Project Examples

Least Overall Harm Example

In the following example the State DOT seeks to balance minimization of impacts to a local stream, its wetlands, and floodplain while considering two similar Section 4(f) properties on either side of the existing alignment in the same area.

Overview/Purpose and Need

A project is proposed to improve safety conditions and traffic operations for vehicle, pedestrian, and bicycle traffic along the Smithville Pike where it crosses Knob Creek. In order to address a significant crash rate on this section of Smithville Pike and resolve conflicts with cyclists, the State DOT proposes to widen the lanes, add shoulders and bike lanes, and replace the narrow bridge. Although the road itself is not considered historic, Smithville Pike crosses Knob Creek, which is flanked by two Section 4(f) properties, both historic sites, and is located near the boundary of a regionally important Civil War battlefield.

Eden Farms, on the west side of Smithville Pike, consists of an impressive neo-classical mansion and several outbuildings overlooking nearby Knob Creek Battlefield to the west. Wounded soldiers from the battle were taken to Eden Farms for medical treatment during the battle. The property is listed on the National Register of Historic Places (NRHP) because of criteria A (association with historical event) and C (architecture).

The Marble property, on the opposite side of the creek and east of the road, is a farmstead consisting of a Federal period brick dwelling that is surrounded by an eclectic mix of outbuildings dating from the ante-bellum period to the present. These outbuildings include several barns, a cook house, and a guest house. The Marble property has no known association with the Knob Creek Battle other than possible incidental movement of troops across the property. The property is eligible for listing on the NRHP for its architecture (criteria C).

Challenge

The avoidance alternative generally follows the existing center line of the Smithville Pike, with a minor shift to the east of Eden Farms and to the west of the Marble property. However, even though this alternative would completely avoid both of the historic sites, it presents several problems. A new Knob Creek crossing would have to be constructed in the same location as the existing bridge, requiring demolition of the old bridge and substantial detours on County roads. The detours would be approximately three miles in length and require costly interim improvements to the County roads, including additional lanes and expanded intersections. The pavements would have to be completely reconstructed because of the diversion of numerous heavy trucks that would otherwise use Smithville Pike. The need to accommodate heavy truck traffic not only adds substantially to the detour costs, but has been opposed by the majority of residents in the area that adjoins the detour route because of safety concerns, increased traffic, and potential conflicts with elementary and middle schools along the detour route.

In addition to these issues, the Section 4(f) avoidance option presents serious environmental concerns among the U.S. Army Corps of Engineers (USACE), the Environmental Protection Agency (EPA), and the State Department of Natural Resources (DNR). Specifically, agency officials raised questions about the level of impacts to Knob Creek and its associated riparian wetlands and floodplain, including a longitudinal encroachment upon the floodplain. While everyone agreed that there appeared to be no practical way to avoid stream and wetland/floodplain impacts entirely, there was a general consensus that impacts resulting from this avoidance option would be substantial in this flood prone area.

Given the collective impacts of the factors detailed, FHWA determines that total avoidance, while feasible, is not prudent. This decision is justified because of increased construction and maintenance costs for detours that would be temporary only, severe disruption to established communities and schools along the detour route, and severe environmental impacts to Knob Creek, its associated wetlands, and floodplain.

In response to these concerns, the State DOT developed two more options. The first – Option A – is a shift of Smithville Pike to the west which minimizes impacts to Knob Creek and its wetlands and floodplain as a result of a more transverse crossing. Land would be required from a corner of Eden Farms resulting in an adverse effect because of the land acquisition and the loss of two outbuildings. The Marble property would be avoided, and a costly detour would not be needed.

The second – Option B – involves a shift to the east that encroaches upon the Marble property; only land will be taken from a portion of the property farthest from the main residence. The impacts to Knob Creek, its wetlands and floodplain are almost identical to those that would be caused by the Section 4(f) avoidance alternative, only they would be on the opposite side of the stream. Eden Farms will be avoided, and a costly detour will not be needed.

Least Harm Analysis

Since total avoidance of Section 4(f) properties in the study area has been determined not to be feasible and prudent, an analysis of the remaining options is required to determine which results in least overall harm.

Option A – This option involves a shift of Smithville Pike to the west which minimizes impacts to Knob Creek, its wetlands, and floodplain. Land would be required from a corner of Eden Farms resulting in the loss of two outbuildings, an adverse effect. The Marble property would be avoided, and a costly detour avoided.

Option B – This option involves a shift to the east that encroaches upon the Marble property; only land would be taken from a portion of the property farthest from the main residence. The impacts to the Creek, its wetlands, and floodplain are almost identical to those that would be caused by the Section 4(f) avoidance alternative, only they would be on the opposite side of the stream. Eden Farms would be avoided, and a costly detour will not be needed.

Analysis – In balancing the impacts that would be caused by both options, FHWA has to consider multiple factors regarding both Section 4(f) properties and non-Section 4(f) properties. For instance, Eden Farms is considered the more important of the two historic sites because of its association with the Knob Creek Battlefield and greater historic integrity. But Option B – which avoids Eden Farms – results in greater impacts to the creek, its wetlands, and floodplain. FHWA also has to consider the magnitude of remaining harm, after reasonable mitigation, to all the resources, both Section 4(f) and non-Section 4(f) properties.

Determination – After balancing all the factors, FHWA concludes that Option A would have least overall harm even though it has slightly greater impacts to a Section 4(f) property. The mitigation plan for this project includes relocation of the two outbuildings to other portions of Eden Farms, provision of parking area near the creek with a plaque interpreting the battle, and construction techniques to further minimize impacts to remaining buildings and the creek.