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6 For a complete listing of the states that responded to stripe the road. However, staff believed that a safety the survey and their responses, see attached Appendi- study of the road done in the future would prove that ces B and C. the changes were beneficial to the overall safety of the road. B. Application of Context Sensitive Design Florida--Cost considerations and safety were high- Responding states provided examples of CSD success lighted when the designer used the analysis found in stories in their survey responses. Generally speaking, the recently published Highway Safety Manual.11 Using environmental, safety, historical, and cost aspects and that analysis, the designers were able to demonstrate impacts of the project are considered in the planning that a divided highway with a median was much safer phase of the project. The public is involved in the proc- than a four-lane road with a two-way, left-turn lane. ess, which ensures more buy-in for the project because The analysis demonstrated an improvement in the their input is considered. For the purposes of this di- safety of the corridor and saved the cost of the purchase gest, because many agencies must defend against per- of additional right-of-way. sonal injury claims on the premise that a road is rea- Maryland--When considering the I-695 bridge re- sonably safe, focus herein is on the steps taken by placement, the department decided to reduce the advi- designers to ensure flexible designs did not compromise sory speed on one of the ramps because the ramp that the safety of the system. It should be noted, however, was called for in the plans did not meet the American that there are many examples of flexible design that do Association of State Highway and Transportation Offi- not focus on safety; they focus on maintaining the char- cials (AASHTO) radius requirement. Safety improve- acter of the road, preserving important historical land- ments that were used to mitigate the reduction in- marks, or reducing environmental impacts. cluded adding signing and lighting along the ramps, adding a traffic barrier, removing existing vegetation to Delaware--One state road corridor was in need of improve sight distance, and making geometric im- improvement for more than 30 years. The community provements. While the bridge ramp does not meet the did not want the four-lane roadway that the Delaware AASHTO standard, staff is confident that the ramp is Department of Transportation (DelDOT) had proposed reasonably safe. Staff who responded to the survey in- because they wanted to retain their "small town" at- dicated that the design exception file and milestone mosphere. The DelDOT Needs Analysis identified four reports are kept indefinitely and that those documents basic needs--reduction of congestion, safety improve- adequately document the mitigation strategies and de- ment, establishment of defined entrances, and im- cision process used. Those documents show the agency's provement of existing roadway conditions. Since the deliberative process and explain the reasons that the community was unwilling to accept a widening of the generally-accepted standards could not reasonably be road, the state studied the amount and type of accidents achieved. in the corridor and determined that the accident and Washington--The I-90 Snoqualmie Pass East cor- safety problem could be addressed by providing center ridor is located in Kittitas County within the We- turn lanes and right-turn lanes at intersections. To ad- natchee National Forest. The highway was upgraded dress the problem of vehicles leaving the road and strik- from two to three lanes in each direction. Problems in- ing fixed objects, such objects were moved outside the cluded road closure due to avalanches, which were ad- clear zone. The addition of safety grading and travers- dressed by construction of snow retention fences and a able slopes provided the recommended recovery area for snow shed to protect the roadway from avalanche errant vehicles. Design exceptions were obtained for a chutes, accidents involving wildlife, and the existence of reduced-width center turn lane, and the above-noted six curves that did not meet minimum design standards mitigation steps were taken to accomplish the goals of for the posted speed. Wildlife crossings were expanded minimizing impacts to residences and businesses, con- and portions of the alignment were straightened. To trolling cost, and improving overall safety. accommodate environmental concerns and the moun- Colorado--Glenwood Canyon on I-70 was built in tainous terrain, reduced median and shoulder widths an environmentally-sensitive area. Compound curves were used. To mitigate the narrower lanes and median were used where other alignments could not accommo- widths, high-performance barriers and rumble strips date the environmental features of the canyon and an were used. existing power plant. The widths of the highway lanes were originally 4 ft, 12 ft, and 12 ft, with 6-ft outside C. Documentation Use in Litigation shoulders. When the highway was repaved recently, it The states were asked whether documentation that was restriped as 4 ft, 11 ft, and 11 ft, with 8-ft shoul- they had gathered during the design process was useful ders because the 6-ft shoulders were causing problems in later defending the state in court or against legal for broken-down vehicles that had no safe refuge. Hav- challenges. Fifteen of the 28 states (53 percent) re- ing 11-ft lanes is not standard on Interstate highways sponded that they had used documentation of the deci- but it was considered to be a safety improvement to have 11-ft lanes and an 8-ft breakdown shoulder. Sur- 11 Survey Response, Florida, Mar. 2011. See Florida High- vey results indicated that Colorado DOT did not have way Safety Manual, available at http://www.flhsmv.gov/fhp/ documentation or analysis of the initial decision to re- Manuals/.