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-� Debra Bloom, P.E. City of Roseville � December 3, 2007 Page 4 Road B/Har Mar Northeast Access. Therefore, the mainline of County Road B is the dominant move and requires additional green time in order to provide the most efficient mobility of the roadway. CONCLUSIONS AND RECOMMENDATIONS Based on our review, we offer the following conclusions and recommendations for your consideration: Conclusions 1. Ramsey County guidelines require a minimum of 660 foot spacing for placement of a partial access intersection (i.e., right-in/right-out). The existing RIRO access is approximately 300 feet from Snelling Avenue. 2. As the number of access points increase along a roadway, safety degrades. In addition, increased access points reduce the mobility of the roadway and its ability to efficiently move traffic. 3. Based on the crash data, the average crash rate for this intersection is 0.68 crashes per million entering vehicles. The Twin Cities metro area average crash rate for similar type intersections is 0.70 crashes per million entering vehicles. Therefore, the study intersection crash rate is comparable to similar type intersections. 4. The Har Mar Mall RIRO access onto County Road B contributes 45 percent of the illegal u- turns that occur at the intersection of County Road B/Har Mar Northeast Access during a typical weekday from 11 a.m. to 1 p.m. and 4 p.m. to 6 p.m. These vehicles have adequate access internal to the Har Mar Mall area to the signalized intersection of County Road B/Har Mar Northeast Access to travel westbound on County Road B. 5. Based on our review of the physical characteristics of County Road B, the likelihood of vehicles '`weaving" from the RIRO access to the signalized intersection is high. The close spacing of the entrance to the eastbound left-turn bay at the adjacent signalized intersection would require a vehicle to make a relatively abrupt maneuver to access this turn lane from the RIRO access, thus, creating a"weaving" maneuver. 6. The proposed development of outlot 81 does not directly contribute vehicles destined for outlot 81 to the u-turn movement along County Road B. However, the additional traffic generated by this proposed development will have a causal effect on the traffic attempting to access the signalized intersection of County Road B/Har Mar Northeast Access from the west or north side of the mall. 7. Micro-simulation modeling results indicate that under year 2009 build conditions the queues from the County Road B/Har Mar Northeast Access intersection will extend back into (and block) the adjacent internal mall intersection (approximately 135 foot 95th percentile queue, with a 10 percent intersection block time). This indicates that the proposed development will have the potential to increase the u-turns occurring along County Road B due to its causal impact.