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23 longer than 12 years; therefore, signs less than three years old dates. The county had a combination of Type I, Type III, and in an area scheduled for blanket replacement would remain Type IV sheeting materials. Based on their experience and and be monitored periodically to ensure compliance. Signs field observations, most of the Type III and Type IV signs between the installation age of four and five years would be lasted from 10 to 12 years. The agency had been committed removed, but would be used as temporary replacements if a to regular sign replacement, but admitted that there were some sign was damaged or knocked down. Type I signs that had been on the roadway for 15 to 20 years. The first step the engineer took was to continue to use dura- ble and adequate sign sheeting materials. It was believed that Method Review some of the newer Type III and Type IV sheeting still per- The town of Clifton Park acknowledged that many of the issues formed adequately; however, the Type I and many of the older that small agencies encounter such as fiscal restraints and van- signs needed to be replaced. The engineer believed that replac- dalism were similar to challenges faced by larger agencies. One ing them with new Type XI signs would be more noticeable to major difference that a small agency would have to contend for drivers during adverse weather conditions. with is the limited number of staff. This small agency needed personnel during daytime hours and experienced difficulties St. Louis County previously implemented a blanket replace- with rearranging work schedules. It was desirable to select a ment method with adequate results. The county was divided method that could easily be added to their already tight work up by townships and all signs on a segment of roadway were schedules. Also, the staff at Clifton Park was informed about typically replaced at the end of the replacement cycle based but not experienced with the minimum retroreflectivity require- on material warranty periods. The engineer simply modified ments. As a result, they sought outside assistance and advice and accelerated the existing blanket replacement schedules from local professionals who were more knowledgeable. to meet both the 2015 and 2018 compliance dates. Along with this method, the county maintained a sign inventory Ultimately, the town emphasized the importance of con- system that helped with maintenance activities and resource tinuing education and participation in professional societies. management. Through interacting and networking with other profession- als, the town was able to acquire additional funding, select an The sign inventory started as an Access database that simply appropriate course of action, and customize a computer-based documented sign information and blanket replacements. By system that would address their current and future needs. By 2005, maintenance demands quickly exceeded the capabilities sharing knowledge and expertise, this small agency was able of this system and the agency transitioned to a new program. to address the problems presented by limited staff size and The engineer acknowledged that their needs and requirements gain the benefits that a larger agency may possess. Town continued to expand and the county changed programs again officials hope to share their experiences and knowledge with in 2010. The new system was relatively inexpensive and was other small agencies at upcoming conferences. able to track and manage other roadway items. Each sign inventory system transition progressed smoothly and there were no major issues or loss of information. The engineer St. Louis County, Minnesota reported that individual sign information was checked for Background accuracy during the course of each system change allowing the agency to identify missing and unnecessary signs. St. Louis County is a large rural county in northern Minnesota that covers approximately 7,000 square miles. The 2010 cen- St. Louis County elected to continue blanket replacement sus population was approximately 200,000 residents and the because it was well-established and staff was accustomed to largest city is Duluth. The area is accustomed to dealing with the routine replacement cycles. The visual nighttime inspec- long winters and the average low temperature for the winter tion method was considered; however, it was decided that and spring is about 15F (25, 26). Average annual precipita- the county was not properly staffed to inspect such a large tion is approximately 31 in. and the average annual snowfall amount of roadway. The measured retroreflectivity method is approximately 78 in. The yearly average possibility of sun- was also quickly rejected for a similar reason. shine is 52% and the average number of cloudy days per year is 186. At the time of this report, the public works department Method Review employed seven full-time maintenance technicians who were engaged in traffic signing activities. The resident engineer esti- One of the keys to St. Louis County's approach was that mated that the county maintains approximately 40,000 signs the staff was familiar with the routine blanket replacement and approximately 3,000 centerline-miles. cycles and the sign inventory system. The primary and sec- ondary methods had worked effectively and the engineer Sign Replacement Methods did not need to implement any sizeable or hasty changes to meet the MUTCD compliance dates. Procedures were kept The county was familiar with the MUTCD retroreflectivity straightforward and consistent, which has allowed the county requirements and took proactive steps to meet the compliance to be thorough in maintenance activities and not neglect any