Better Roads Staff
“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.
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