Colorado has a bunch of these, albeit on a smaller scale. Colorado Parks & Wildlife released a study on the effectiveness of these. https://cpw.state.co.us/hwy

Colorado has a bunch of these, albeit on a smaller scale. Colorado Parks & Wildlife released a study on the effectiveness of these. https://cpw.state.co.us/hwy9 https://cpw.state.co.us/hwy9 > The research documented 112,678 mule deer successful passages through or over the seven crossing structures. Combined with an overall success rate of 96% of mule deer utilizing the structures, these results indicate that the project has been highly effective in accommodating mule deer movement.