Transportation System Plan 2018-2038

intersection in the 2023 PM Peak Hour SYNCHRO m odel. The factor serves to reduce the PM peak hour traffic volum es thus providing an estim ate of the level of operation during the second-highest hour. Spreadsheet tables showing the volum e reduction factor s for each intersection are included in Appendix C of the LOS Study report. Future-year Volume Prediction Methods The Metropolitan Planning Organization (MPO) Trans portation Model (EMME/2) provided by the Rogue Valley Council of Governm ents (RVCOG) and th e Oregon Departm ent of Transportation’s Transportation Planning and Analy sis Unit was used to determ ine traffic growth rates on roadway s throughout the City of Medford. The EMME/2 m odel estim ates traffic volum es on major roadway s based on estim ated population and em ployment figures, am ong other factors. In the EMME/2 m odel, the boundary of the MPO is split into large transportation analy sis zones (TAZs). All regionally significant roadway s within the MPO are included in the EMME /2 model. The EMME/2 traffic assignm ent links trips between TAZs via the m odeled roadway network. For purposes of this analy sis, 2000 and 2023 EMME/2 tr affic assignm ents were obtained. It should be noted that the 2000 m odel is not based on actual land- use in the 2000. Rather, the land-use intensities contained in the 1995 EMME/2 m odel were increased acro ss the board by five percent. In addition, the 2020 land-use data was increased by five percent to estim ate 2023 land-use data. Applicable traffic growth rates throughout the analy sis area were de termined by com paring 2000 and 2023 EMME/2 model forecasts. The resulting growth rates were applied to the balanced 2002 approach inflow and outflow volum es to arrive at future y ear volum es. In so me cases the actual difference in m odel volum es between 2000 and 2023 were used instead of apply ing growth ra tes. This m ethod is generally used when the existing traffic volum es are low or the base-y ear EMME/2 assigned volum es are significantly different than the base-y ear counted traffic volum es. In some situations the assigned EMME/2 volum es were reallocated from one roadway to another when actual or planned street connectivity would warrant such a reallocation. Future-y ear turning-m ovem ent volum es were derived from approach inflow and outflow volum es. An iterative process is used to obtain a set of intersection turning movem ent volum es that match the post- processed approach inflow and outflow volum es. The m ethod used to predict turning movem ent volum es from approach inflow and outflow volum es is describ ed in National Cooperative Research Project Report 255. In order to predict turning m ovem ent, the program first starts with a “seed” – basically an estim ate of what the resulting turning m ovem ent split for each approach should be. The turning m ovem ent seed is generally the same as the existing turning m ovem ent volum es at a particular intersection. The program starts with the seed and adjusts individual turning m ovem ent volum es up or down until the post-processed approach inflow and outflow volum es are satisfied. For facilities contained in the South Medford Interc hange Project area, data from the traffic study produced for the Environm ental Im pact Statem ent (EIS) was used. The EIS traffic study analy zed traffic operations for a “No-Build” scenario and three bu ild scenarios for 2010, 2020 and 2030. For purposes of this analy sis, the “Highland Alternative” was assum ed to be the preferred alternative. This alternative eliminates the existing interchange at Barnett Road and replaces it with a new interchange at a new roadway connecting Highland Drive (to the east of I-5) to Garfield Street (to the west of I-5). 2023 volum es were developed by inter polating between the 2020 and 2030 volum es contained in the EIS. All EMME/2 data, hand adjustm ents and future-y ear volum e forecasts are provided in Appendix D of the LOS Study report. G-6