Estimating road age and traffic volume for disturbance assessments in Wyoming Active
In 2021, the Fort Collins Science Center initiated a research effort to estimate road age and annual traffic volumes across the majority of roads in Wyoming for assessing impacts to wildlife. Data on roads often focus on the ‘where’ (for example, spatial features) but neglect the ‘when’ (for example, road age) or ‘how much’ (for example, traffic volume). Knowing these characteristics is critical for assessing the cumulative impact of roads and their associated vehicular traffic on ecosystems. This project addresses each by providing estimates of road age and traffic volume for 1986 – 2020 across highways, arterials, collectors, local, and gravel/graded roads within the state of Wyoming.
Background
To balance multiple land management priorities, conservation and management practitioners rely on accurate inventories of biological, cultural, and natural resources, as well as the disturbances that can degrade them. Knowing how long and to what degree disturbances have been affecting an ecosystem is critical for assessing the true effectiveness of land management actions because the severity of a disturbance may change over time. Linear features such as roads are often overlooked as a source of ecological disturbance, but their associated vehicular traffic can act as disturbances to many terrestrial systems and cause habitat degradation, functional habitat loss, and direct mortality. Studies of these effects often focus on the ‘where’ (for example, road location) but neglect the ‘when’ (for example, road changes through time) or ‘how much’ (for example, traffic volume). Knowing these characteristics is critical for assessing the effect of roads and their associated vehicular traffic on ecosystems and improving the effectiveness of land management actions targeted at mitigating these effects.
Project Goals and Anticipated Outcomes
In this work we are developing a new dataset that can be used to study the effects roads may have on adjacent ecosystems in Wyoming. Specifically, we are developing annual estimates of road age and vehicular traffic volume across highways, arterials, collectors, local, and gravel/graded roads within the state of Wyoming. These data can help managers ask broad questions about habitat fragmentation or identify which roads may offer an opportunity to implement temporary road closures or traffic restrictions, including limiting trucks, to increase connectivity between populations. More broadly, these metrics of road age and traffic volume help address the ‘when’ and the ‘how much’ questions of how roads may be affecting people, wildlife and landscapes we care about. These new data also have the potential to inform resource management planning where knowledge of the effects of roads and traffic volume are needed.
Methods
Traffic volume is defined as the number of vehicles transiting a section of road during a given time period and is one of the many characteristics that impact the severity of adverse effects on nearby habitat (e.g., degradation and loss), wildlife (e.g., direct mortality), and their populations (e.g., genetic isolation and decline).
To measure road age, we are using data on surface disturbances (e.g., oil & gas drilling operations, wind turbines, and open pit mines) with known establishment dates in combination with graph theory and centrality metrics to estimate the age of each road. By estimating road age, we can ensure that annual predictions of traffic volume are not assigned to roads prior to when they were built.
We are also developing predictions of annual traffic by relating ongoing traffic monitoring data from the Wyoming Department of Transportation with a set of variables that may explain traffic patterns across large regions, including:
- roadway characteristics (for example, speed limit),
- transportation network access (for example, distance to nearest freeway or interstate),
- socioeconomic characteristics (for example, number of registered drivers in nearest town),
- land-use (for example, distance to nearest recreational opportunity).
In 2021, the Fort Collins Science Center initiated a research effort to estimate road age and annual traffic volumes across the majority of roads in Wyoming for assessing impacts to wildlife. Data on roads often focus on the ‘where’ (for example, spatial features) but neglect the ‘when’ (for example, road age) or ‘how much’ (for example, traffic volume). Knowing these characteristics is critical for assessing the cumulative impact of roads and their associated vehicular traffic on ecosystems. This project addresses each by providing estimates of road age and traffic volume for 1986 – 2020 across highways, arterials, collectors, local, and gravel/graded roads within the state of Wyoming.
Background
To balance multiple land management priorities, conservation and management practitioners rely on accurate inventories of biological, cultural, and natural resources, as well as the disturbances that can degrade them. Knowing how long and to what degree disturbances have been affecting an ecosystem is critical for assessing the true effectiveness of land management actions because the severity of a disturbance may change over time. Linear features such as roads are often overlooked as a source of ecological disturbance, but their associated vehicular traffic can act as disturbances to many terrestrial systems and cause habitat degradation, functional habitat loss, and direct mortality. Studies of these effects often focus on the ‘where’ (for example, road location) but neglect the ‘when’ (for example, road changes through time) or ‘how much’ (for example, traffic volume). Knowing these characteristics is critical for assessing the effect of roads and their associated vehicular traffic on ecosystems and improving the effectiveness of land management actions targeted at mitigating these effects.
Project Goals and Anticipated Outcomes
In this work we are developing a new dataset that can be used to study the effects roads may have on adjacent ecosystems in Wyoming. Specifically, we are developing annual estimates of road age and vehicular traffic volume across highways, arterials, collectors, local, and gravel/graded roads within the state of Wyoming. These data can help managers ask broad questions about habitat fragmentation or identify which roads may offer an opportunity to implement temporary road closures or traffic restrictions, including limiting trucks, to increase connectivity between populations. More broadly, these metrics of road age and traffic volume help address the ‘when’ and the ‘how much’ questions of how roads may be affecting people, wildlife and landscapes we care about. These new data also have the potential to inform resource management planning where knowledge of the effects of roads and traffic volume are needed.
Methods
Traffic volume is defined as the number of vehicles transiting a section of road during a given time period and is one of the many characteristics that impact the severity of adverse effects on nearby habitat (e.g., degradation and loss), wildlife (e.g., direct mortality), and their populations (e.g., genetic isolation and decline).
To measure road age, we are using data on surface disturbances (e.g., oil & gas drilling operations, wind turbines, and open pit mines) with known establishment dates in combination with graph theory and centrality metrics to estimate the age of each road. By estimating road age, we can ensure that annual predictions of traffic volume are not assigned to roads prior to when they were built.
We are also developing predictions of annual traffic by relating ongoing traffic monitoring data from the Wyoming Department of Transportation with a set of variables that may explain traffic patterns across large regions, including:
- roadway characteristics (for example, speed limit),
- transportation network access (for example, distance to nearest freeway or interstate),
- socioeconomic characteristics (for example, number of registered drivers in nearest town),
- land-use (for example, distance to nearest recreational opportunity).