plan for 3 eras
The route I am currently working on (getting close to "complete") is the Southern Pacific from Portland to Albany, plus the Tillamook branch to the coast. It is set in November of 1954, so steam is still around though no longer the king of the rails, as first generation diesels tend to get the important trains.
SP's Cascade is still running, hooking up with the Northern Pacific to run this train from Seattle to San Francisco. An SP local from Portland to Eugene still runs daily and makes stops at the smaller depots the Cascade bypasses (Clackamas, Oregon City, Canby, Woodburn and Fairgrounds).
Timber is still the principal industry, reflected in my two logging camps, a log dump, three sawmills, one pulp mill and two paper mills. And with us near the end of the harvest season, the silos of Woodburn and Canby are bursting at the seams, keeping boxcars running between them and the flour mill and brewery in Salem's industrial district.
Produce from California is a year-round enterprise, and Pacific Fruit Express reefer trains are a regular sight. A mix of ice-cooled and mechanical reefers will be part of this train, and an icing platform next to the fruit warehouse in the midst of Brooklyn Yard is kept relatively busy. The fruit comes north to Portland, then sent back down south to Woodburn and Salem and their two canneries.
But once I have this layout finished to my satisfaction, I plan on altering it (and saving it with a different name), moving up the timeline to November, 1975. By then, boxcars have been replaced by covered hoppers to haul grain. Passenger locals have been discontinued, so the small depots mentioned before are closed and abandoned, as are the freighthouses, as LCL traffic has shifted to trucks. Amtrak takes over the Cascade.
Logging flats will be less common, as trucks invade that industry as well. One of the sawmills will be closed, but the other two will be larger, as big entities begin to absorb the smaller mills. The icing platform will be gone, as all reefers are now mechanical.
Urban sprawl will be evident, as many of the trees that surround the Publisher's Paper mill in Oregon City get replaced by buildings, and much of the open countryside will become part of cities that are growing closer together. (The Tillamook Branch will be the exception, as many of the towns along this route shrink as outdated industries take their toll.) Interstate 5 will become a bigger presence, rather than just a curiosity. Trailers on flat cars will become the first signs of the intermodal industry.
Once that is complete, I plan on a third session, with a date that is less a lock, November 1996-present. This will allow me to run today's motive power, big Dash 8's and 9's. Sadly the SP will be gone, and UP engines will be the common sight in Brooklyn Yard. But with the pooling and lease agreements of today, I can also run engines from RRs nowhere close to my locale, such as CSX, Norfolk Southern, ConRail or Kansas City Southern.
Container yards will be the new huge industry, although the sawmills will still be in full swing. But intermodal will become a huge piece of railroading on my layout, just as they have in real life.
Some of the small depots that were closed will be moved and reopened as a new light rail electric system gets laid. Commuter trains will be constant runners in three-hour spans in both morning and evening. Many of the "Mom and Pop" stores will be replaced with superstores like Wal-Mart, Petco and others. 7-Eleven stores and modern day gas station/convenience store/fast food joint combos will become commonplace. Publishers Paper in Oregon City will now be fully engulfed by urban spread, forcing all work to nighttime duty to keep roads from being blocked during high-traffic hours. The Port of Portland, a near non-entity in '54, will be a HUGE source of rail traffic, with grain and lumber export, barite ore transfers, Japanese auto imports, and containers, containers, containers.
All three eras have something that appeal to me. For the 50's, it's the still present iron horses of steam, plus skeleton logging flats, ice-cooled reefers, declining but still alive passenger service, small towns between the big cities, and the caboose.
For the 70's: covered hoppers, second generation diesels, muscle cars, and piggyback flats (if I can ever find any on DLS)
For the 90's and beyond: Centerbeam flats, intermodal, motive power from all over, a busy Port of Portland, light rail commuter traffic