mile (in the case of jumps, 500 or more), and the territory can be added to the UA.
As with jumps and nonresidential urban land uses, undevelopable territory also is used in some cases to link an outlying cluster of densely settled territory to the main body of the UA. The Census Bureau designates territory as undevelopable only if it consists of water area, mud flats, swamps, marshlands, steep slopes, and other terrain where development is nonexistent and new development is virtually impossible because of the physical limitations; such territory must not contain any existing housing or commercial structures.[1] There must be a road connection from the main body of the UA through the undevelopable territory to the outlying densely settled area, and the road distance cannot exceed five miles.
Indentations occur where a low-density census block or cluster of blocks protrudes into the main body of the UA. Indentations almost always consist of territory outside of any place (only very rarely are they small incorporated places or CDPs). Indentations formed by the boundaries of incorporated places usually occur more frequently than those involving only territory outside of any place. The inclusion of indentations smooths the UA boundary, gives it a more regular appearance, and simplifies its presentation on maps.
The Census Bureau includes an indentation in the UA if it is:
- Flanked by territory that has an average density of at least 1,000 inhabitants per square mile.
- Less than one mile wide across its open end.
- At least two times deeper than it is wide.
- Five square miles or less in size.
- Closeable by means of a block boundary located across or close to its open end.[2]
All of the above conditions must apply.
Notes and References
- ↑ Local zoning classifications of land as undevelopable are not sufficient to qualify territory as undevelopable under the Census Bureau’s criteria because such classifications are subject to change at any time.
- ↑ Often the census block boundary across or close to the open end of an indentation either curves inward or bulges outward. The indentation is closeable if this area of bulge or sag is less than 20 percent of the indentation’s ideal area. An indentation’s ideal area is defined by the projection of a straight-line boundary across its open end; this line also measures the indentation’s width. The measurement of depth always begins at the center of this line, follows the main channel of the indentation, and ends at its deepest point.
Urban and Rural Classifications12-9
