A River Road (kbc) or Valley Road / Valley Type Road (kbc) is a roadway or route that runs through the valley of a relatively large natural waterway, using the valley as a means to maintain a fairly level and direct route.
To meet this designation, the river valley should be large enough, and be differentiated enough from the surrounding terrain, so that the valley has a distinctive advantage as a route - e.g., a mature-stage valley, where the valley is more than about 1/4 mile wide, has distinctive valley walls, and fairly dissected uplands beyond. Streams in valleys this size also tend to be navigable for a canoe, at the minimum.* Two basic variants exist, the Bank Route and Terrace Route. Easier to determine typology than upland routes.
Most(?) Valley Routes are Bluffside...and by nature, parallel to the waterway and valley. (An exception is the iffy [Transverse Sprint] Route Type.)
Exemplia Gratia:
The Bank Route Type (kbc) runs on the valley floor / valley flat immediately along the river / stream / waterway, as much as possible abutting the riverbank. It stays as close as possible to the river without running through frequently flooded areas, sloughs, outwash etc. It swerves inland to cross tributaries at ideal locations, where a tributaryıs bed is stable and not too wide. A natural levee along the bank, however slight, is an ideal location. This placement is probably due to two concerns:
Exemplia Gratia:
The Terrace Route Type (kbc) runs parallel to the river and the valley's course, but usually at a distance from the river and on the less-frequently flooded terraces. It also usually runs along a terrace bluff, on the upper edge (q.v. Bluff Route or Bluff Edge / Terrace Edge). The typical variation is the Mid-Valley Route.
The Mid-Valley Terrace Route Subtype (kbc) runs through the valley floor usually at or near the mid point between the waterway and the valley wall. A mid-point position places transportation in a central position in the tillable land, equalizing the distance to the far ends of the fields at the waterway and valley walls. The mid-point may be the ideal position that compromises being as close as possible to the waterway, while avoiding many floods. As such it is usually on the upper edge of a middle or upper valley terrace.
It may also avoid sloughs, deltas and swampy areas that are close to the valley walls. It may be more direct since the terrain is smoother than the valley wall, and less amorphous than the river bank. A mid-point placement may also be on the tangent in a curve of the valley, i.e. the shortest route from one stream bend to the next.
Exemplia Gratia:
Ideal crossing points or fords on a meandering river may be where the river has a straight stretch running perpendicular across the valley, and the Mid-Valley route road placement compensates for that.
The Break-of-Slope Route Type (kbc) runs at the change of slope between the level valley floor and steeper valley walls. Its placement can be seen two ways:
Historically, the value of tillable land generally outweighed a level, easily maintained route, and thus some Break-of-Slope Route roads are more on the slope than the terrace. The results are swerving routes, cuts into toe slopes, fills across tributary valleys and gulleys, outwash cones and meltwater invading the roadway, and short steep rises and dips. Most Valley Roads in small valleys tend to be this type since the tillable land is at even more of a premium than in a larger valley.
Exemplia Gratia:
The Transverse Sprint Route Type runs perpendicular to the valley, within the valley. It is usually a connector between parallel Valley Routes, such as a Bankside Route and a Break-of-Slope Route.
This category may not belong in the Valley Route Supertype, since it is diametrically different from the other Valley Route types (other than its location in a valley). It is not quite a route element, since examples tend to be longer than a stone's throw...
Exemplia Gratia:
The Bluff Edge / Bluffside Route runs atop high upper terraces, usually (in South Central Ohio) on Wisconsinan-age ground moraines along or in major valleys, or Illinoan-age glacial outwash terraces. The route tends to be along the edge of the bluff / highbank, but it need not be there.
(Is this an Upland Route Type or Valley Route Type? Is it both and neither, transitional, and thus deserves its own Type?)
Exemplia Gratia:
Route connecting nearby navigable ends of two waterways. This is usually perpendicular to any ridge. Perhaps with less restrictive name, can embrace any path connecting headwaters...
Is this an Upland Route Type or Valley Route Type? In some cases the portage route is level or rolling (e.g. Miami-Maumee, Cuyahoga-Tuscarawas) but sometimes it is hilly (e.g. Ottowa River-Lake Huron (Canada), Pennsylvania routes). Is it both and neither, transitional, and thus deserves its own Type?
Exemplia Gratia:
Runs on upland terrain; i.e., not on level or fairly level valley floors.
These route types are more reflective of much terrain control over route placement and design/evolution. This was allowed/tolerated because of the technological ability of the culture and/or priority of the route:
Perhaps two versions of each are necessary, depending on the coarseness / fineness of the terrain:
Exemplia Gratia:
Exemplia Gratia:
Two main variants:
Exemplia Gratia:
Exemplia Gratia:
Two main variants:
Exemplia Gratia:
Exemplia Gratia:
Routes that run along other routes or atop (replacing) other route structures...
(Access roads that run alongside modern suburban roads or superhighways are excluded; they are modern engineered routes the belong elsewhere...)
Semi-engineered route - but not because the route itself is engineered. This is a result of canal construction: The canal is designed to conform to the terrain, with some earthmoving. Since the canal assumes superiority in transportation, any nearby roughly parallel road is realigned to be adjacent to the canal right-of-way. This eliminates landlocked parcels, where usable land would be trapped between the two transportation structures.
Similar to "access road" created with modern highway or arterial street redesigning.
Exemplia Gratia:
The abandoned canal prism and towpath are modified and reused as a road, obliterating the canal structure but generally preserving its route.
This is not the same as realigning the road alongside the canal structure, but it is usually a realignement of a road that had already undergone that readjustment 70-80 years before.
Exemplia Gratia:
Same as above, but with a railroad, instead of a canal: Semi-engineered route - but not because the route itself is engineered. This is a result of railroad construction: The railroad is designed to conform to the terrain, with some earthmoving (more than the canal). Since the railroad assumes superiority in transportation, any nearby roughly parallel road is realigned to be adjacent to the railroad right-of-way. This eliminates landlocked parcels, where usable land would be trapped between the two transportation structures.
Similar to "access road" created with modern highway or arterial street redesigning.
Exemplia Gratia:
The abandoned railroad bed is modified and reused as a road. This is not the same as realigning the road alongside the railroad structure.
Exemplia Gratia:
Same as above, but with a road, instead of a canal or railroad: This is a result of (rarely) canal or (more often) railroad construction in level land, where an existing road already conforms to the terrain, or there is not enough terrain to conform to, and the road is going in the right direction.
In this case, little earthmoving is needed for the more terrain-sensitive canal or railroad, and so the new canal or railroadis aligned to be adjacent to the road right-of-way. This eliminates landlocked parcels, where usable land would be trapped between the two transportation structures. More importantly, it allows interconnection between the two transpoortation structures such as depots or transfer stations.
It is not always clear which came first though; investigation into histories may be needed to be sure.
Exemplia Gratia:
Same as above, but with two railroads, instead of a canal or railroad and road: This is a result of a later railroad following in the footsteps of an earlier railroad. It occurs in level to hilly terrain, as long as the two railroads have the same short-term destination.
Exemplia Gratia:
Result of federal (and sometimes state) land survey grid - usually one-mile sections, often quartered. Aligned to cardinal directions, specifically magnetic or astronomical north.
Roads based on land survey usually disregard terrain, though the rougher the terrain, the more the roads must confom to terrain regardless of the land survey.
Where section lines don't quite match up, different road intersections are often formed; see Route Elements.
Road aligned to section-line grid.
Road aligned to grid of quarter-section, those bisecting each section two ways (resulting in quadrants).
Exemplia Gratia:
Straight route across level terrain - thus "across" the level land.
Often found on Valley Terraces.
Straight route across gently rolling terrain - thus "over" the hilly land.
Often found on rolling Uplands.
"Transp - Route Typol 2.html" v1.6.1 - 10/25/02, 7/19/02
Intrepid Historical Services - Kevin B. Coleman - Columbus, Ohio, USA
(Adapted 06/23/02 in part from "Route Types - A Suggested Typology" v 4.1 -
Second Draft: August 17, 1999 - Original: May 21, 1998