Better Roads Staff | September 7, 2011
It Doesn’t Have to be a Jungle Out There
By Mike Anderson
Call it a rule of thumb: It is always easier to find funds – no matter how bare the funding cupboard – for a taxpayer-jolting pothole than for neglected roadside vegetation or rock riprap. Ask any maintenance manager.
Too often, it appears, roadside vegetation is not, well, given its fair share of weight in planning and thinking about overall road management strategies and fund dispersal in these tough economic times. And that mindset can turn out to be costly. If budget can be found for products and applications that control, maybe even prevent, deterioration beside the road, there are true long-term benefits, including financially, say industry suppliers.
“I think we don’t fully account the cost of a solution that is our ‘go-to’ solution,” says Paul O’Malley, national market development director, Landmark Earth Solutions. “We take for granted and we turn a blind eye to what I often call the hidden costs. What is it truly costing for a piece of equipment to get out there and do the repair, for example, or to have your workers going back out to that site on a more frequent basis, versus the other needs that you need to be managing? It seems to me that these hidden costs are just sort of an accepted practice.
“My advice for agencies and contractors is to truly do an objective analysis of what the costs are of what you are currently doing versus some of the alternatives that are out there.”
Let’s take, by way of example, what industry leaders are offering in three specific areas of roadside maintenance:
1. Vegetation Management
Asked for his perspective of the market today, DuPont’s Darin Sloan couldn’t resist. “From my perspective, it’s funny that you use that term. We’re right in the middle of a launch of a new herbicide for roadside management – we got our first state registration in February of this year – and the name of the product is Perspective.”
Maintenance is an area that all too often we have become conditioned to not really scrutinize as effectively or as aggressively as we should.
– Paul O’Malley, Landmark Earth Solutions
Based on a new DuPont chemical called aminocyclopyrachlor used in various non-crop applications, Perspective is being promoted across the country as a tool for managing a range of roadside vegetation conditions, from line-of-sight safety issues in the faster-growing East to erosion-causing invasive weeds in the West. “As you move west, the roadsides don’t get the same amount of rainfall and, therefore, the uncontrolled vegetation part, the safety part, is not as big of a concern as the degradation of the natural environment due to invasive weeds,” says Sloan, a land management business portfolio manager. “In the Western part of the U.S., there are actually state and federal laws that require these road crews to manage invasive or noxious weeds on their roadsides.” Perspective has a “spectrum of control” on these hard-to-control invasive weeds, including leafy spurge, knapweed and thistle complex, he says.
Across the country, species that built a resistance to traditional herbicides, including Russian thistle, resistant marestail and resistant kochia, can be managed by crews with the same aminocyclopyrachlor chemical product applied to more normal vegetation management such as perennial broadleaf weeds. “As resistance developed, what would happen is they’d have weed escapes. They’d have to come back and plan another herbicide application to basically go over the same acres they sprayed before,” explains Sloan. “This new product will do it right the first time. They won’t have to come back and get these resistant species, not to mention some of those invasive species that really just didn’t have a good solution. Leafy spurge is sort of the poster child for that – it really has not had a good commercial solution in the past for control.”
Perspective “can also deliver some fiscal benefits, when you start comparing herbicide programs to mowing programs and the ability to eliminate some of the mowing cycles they have in-season,” says Sloan. Particularly in the East, “we can go out in the fall, which is relatively new in this marketplace, and provide residual weed control through the fall and the spring. That’s where they start seeing the benefits of reducing the amount of mowings that they have to do, or at least delaying the mowings until further into the summer.”
Primarily for broadleaf weed control, one application of Perspective per season should suffice, he says, adding that a follow-up product such as Pastora is required for areas with grass issues, such as the Southern and particularly Southeastern states.
“For those areas, we’re going to be actively promoting a two-pass system, if you will,” says Sloan. “You start the season off with Perspective and keep the roadsides clean until the beginning of summer, and then when you’ve got Johnsongrass and Dallisgrass and some of the undesirable grasses coming up, hit it with a Pastora treatment. From an herbicide application standpoint, that will pretty much be all you’ll need.
“You’ll probably have to come in and mow a couple of times in that summertime period,” Sloan continues, “but from a weed-control standpoint, you’ll be sitting pretty good.”
For product info, visit: dupont.com/Land_Management/en_US/products_services/herbicides/Perspective_herbicide.html
2. Erosion Control
O’Malley isn’t so much against rock riprap as a roadside armor against water erosion or scour; he just believes his company’s transition mat solution is more reliable, especially considering the lack of resources agencies have to tend to required riprap maintenance.
Maintenance, he says, “is an area that all too often we have become conditioned to not really scrutinize as effectively or as aggressively as we should. It seems like all too often we are focused on the initial construction cost of a project, and there’s not a due-diligence process applied to the lifecycle costs of that project. Sometimes decisions are made in favor of perhaps what appears to be a lower construction cost, and the cost we pay for that is a higher lifecycle cost and that is where the maintenance departments are faced with the burden.”
Case in point: rock riprap, he says.
“Anytime we have erosion-control needs, where vegetation is deemed to be not an ideal choice – either because there are hydraulic conditions that the vegetation cannot withstand or perhaps the soils cannot support effective vegetation because of slopes or just poor soil conditions in general – we see people using rock riprap,” says O’Malley. Hard-armor riprap is “the ultimate Band-Aid.” It is, he says, dependent upon a product that is local in nature, and, hence, inconsistent in both property and availability, as well as increasingly unpopular aesthetically.
“More importantly, we see a solution that requires continual maintenance that is very costly, because of the equipment that’s needed, and also very dangerous. When we put rock riprap on the side of the road, along the slopes or the drainage areas adjacent the roads, inevitably we get some type of vegetation growing up through it. That vegetation requires maintenance, and it is very difficult because of the precarious footing to get in there and maintain it without risking worker safety.”
ScourStop is Landmark’s product name for its transition mat – a mechanically anchored, semi-rigid, polymer mat with voids throughout for vegetative growth.
“From a vegetation maintenance perspective, it’s a flat, safe surface, so people can maintain the ScourStop system’s vegetation with traditional maintenance equipment. It doesn’t create an unsafe condition to go and maintain it,” says O’Malley. “From a hydraulic perspective, there’s no maintenance needed. If we have a 10- or a 25- or a 50-year design event come through, the system is designed and installed to support that event. So, there is no reshaping that needs to happen; you don’t have to go back in and add new panels; you simply maintain whatever vegetation is there in a very safe manner.”
Federal laws dictate that rock riprap must be reshaped, re-graded and have product added to it after every major climatic event, says O’Malley, “and that’s one of those things that maintenance departments just do not have the budget for. The only maintenance the rock is really typically seeing is someone with a string trimmer trying to go in and balance himself on different boulders and cut the weeds that are growing up through without killing himself in the process. No one is talking about going and adding new rock, and re-grading the rock, and making sure that it’s meeting the hydraulic requirements of the drainage conveyance, for example.”
In areas such as the Upper Midwest or Southeast, ScourStop can be installed in combination with sod; in drier areas, it is recommended to simply adjust the soil cover component and incorporate a turf reinforcement mat; where there is continual flow, don’t rely on any vegetation and just use the geotextile layer.
For product info, visit: scourstop.com
3. Culvert Rehab
The advantage to slip-lining a culvert to restore its design strength and life is also the Snap-Tite product’s biggest market challenge, says David Hundley.
A product line of ISCO Industries, Snap-Tite is marketed to state and local agencies on the basis that in-house crews can do the installations themselves. “They don’t have to put out for a bid process, so there’s a big savings in that,” says Hundley, Snap-Tite’s director of sales. And there’s undoubtedly a need, he relays. “You ask, ‘Do you have any bad culverts in your district or your county?’ and the answer is, ‘Do I ever! Of course, I do,’” he says. “These things were originally put in in the ‘50s and ‘60s, and they have design life of 30 to 40 years, so that design life has long come and gone. The solution to that has been historically to just dig them up, and that is such a big inconvenience that what ends up happening is the agencies just don’t do anything. They fix them when they fail, when the road collapses and everything gives way off the side.”
But an agency’s maintenance budget, already squeezed in this recession era, tends to go first to needs that are publicly both visible and prioritized, such as mowing, salting and guardrail replacement, says Hundley. “You take a small town. It might cost them $25,000, even if they use their own crews to fix this. That might be a $100,000 saving, but they didn’t have $25,000 extra to start with.” And, in the meantime, guardrails are missing, grass is growing and, he says, the public is howling.
Then again, the emergency alternatives to a no-dig solution like Snap-Tite are even more inconvenient to the public. “The only other way to fix this is to pull these culverts up, pull them out and put new ones in,” says Hundley, “and that stops traffic, shuts down roads, and all those things the public doesn’t want. Cost-wise, you’re looking at five to ten times more to do that type of work, versus just fixing it without having to dig it up.”
Meeting the American Association of State Highway and Transportation Officials (AASHTO) requirement for culvert repair, the Snap-Tite lining system uses a heavy-duty plastic – high-density polyethylene (HDPE) – pipe on which a male and female joint is milled. The pieces “literally snap together” with a simple “chain-and-come-along” apparatus already found in stock at most city, county and state work sheds. “Once it’s snapped together on the side of the road or in the ditch, you literally take that stick of pipe and insert it into the old culvert that’s rusted out or that concrete structure that’s shifted, given way or worn out,” says Hundley. The space between the old and new pipe, and any other voids created over the years, are then filled in with a milkshake-type grout mix, injected via PVC tubes inserted as access points as the gaps at each end of the culvert are first sealed up. “That mix will find its way through all those holes and fill in all the areas that have been washed out.”
In addition to the official 100-year lifespan of HDPE, the culvert insert provides a slicker alternative to the traditional corrugated piping and, “because we go down in size when we fit a new one into an old one, the flow of runoff is increased.”
For product info, visit: culvert-rehab.com
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