DRAINAGE 153 



spread far enough apart to allow them to fall in and 

 obstruct the water. They are held in position by the 

 weight placed upon them by the surrounding earth as 

 the stones in an arch are held. 



Drainage legislation. Along with the development of 

 the theory of drainage, of drainage machinery and of 

 drainage work, there has been a development of laws 

 relating to the subject. Since the flood water and the 

 drainage water run from farm to farm, it ofttimes hap- 

 pens that one man cannot drain his land unless his 

 neighbor allows him an outlet, or, perhaps, joins with 

 him in making a system of drainage including the wet 

 lands of both farms. In other cases, numerous farms 

 are concerned in one system of drainage. A common 

 ditch may be required to carry off the water from the 

 several farms. This requires concerted action, since it 

 is unfair that one, or even several, of the number inter- 

 ested should bear the large initial expense which should 

 be shared by all who are benefited. 



Most of those states in which considerable drainage 

 is needed have devised laws under which a majority of 

 the landowners in any area needing drainage can, under 

 the law, bring about co-operation of all landowners in 

 the payment of the expense of general drains. These 

 laws are made to operate through township or county 

 officers, usually through the boards of county super- 

 visors or commissioners. Those landowners who de- 

 sire the drain may present a petition to the board, which 

 decides whether the project shall be undertaken, and, if 

 so, arranges to carry forward the work and assesses the 

 costs to the respective landowners. The law designates 

 that a certain area be surveyed, and, if it be found prac- 

 ticable, drained under the drainage law. Generally the 

 board is required to appoint viewers, and to supply them 

 with the services of a competent drainage engineer. 

 These viewers take into consideration the need of the 



