44 REPORT OF OFFICE OF EXPERIMENT STATIONS. 



different States and Territories during the year by engineers of the 

 office, some of the work being done in cooperation with local interests 

 which contributed a part of the expense. 



The chief of drainage investigations directs a regular staff' of 25 

 office and field engineers and 2 draftsmen. The entire time of one 

 engineer is given to the work of tile drainage in various parts of the 

 humid region where special information and advice upon that subject 

 are needed, and five are stationed in the Western States to. study the 

 problems which arise in attempts to drain irrigated lands and to 

 assist the owners Avho desire to reclaim tracts which have become 

 injured by seepage or by alkali. Other field engineers are employed 

 in examining and reporting nj^on the status of drainage in various 

 localities, such examinations being made upon special requests which 

 are filed from time to time with the office, Thev are also charged 

 with the duty of advising engineers, farmers, and others regarding 

 the best practice in drainage, of collecting practical and technical 

 data pertaining to methods of reclaiming land, of giving assistance 

 to land owners in the organization of drainage districts, and of sug- 

 gesting preliminary plans for reclaiming areas of farm lands or those 

 subject to j)eriodical overfloAv, all of which may be made useful for 

 agriculture. The office engineers reph^ to inquiries received by mail 

 concerning perplexing drainage problems. They also examine plans 

 which are transmitted by mail or in person, and in many instances 

 suggest improvements or modifications which are of great value. 

 They review, check, and edit the reports jDrepared by the field engi- 

 neers upon the various projects which they have worked out, and dis- 

 seminate as far as practicable the information obtained by the entire 

 staff of engineers. 



Some of the special problems encountered in farm drainage are 

 the rate of percolation of water through heavy, compact soils, such 

 as buckshot and river-bottom silts, the proper drainage and conser- 

 vation of moisture in peat and muck soils, the comparative value 

 and econom}^ of large tile drains as compared with open ditches under 

 the A'arious conditions of soil and of agricultural development, and 

 the best and cheapest methods of constructing small ditches for water- 

 courses and digging trenches for tile drains. 



Problems connected with the drainage of iiTigat^d land require 

 a careful study of the movement of the ground water in order to 

 develop practical and efficient methods of restoring injured lands to 

 their former value for cropping purposes. Thorough investigations 

 show that in some instances a single drain may intercept the under- 

 flow and prove efficient. In others it is found that several drains are 

 required to properly reclaim the injured fields. The accumulation 

 of alkali which results from seepage in many localities is a serious 

 menace but is removed by draining the land which shows injur}' of 



