Prototype Information
In 4.1.1.4 Drainage I discussed that the most important feature of economic maintenance is the proper drainage of the track and the entire roadway. The worst enemy of the roadbed is water, and the farther it can be kept away, or the sooner it can be diverted from the roadbed, the better the track will be protected.
Drainage of the roadway is effected by providing (1) ditches, (2) drains, and (3) culverts. To be serviceable under all conditions ditches, drains and culverts must be sized to handle the water expectations, and be secure in foundation and end construction against washing out.
One of the prototype freelanced sections
of my railroad is Preachers Slough, a station on the joint Milwaukee
Road / Union Pacific line in the Montesano area (mile post 83). In that
one mile stretch around Preachers Slough there were (in order east to
west):
- A 64' long 3 1/2" x 4" Timber Culvert,
- A 57' long 18" Corrugated Pipe,
- A 57' long 3' x 3' Timber Culvert,
- A 75' long 8" Corrugated Pipe,
- A 60' long 8" Corrugated Pipe,
- A 16' long 1' x 1' Timber Culvert,
- A 45' long 2 1/2' x 3' Timber Culvert,
- A 20' long 12" Corrugated Pipe,
- A 12' long 1' x 1' Timber Culvert,
- A 16' long 1' x 1' Timber Culvert, and
- A 55' long 24" Corrugated Pipe.
There was only one instance of Wrought Iron Pipe used on that branch. A 30' long 6" Wrought Iron Pipe was located at MP 79 on the branch line.
The WWSL
The WWSL follows the joint line Milwaukee / Union Pacific MOW ditch, drain, and culvert philosophy of "quickly and cheaply built". It is undoubtedly economical for a Class 3 railroad.
When available the WWSL follows the Union Pacific Common Standard for most roadway situations. Other railroad common standards may be used or referenced to 'fill in the engineering blanks' when there is no UP Common Standard available.
The following pages cover WWSL drainage construction projects:
- Ditches. The
appropriate ditch standard for roadbeds is found on the roadbed
engineering diagram. Intercepting ditches are constructed when WWSL
landforms are laid out and constructed.4.1.8.1 Side Ditch
4.1.8.2 Ditch between parallel tracks
4.1.8.3 Intercepting Ditch
Drains. There are three types of drains, box drains, surface drains and french drains. See the following pages for additional information and and construction details.
4.1.8.6 French Drains
- Culverts. A culvert is an opening through the roadbed with a depth of roadbed over it. There are four basic types of culverts, Open, Pipe, Box and Arch.
Reference
Pennsylvania Railroad Common Standard
Preachers Slough Track Chart
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