dbat n \ < ; k or nunc ated la n d. 3 3 
tracts in the midst of unreclaimed lands lias cost between $75 and 
$100 per acre, but these costs represent situations that would not be 
encountered in regular operations. 
In regard to costs per unit of length of drain it may be said that 
elay tile drains range in cost from about one-half cent per inch of 
inside diameter per foot of length in the smallest sizes, to about 2 
cents per inch of inside diameter per foot of length in the larger sizes. 
Hand trenching for tile up to 12 inches in diameter under ordinary 
conditions ranges in cost from 7 to 15 cents per linear foot for an 
average depth of 6 feet, while trenching in fluxible or hard material 
will run up to 25 cents per foot. Rock work would, of course, be 
higher. When sheeting is required the work will cost 50 cents per 
linear foot and upward. Machine trenching is usually cheaper, there 
having been some jobs of 5-foot trenching taken as low as 4 cents 
per linear foot. As a rule, however, machine trenching costs at 
least $1 per rod for average soils and depths. 
COOPERATIVE DRAINAGE. 
The unit cost of drainage decreases as the size of the tract increases. 
This is partly due to the fact that a system installed on a small tract 
receives water from without the boundaries of the tract, and accom- 
plishes more or less complete drainage over a considerable area. 
Furthermore, the unit costs of all materials and operations are less 
on the larger projects, and the required capacity of the drains becomes 
relatively smaller as the unit becomes larger. Economy demands 
that tracts as large as possible be handled as units, and, where the 
land is owned by a number of persons, it is necessary that some sort 
of cooperation be effected. Cooperation by mutual agreement is 
usually difficult and sometimes impossible to secure, owing to an 
unprogressive spirit among some of the landowners. However, the 
legislatures of practically all the Western States have provided laws 
by means of which cooperative work may be done. In general, 
these laws provide for the formation of drainage districts and for 
their government, prescribe their powers and privileges, and outline 
the duties of their officers. The direction of the business of a drainage 
district is in the hands of a board of drainage coinmissioners who 
are either elected by the freeholders in the district or are appointed 
by the county commissioners or the district court, depending upon 
which is the recognized authority in the matter of forming drainage 
districts. The district is granted the right of eminent domain, and 
bonds may be sold to pay for the construction work. Contracts 
may be let and provision is made for the equitable distribution of 
the cost of the w^ork. The county officers are empowered to collect 
assessments. The construction work is done under the direction of 
an engineer appointed by the commissioners. 
