Show CONCRETE GOMES COMES INTO USE Ir IN M MAKING KING CANAl GAES Although Costlier New Material Material Material Ma Ma- Will Wil Take the Place of Wood Most of the gate structures in American Ameri Amen can irrigation canals a few years ago were of wood but more recently concrete concrete con con- crete both plain and reinforced has come como into common use Wood hns has the tho advantage of cheapness and anel of oL of easy hand handling and the fhe disadvantage e of at rapid depreciation ns while concrete w which ich lies has t the tho e advantage of permanence is more moro costly costy The kind of ot material used mod ae as well wel welS as S other ether features of gate ate structures varies in different iri irrigated rc regions ions of the tho West One Ono section often used features especially adapted to it of which other sections that could use uso them equal equally el well are ignorant The United States department of agriculture is endeavoring endeavor in lug ing to briD bring together to such designs for gato gate structures as are a adapted apt d to mau many so that each locality may Jar profit by bJ the tho practices o of 01 others and has just issued a ne new bulletin Xo No 15 entitled Gato Gate Structures for Iiri litigation Irrigation aton Canals intended to be of assistance to cD engineers and others with wih technical technical knowledge of the subject The purpose of ot all al the tho gates ates considered consid ered creil in the new bulletin is the control of ot the flow fow of water in the ditches or canal cacal s systems and floodgates flood food gates regulate the tho water entering the system from the source of supply lJ check gates regulate tho the water while wit within bin the and waste gates ates control the tho water which is to be turned out and wasted i and branch canal lateral and gates re regulate ulato tho the water turned i iV V w u- u out to branches of tho the system or to users Of Of General Interest Small Smal and medium sized structures are for the most part described in the new bulletin as it is believed ed bele that most of the problems confronting the engineer engi cog neer located in isolated regions of the West relate to this class The bulletin should also be of value to o o directors of mutual water companies who are themselves irrigators and who are arc called caled upon to pass upon questions of construction construe construe- tion and maintenance On One of the important questions dealt deal with wih is that of the materials to be used for gate structures Shall the they ate be of wood or concrete te The best practice according to the departmEnts departments department's departments department's depart depart- ments ment's mEnts mEnt's investigator seems to bo be to tomake tomake tomake make a structure of combined wood and concrete using concrete for the parts that that are aro inaccessible and not casU easily replaced and wood for the tho accessible ac at- parts which can an bo be replaced easily Local conditions affecting the relative prices of these materials will vili wi also help to determine which material should be ce used New Plan lan Because of tho the hi high h cO cost t of water I rights right and the inability y of settlers setters to tomake tomake make the payments required there is much to be said in favor of the cheap cheaper er woo wooden en structures for ori original nal construction con con- with a n view to their replacement replace replace- ment meat with wih more permanent structures structures- structures of concrete as the oM decays This Thi wi will lessen the first cost and nd will wi bring brinK tho the hen heavier viel cost after the lands have ha c been put under cultivation The Tha use of wood has bas the further advantage advantage ad ad- vantage that in case ease of mistakes ac in either tho h typo of ot structure or the tho location location lo 10 cation it is i not so cost costly It frequently frequent frequent- ly happens that structures arc are found I to be placed paced too high or too low lot or ori orthey orthey i tho they are too small smal and not of the best type A few years years' experience ence in their operation will wi demonstrate the these e facts a alter after which a mere Jere permanent structure ture tune of wood or concrete may maj be put in Howe er if the failure of a structure ture will wi result immediately in great groat damage e to the tho canal system or to crops only the most nearly permanent con con- sti should bould bo ho used at first If I tho the failure merel merely means the replacement replace replace- ment meat of the structure itself the cheaper cheap er or construction may Jay profitably be put in iii first The bulletin may be had free ar ae long as tho the departments department's supply lasts b by those who may mi find it profitable 1 I use UC I |