Section 4(f) Evaluation

Section 4(f) of the Department of Transportation Act of 1966 (Regulations at 23 CFR Part 774)

Section 4(f) was created when the United States Department of Transportation (USDOT) was formed in 1966. It was initially codified in Section 4(f) of the USDOT Act of 1966 which is where it got its name. Section 4(f) prohibits the use of publicly owned land of a public park, recreation area, or wildlife refuge of national, state, or local significance, or land of a historic site of national, state or local significance unless FHWA determines that there is no "feasible and prudent" avoidance alternative and that all possible planning to minimize harm has occurred. Section 4(f) only applies to actions of the US Department of Transportation (USDOT) and applies to Colorado Department of Transportation activities through federal funding or USDOT approval of transportation projects. In order for Section 4(f) to apply to a property, there must be a "use" of the property. A direct use occurs when land is permanently incorporated into a transportation facility or when there is a temporary occupancy of land that is adverse to a 4(f) resource.

Section 4(f) properties that are historic are identified through the Section 106 process. The portion of the Webb Ranch on the mesa top has been determined a historic property and therefore is subject to evaluation under Section 4(f). Other historic Section 4(f) resources in the US 550 area include the Denver and Rio Grande Railroad and the Florida Farmers' Ditch. FHWA and CDOT are currently evaluating if there are other properties along the new alignments being investigated that will need to be evaluated under Section 4(f).

Preliminary alternatives being considered include the following, and are depicted in the Figure 1 from the FEIS: Alternative G Modified from the FEIS, revised Alternative G Modified that avoids a gas well, Alternative F Modified from the FEIS, Preliminary Alternative A from the FEIS, Feasibility Alternative 1B from the US 160 FEIS, additional design variations along the existing US 550 alignment (the "T" Series), the Eastern Realignment Alternative, and the Western Realignment Alternative.

The first step in the Section 4(f) process is to identify the Section 4(f) properties and the alternatives that avoid them, and determine if they are feasible and/or prudent. These alternatives will be evaluated for whether they meet purpose and need as defined in the US 160 FEIS, safety and operational issues, social, economic, or environmental impacts, disruption to communities, construction, maintenance and operational costs, and any other unique problems or unusual factors.

If it is determined that there are no prudent and/or feasible alternatives that avoid all Section 4(f) properties, a least harm analysis will be prepared including all possible planning to minimize harm. The least overall harm is determined by balancing a number of factors such as how the impacts can be mitigated, how much the property will still be harmed even after mitigation, the views of SHPO, the degree to which the alternative meets purpose and need for the project, the magnitude of impact to other environmental resources, and cost.

For more information about Section 4(f), please see