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B..Rw_ ..................................... <br /> <br />DAMES & MOORE GROGP COMPANy <br /> <br />MEMORANDUM <br /> <br />BRW <br />Thresher Square <br />700 Third Street South <br />Minneapolis, MN $5415 <br />Phone: (612) 370-0700 <br />Fax: (612) 370-1378 <br /> <br />To: Tim Yantos <br />From: David Mahle <br /> <br />Copy: Dan Meyers File: <br /> <br />33935-001-0702 <br /> <br />Date: <br /> <br />Subject: <br /> <br />December 3, 1998 <br /> <br />NCDA/BNSF Line Capacity Simulation Results <br /> <br />Line capacity simulations have been performed by BNSF, using the Dispatch Planning Model, to <br />determine the amount of additional trackage and signaling that will be required to support <br />commuter rail operations while maintaining the level of freight service that is expected to exist in <br />the startup year 2003. To do this BNSF first developed a base case with 2003 expected traffic <br />levels and operational changes. Commuter service was then started on the system and various <br />capacity improvements were added to gauge their effect. The simulation does not give an optimal <br />answer automatically but rather is used in a series of iterations to determine impacts of <br />combinations of capacity improvements. <br /> <br />There are two primary statistical measures that are used by BNSF to determine the impacts of <br />capacity improvements. The first is freight transit time per 100 miles. This measure indicates by <br />train class and for all freight trains the time required by a train to go 100 miles. It includes actual <br />running time, delays due to congestion and meeting other trains, and dwell time at terminals. The <br />second measure is freight train delay per 100 miles. This is a component of transit time and is the <br />most important measure of congestion and lack of capacity. These measures are also developed <br />for Amtrak and commuter trains but are not important indicators as these trains have the highest <br />dispatching priority and vary little in running time or delay regardless of the number of freight <br />trains or level of congestion in the system. <br /> <br />The attached status information indicates these key measures for the 2003B base case and a <br />series of simulations with the commuter train schedules added to the system. Five different <br />combinations of upgrades are indicated together with the impact on the two key measures <br />discussed above. <br /> <br />DJM:mr <br /> <br /> <br />