When a solution is unknown, a feasibility study is performed to determine possible alternatives and their viability. A feasibility study is part of the Planning phase of the project development process and is intended for limited project development. Feasibility studies establish design concepts, general ROW requirements, and associated project impacts. The typical elements of a feasibility study include evaluating alternative project solutions/concepts, analyzing current and future traffic, evaluating potential environmental red flags and fatal flaws, and developing planning-level cost estimates.