CDOT readies for construction of big game underpasses east of Fort Garland
THE Colorado Department of Transportation is getting ready to begin construction on a series of big-game underpasses through a 7-mile stretch east of Fort Garland and onto La Veta Pass.
“We’ll start there on the eastern edge with our exclusion fence, which is our eight-foot-tall fence, for 6.9 miles to the east. So it’ll stretch all the way across that kind of sage brush shrub right before US 160 drops down to Sangre de Cristo Creek, so that’s 6.9 miles. We can call it seven. And within that span of seven miles of fence, we’ll put in three large-game crossing structures,” said Colorado Department of Transportation biologist Mark Lawler.
Lawler and CDOT have been planning for the project since before 2020 and plan to complete what is known as the US 160 Fort Garland East safety mitigation project over the next two summer construction seasons.
One goal of the project is to disturb the natural brush and Sangre de Cristo Creek as little as possible to keep the area inviting to migrating wildlife.
“We have a great deal of confidence that these will work super with our target species. Out there we see hundreds of mule deer and hundreds of elk, if not thousands. So those would be the species and those kind of dictate some of the dimensions of these underpasses.
“They’ll be large, although they won’t be visible to drivers. These structures are well over 20 feet, potentially 25 to 29 feet wide, and they’re about 13 feet tall. We find that that’s a size that mule deer readily use and elk also have used structures of this size and all three of these locations are terrific. We’ve already seen a lot of animal movement through there. We’ll have good luck moving them through structures of this size, but they’ll all be underpasses, no big overpasses that people will be able to see.”
An 8-foot-tall exclusion fence will stretch along the highway for the 7-mile span of the project to deter deer and elk away from the roadway and to use the underpasses.
Law enforcement reporting of where crashes occur and carcass removal data from CDOT supported the placement of the project. Here, a deer carcass awaits removal near Fort Garland.
ALAMOSA Citizen interviewed Lawler on May 4 to better understand the project. What follows is an edited QA:
CITIZEN SUNDAY Q&A
We want to talk about the upcoming US 160 Fort Garland East safety mitigation project. The construction, I believe, is set to begin here in June. Is that right?
It’ll be this summer. We’re finalizing the plans and getting a lot of the very last authorizations. It’ll need to go through an advertisement and bid process, but absolutely, this summer we plan to kick off out there east of Fort Garland.
Before we get into the specifics of the project, what’s been the process just to get to the stage of putting the project out for bid and begin construction?
You’re right. A lot of moving parts to finally get a project underway. I’m with the CDOT Environmental Program, so I could talk in detail about that process and what we need to do, but there’s a lot of other things that are going on and processes that are underway simultaneously as the environmental review. Things such as our utilities, our right of way, and then of course making plans that meet state and federal laws. But at least for me, we adhere to a National Environmental Policy Act process because we receive federal money from the Federal Highway Administration. So that’s a big part of my pre-construction effort is to make sure that we meet all of the NEPA requirements for this project … Items like archeology and history, our Endangered Species Act compliance, on and on. There’s a lot of resources in that area. We want to make sure that we don’t impact them unnecessarily and make sure that we can put conservation in place to minimize our work out there.
This corridor that we’re talking about, the Fort Garland area, going into La Veta pass, were there any extra challenges to you as you think about that particular corridor and the different land ownership in there?
Well, there’s kind of two layers to that perhaps. One is we’re always working with the big land agencies, especially when we’re talking about wildlife connectivity and trying to have a big-picture view on where the animals move, where we see pinch points and bottlenecks, where we see areas that have a lot of potential to maintain permeability, install permeability.
So yes, we work with the BLM and the service a lot. For this specific project, the seven, eight miles that we’re going to treat are all private lands adjacent, minus the town of Fort Garland there at the very western terminus. So we didn’t have any direct coordination as far as needing to get permits or evaluate forest service or BLM sensitive species. But in the big picture, we certainly do, in this case, the one agency that we work with a lot, even though they don’t have adjacent lands, is of course Colorado Parks and Wildlife. Any time we’re doing something wildlife related, we want to engage them early and get their input. It’s invaluable and essential.
The project will include three underpasses that will not be visible to drivers. The crossings will be 25 to 29 feet side and about 13 feet tall, large enough to accommodate the hundreds of mule deer and elk that regularly cross the highway.
The US 160 Fort Garland East safety mitigation project begins at mile marker 258 at the edge of Fort Garland and will continue about 7 miles east of town.
What generally is the wildlife population in this corridor, which as you know, butts against the Forbes Trinchera area and up onto La Veta Pass. What about just the wildlife population in this corridor particularly?
That would have to be a question for our CPW staff. I can tell you what we see from the conflict, the kind of accident rates and the carcasses that we’re removing from US 160. But as far as total numbers, that would be better answered by the experts who really look into these numbers and those are the folks with Colorado Parks and Wildlife. So an absolute number. I don’t have that.
Gotcha. How do you determine the specific location of the project? What’s that based on?
A lot of items are used to try to define these locations. Again, kind of the big picture and then we can talk about this project. CDOT and Colorado Parks and Wildlife several years ago sat down and worked together for a number of months to try to establish roadway segments on the west slope of Colorado that need to be prioritized for some kind of safety measures to reduce conflict between motorists and wildlife. We looked at the entire west slope and slowly put together a list of those roadway segments that we wanted to look at and have some kind of treatment put in place right away.
And that looked at future growth, that looked at existing migratory movements. We looked at our habitat, so what ranges we have, whether it’s summer or winter range for some of these large game. And then of course we also then use a lot of CDOT’s data and that includes our law enforcement reporting where we have crashes recorded, and then we also have our carcass removal data that’s put together by our CDOT maintenance patrols as they pull animals off the roadway. Kind of a dark aspect, but invaluable data for us to find out where we see a lot of conflict and if that’s a spot where also we need to ensure movement for wildlife. Now we’re starting to put together a bit of a bullseye on some of these spots. In a lot of locations we try to use parks and wildlife radio collar data, so we have pretty good bullseye information where the animals are moving.
We will go to the project sites with Colorado Parks and Wildlife staff, walk these projects. Literally look for game trails, look for landscape features such as draws and ridges and look at cover areas that might provide shelter or cover for traveling larger game. And we start looking then at the roadway, what opportunities does the roadways, topography, and locations afford us? Getting a big structure underneath the roadway or over the roadway can use a little help from mother nature. We need a drainage. We need something that provides us a fill slope that we can put a structure in or connect. So all those things together allow us to slowly develop some locations we think will be really conducive to the wildlife movement, but also provide benefit to the motorists by keeping the animals off the roadway. So, man, what a loaded question. That’s a big deal. We take that real serious finding out where we’re going to put these structures and where we’re going to put this fence. This and a big part of it’s working with Parks and Wildlife and adjacent landowners. This project’s been underway for me at least for years and years. We’ve been looking at this, meeting on site, discussing it, scratching our heads. So yeah, a lot of thought goes into that.
“We’re already seeing the movements across the roadway, so we’re just giving them a nudge. They’re already doing it.”
Did the area become more of a priority through the years as CDOT was seeing an increase in the volume of traffic coming into the Great Sand dunes when it became a national park?
I don’t know the exact traffic volume increases associated with the national park. We do know that US 160 through that corridor is seeing increased traffic volumes. The level right now, which I believe last time I looked was between 6,000 – I have it right here, 6-7,000 – is our annual average daily trips. That’s a lot of cars. It also is a level that’s pretty challenging for wildlife to get across. It’s just enough that they’ll approach the roadway and try to time it, but it’s also just enough that, of course we see a lot of collisions because the volume’s high. It is growing. I don’t have that number in front of me. Our traffic and safety program is on top of all that. But we do know it’s growing. We can see that, which is another reason we were getting this safety project underway out there because not only will it work to reduce our wildlife vehicle collisions, it also has an intersection of improvement in it because we’ve seen that that was a safety concern and it’s somewhat associated with increasing traffic volumes.
What is the length of this project in terms of mileage? Take us through the specific crossing points coming up.
So it’s going to start, as the name implies, immediately east of Fort Garland. You’re working with the CDOT guy here, so I do mileposts. So we’ll call that milepost 258 is Fort Garland. We’ll start there on the eastern edge with our exclusion fence, which is our eight-foot-tall fence, for 6.9 miles to the east. So it’ll stretch all the way across that kind of sage brush shrub right before US 160 drops down to Sangre de Cristo Creek, so that’s 6.9 miles. We can call it seven. And within that span of seven miles of fence, we’ll put in three large game crossing structures. They’re all associated with natural draws that are out there because those give us our topography to contain a big structure. Fortunately, each of these draws was already seeing a lot of wildlife movement, so we’re really pleased that those needs have aligned.
Is this project an overpass or underpass, or can you describe the design that people ultimately will see?
This will be three underpasses. That’s what the terrain will offer us. We have a great deal of confidence that these will work super with our target species. Out there we see hundreds of mule deer and hundreds of elk, if not thousands. So those would be the species and those kind of dictate some of the dimensions of these underpasses. They’ll be large, although they won’t be visible to drivers. These structures are well over 20 feet, potentially 25 to 29 feet wide, and they’re about 13 feet tall. We find that that’s a size that mule deer readily use and elk also have used structures of this size and all three of these locations are terrific. We’ve already seen a lot of animal movement through there. We’ll have good luck moving them through structures of this size, but they’ll all be underpasses, no big overpasses that people will be able to see.
Are the patterns that wildlife follow, are those patterns disrupted and how do wildlife respond as the construction is happening and then completed.
It is a construction project and we are asking a little bit of the animals to work with us so that they can get across the road safely as well. A lot of it goes back to what we were discussing moments ago. We really tried to put these structures in spots of known movement for us, and in trying to provide safety on the roadways for motorists and wildlife, we look at spots where we see a lot of hits, where we see a lot of carcasses removed, and then we also then work with parks and wildlife on where they’ve observed and where they are confident the animals are moving. So then we try to combine those two so we get the benefit of reducing the collisions, but we still preserve some of those movement corridors that the animals have routinely used for so many years. In this case out there we have two movements as well.
We have a big seasonal movement that’s early winter, and then in the spring as these animals travel from winter to summer ranges; they like to winter there along Sangre de Cristo Creek and then out in the San Luis Valley proper, and then they move back up into those foothills of Lindsey and Blanca and up in that terrain and even wrap around to the Wet Mountain valley. So they’re big movements, large volume, the animals are moving fairly steadily. That’s kind of our migratory movement. Then we also see daily movements, and this is especially pronounced in the winter when the animals are on their winter range. So we put in a lot of erosion and sediment control measures to make sure that we’re managing our storm waters run on runoff. Sangre de Cristo Creek’s a very important stream. We want to make sure that we don’t increase turbidity or cause deposition down there. So we are putting measures in as we construct, try to preserve resources that may be off-site and make sure that we don’t have that long lingering effect on the environment.
What are the anticipated benefits and how much are wildlife-vehicle crashes reduced through these wildlife mitigation projects?
“The wildlife mitigation out there really is just going to keep animals off the road. It is going to allow them to cross under 160 in several locations where they were already crossing.”
So in north central Colorado they’ve seen a reduction, almost 90 percent up there in wildlife-vehicle collisions. That was a terrific treatment. Adjacent landowners have worked really hard to make sure that the fence is tight, that animals aren’t getting in the roadway. So that was a very successful treatment. We want that. That’s our goal. We don’t always have that. Sometimes it’s slightly less. Perhaps our fence was shorter, perhaps we have open gates, different things that can affect whether or not wildlife get in the corridor and are struck and involved in a crash. But we always see positive results and always see certainly a worthwhile benefit.
The archeological assets that you talk about sounds interesting. Anything that you are anticipating or watching for in the Fort Garland East Safety project? As a biologist, anything that you are paying attention to on this particular project?
For me as a biologist, beyond just making sure the large game cooperate and that we are able to benefit the motorists and keep a lot of animals moving through there, some of the resources that are important would be Sangre de Cristo Creek down slope of the project. We have three drainages that all discharge to Sangre de Cristo Creek that we’ll be impacting. So I want to make sure we don’t change our water quality. We do have a little piece, a little arm of wetland off Sangre de Cristo Creek that will have some temporary impacts. So we’re going to make sure we get that restored, reclaimed, really kind of repeating myself on what we’re doing to avoid any indirect impacts. We’re going to make sure our seeding comes in well. That’s important to make sure the wildlife find these structures attractive and not so artificial so they use them more readily and in greater numbers. That sagebrush shrubbing out there is beautiful.
What else should we know about the upcoming Wildlife Mitigation project that we haven’t talked about? What else should people be aware of or what should they know about?
The wildlife mitigation out there really is just going to keep animals off the road. It is going to allow them to cross under 160 in several locations where they were already crossing. It doesn’t contain or constrain movements at all. All the fencing is on our right-of-way line. It doesn’t leave the roadway corridor. So we don’t contain these animals. We may affect their movements slightly, but that is just to guide them to these structures so that they go beneath the road and we don’t see the mortality when they do at grave crossings. I think that’s important for folks to know. We’re not moving the animals around on the landscape in a big way. We’re just moving them potentially a little bit so that they can use these structures. This is a motivated herd. They want to get to those winter ranges, they want to access that habitat. We’re already seeing the movements across the roadway, so we’re just giving them a nudge. They’re already doing it.