection, we also tried using silt fence on some of the storm drains, but as with the hay bales, it just didn’t really work.
“Then we came across Gator Guard wattles, and we’ve been using them now for some time. We found them to be really helpful and useful. They’ve been protecting all of our onsite storm drain inlets. They have been working out really well. But we are using silt fence for the runoff, the sheet flows offsite.”
Gross notes that while the government base isn’t quantifying improvement to its storm inlets, it is concerned with quality control. “They had a team of erosion control inspectors out here that monitor what we’re placing, and we follow what they say. If they say something doesn’t work right, then we try to think of something better to do to meet their needs. But basically they just want us to handle any runoff and protect all existing stormwater systems.”
To date, the inspectors are pleased with the results. “They’re very happy with what we’ve been doing,” Gross reports. “Ever since we’ve implemented the Gator Guards, we’ve been getting great feedback from them.”
Bowen Engineering also makes sure that ongoing maintenance takes place. “After every major rainstorm, we check all the inlets onsite and make sure that all the protective measures are still in place and still operating correctly,” says Gross. “Usually after a major rainstorm, there is some sediment that builds up around the Gator Guards. We basically just take a shovel and clean it out, and they continue to work perfectly fine.”
He also mentions that there are nearby sensitive habitats, consisting of Resource Protection Areas and wetlands, “but we’re basically not allowed to go anywhere near them, so we haven’t run into any problems with these areas.”
Another concern that Fort Belvoir staff had was that the trees on the base not be damaged in any way. “There are some really, really old trees on this base, and when we’re laying all this pipe, sometimes you have to get pretty close to the trees,” says Gross. “We’ve had to go above and beyond in order to stay as far away from the trees as possible. We’ve had to place tree protection around trees that may not really need tree protection, but it’s better to have it than not have it. Some of the trees are over 100 years old.
“It’s a very rare case where we’re allowed to remove a tree. They would much rather put 20 bends in a pipe to get around a tree rather than shooting straight underneath it, and thereby kill the roots and the tree.”
Long Island Sound Rebounds
Long Island Sound is a large body of water bordered by the state of Connecticut on the north and by Long Island, NY, on the south. In the late 1980s, Long Island Sound was in deplorable shape.
According to Soundkeeper, a nonprofit group dedicated to improving the waterway, the harbors of Long Island Sound were full of dead and dying fish, and dissolved oxygen levels plummeted to zero in western stretches of the sound. Even more disgusting was the medical waste washing ashore, including body parts, syringes, and used bandages. Hydrogen sulfide in the water produced a strong rotten-egg odor.
The city of Norwalk, CT, was one of the first communities along the sound to agree to clean up the estuary. In recent years, the city has instituted what it calls the Filter Project to reduce the amount of polluted urban stormwater runoff reaching Long Island Sound.
The project involved fitting 275 storm drains in the area with Ultra Urban Filters equipped with Smart Sponge Plus from AbTech Industries.
These filters are intended to treat stormwater runoff for new or retrofitted sites by absorbing oil and grease and capturing trash and sediment.
In addition, the Smart Sponge Plus technology utilizes an antimicrobial agent that is effective in reducing coliform bacteria that may be found in stormwater, industrial wastewater, and municipal wastewater.
Two types of filters are available, depending on the stormwater drain. A modular unit is used for curb inlet openings, and a single unit design is used for typical drop-in catch basin drains.
The Ultra Urban Filter is constructed of high-strength corrugated recycled plastic. Trash and sediment accumulate in the upper basket chamber, while oil and grease are absorbed in the unit’s filtration media.
Soundkeeper reports that two years after installation, E. coli and coliform bacteria were reduced by 75% in waters flowing to the sound from the test drainage area with the 275 storm drain filters. As high as 99% reduction of E. coli was observed at some test locations.
The organization notes that each Ultra Urban Filter is capable of capturing and retaining up to five times its own weight in hydrocarbons and other pollutants.
According to AbTech, the first cleaning of the 275 catch basins yielded over 7.4 tons of trash, debris, leaves, and sediment.
After two years, AbTech estimated that over 38,000 pounds of various contaminants and pollutants had been prevented from entering Long Island Sound.
The company reports conducting what it refers to as a “black-box characterization,” which involved the deconstruction or meltdown of used Smart Sponge media to determine what contaminants were trapped within the media itself. AbTech found that approximately 49 pounds of contaminants were captured with the Smart Sponge of each filter, including heavy metals (copper, titanium, and zinc) and a variety of hydrocarbons (consisting of oils, solvents, cosmetic product components, and chemical plasticizers). This additional captured matter totaled an additional 13,500 pounds of removed contaminants.
