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Commitment to Public Safety Anoka County Highway Department 1440 Bunker Lake Boulevard Andover, Minnesota 55304 (763) 862-4200 www.AnokaCounty.us/highways Anoka County Highway Department 1440 Bunker Lake Boulevard Andover, Minnesota 55304 (763) 862-4200 www.AnokaCounty.us/highways Medians & Access Management Anoka County Anoka County Highway Department Access Spacing Guidelines Function Services Provided Arterial Provides the highest level of service at the greatest speed for the longest uninterrupted distance, with some degree of access control. Collector Provides a less highly developed level of service at a lower speed for shorter distances by collecting traffic from local roads and connecting them with arterials. Local Consists of all roads not defined as arterials or collectors; primarily provides access to land with little or no through movement. Roadway Type Route Speed (MPH) Intersection Spacing (Nominal(4)) Signal Spacing Private Access Full Movement Intersection Conditional Secondary Intersection Principal Arterial 50 - 55 1 mi. 1/2 mi. 1 mi. Subject to conditions for all roadway types and speeds 40 - 45 1/2 mi. 1/4 mi. 1/2 mi. < 40 1/8 mi. 300 - 660 feet(3) 1/4 mi. Arterial Expressway 50 - 55 1 mi. 1/2 mi. 1 mi. Minor Arterial 50 - 55 1/2 mi. 1/4 mi. 1/2 mi. 40 - 45 1/4 mi. 1/8 mi. 1/4 mi. <40 1/8 mi. 300 - 660 feet(3) 1/4 mi. Collector and Local 50 - 55 1/2 mi. 1/4 mi. 1/2 mi. 40 - 45 1/8 mi. N/A 1/4 mi. <40 1/8 mi. 300 - 660 feet(3) 1/8 mi. Specific Access Plan By adopted plan/agreement/covenant on land ---PAGE BREAK--- How is access determined? Anoka County has implemented Access Spacing Guidelines to determine the best location for median openings. Limiting the number of openings is vital to reducing crashes and efficiently controlling traffic flow. Implementation of the spacing guidelines is a means for consistency in highway design and the development review process for Anoka County. Under most circumstances, to accommodate traffic flow in the most efficient manner, there should be no less than ½ mile between intersections with traffic signals and ¼ mile between intersections without traffic signals. While criteria can vary depending on the speed and type of roadway, these distances are widely accepted as proven engineering practices throughout the industry. The guidelines minimize delays caused by having too many traffic signals or uncontrolled intersections (intersections where no signal is present). For specifics, see the Anoka County Highway Department Access Spacing Guidelines table on the previous page. Have you ever been stopped by one traffic signal, then given the green light only to be stopped by another signal just down the road? Or, has a vehicle in front of you slowed to make a left turn, causing you to stop? These situations are frequently experienced by Anoka County drivers. The highways of Anoka County constitute a valuable resource and major public investment. It is essential to operate them safely and efficiently by managing the access to and from adjoining property. Research indicates that medians are an effective way to control access along highways. Why are medians needed? Medians improve safety by reducing conflicting traffic movements along roadways while preserving efficient traffic flow. Medians also create safer access points for adjacent property owners and businesses. According to the Federal Highway Administration, nearly 70% of two vehicle crashes on county roads that occur at driveways involve left turns. Medians are an effective method of reducing crashes and managing the flow of traffic. Conflicts at a typical intersection How will a median affect access? A common concern for property owners regarding the raised medians is how vehicles will enter or exit their driveway. With raised medians installed, access to property will be accommodated by a right turn in and right turn out access point. If a driver wishes to travel in the opposite direction, the driver will exit the driveway by making a right turn, followed by a u-turn at the next acceptable intersection. With increased traffic congestion, often a right turn followed by a u-turn will be more efficient than a left turn across multiple lanes of traffic from a through lane. Additionally, u-turns from protected left turn lanes are significantly safer than left turns across multiple lanes. The Universities of South Florida and Kentucky conducted extensive studies on the safety and efficiency of a right turn movement followed by a u-turn. The studies found that the use of median u-turns increased intersection capacity and decreased the rate of crashes up to 30%. How will a median impact business? A study was conducted by Texas A&M University to determine the economic impacts of raised medians. A key finding of the study showed customers rated customer service, product quality and product price above accessibility. The research team asked business owners and managers to indicate whether construction of a median caused elements such as congestion, safety, access, business opportunities, customer satisfaction, and delivery convenience to become better, worse, or remain the same. Overall, the majority of respondents rated any given item either better or the same. When are medians installed? Anoka County will usually construct medians in the following circumstances: New or reconstructed four lane road corridors with posted speeds of 45 mph and above. New or reconstructed six lane roads. New or reconstructed two or four lane intersections (any speed limit) with a history of significant crash rates or an expected high crash rate due to increased traffic or changed land use. Existing two or four lane county road corridors (any speed limit) with a history of significant crash rates due to direct access issues. For additional information, visit: www.AnokaCounty.us/highways Carpools * Vanpools * Transit [PHONE REDACTED] Brochure Produced by: