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information.  The  time  is  too  short  for  that,  but  rather  to  call 
forth  brief  and  pointed  discussion  on  the  various  points  presented 
by  those  who  have  devoted  thought  and  study  to  these  subjects. 
Since  the  time  when  water  was  first  taken  from  the  streams  of 
the  West  for  irrigation  purposes  up  to  the  present,  a period  of  over 
50  years,  a large  percentage  has  been  wasted  by  porous  earthen 
channels.  It  may  not  surpprise  some  of  you  to  learn  that  the 
results  of  measurements  on  73  canals  of  Western  America  by  our 
agents  show  an  average  loss  of  5^4  per  cent,  per  mile  of  ditch.  It 
is  not  true,  as  many  contend,  that  the  water  which  escapes  through 
the  bottom;  and  sides  of  porous  channels  finds  its  way  back  through 
natural  channels  and  is  again  diverted  and  used  for  beneficial 
purposes.  There  is,  I believe,  only  a relatively  small  part  which 
is  thus  utilized.  By  far  the  greater  part  is  not  only  lost  but  it  is 
worse  than  wasted  since  it  collects,  as  a rule,  at  the  lower  levels  of 
valuable  lands,  raises  the  water  table,  submerges  the  roots  of  crops, 
causes  alkali  to  rise  to  the  surface,  and  in  general  converts  valuable 
fields  and  orchards  into  pasture  lands  of  Bermuda  grass  and  salt 
grass.  The  value  of  water  is  on  the  increase  and  farmers  now 
are  not  infrequently  called  upon  to  pay  over  $40.00  per  acre  for  a 
water  right.  Instead  of  reaching  out  to  the  unappropriated  water 
supplies  o*  the  West  for  fresh  supplies  to  meet  the  ever  increasing 
demands,  it  will  prove  a better  investment  to  take  measures  to 
save  a part  of  what  is  now  appropriated. 
The  scarcity  and  high  cost  of  water  in  some  parts  of  the  West 
have  compelled  water  users  to  take  steps  to  prevent  losses  in  trans- 
mission. This  can  readily  be  done  by  canal  lining  since  evapora- 
tion losses  from  the  surface  of  a canal  are  small  in  proportion  to 
the  seepage  losses.  A number  of  different  materials  have  been 
used  for  this  purpose,  consisting  of  heavy  asphaltic  oil,  clay  puddle, 
wooden  flumes  and  cement  concrete.  In  view  of  the  high  price  of 
lumber  and  the  inefficiency  of  petroleum  oils,  engineers  are  rapidly 
coming  to  the  conclusion  that  concrete  is  the  best  material  for  such 
purposes.  Cement  and  concrete  linings  have  been  applied  to  canals 
in  thicknesses  varying  from  three-fourths  of  an  inch  to  six  inches 
and  more  in  thickness.  A thin  plastered  coating  can  be  applied  at 
small  cost.  The  cost  of  a lining  of  concrete  from  two  to  three 
inches  in  thickness  will  vary  from  5 to  7J/2  cents  per  square  foot. 
This  cost  is  not  prohibitive  and  it  will  usually  be  found  that  if  the 
water  which  it  saves  is  properly  used  it  will  prove  a good  invest 
ment. 
The  use  of  concrete  in  lining  canals  to  prevent  seepage  has  led 
to  its  use  in  other  irrigated  structures,  such  as  dams  and  drops, 
gates  and  division  boxes,  pipes  and  drains,  culverts  and  bridges. 
This  change  from  the  use  of  wood  to  cement  concrete  has  been 
brought  about  largely  by  the  increase  in  the  price  of  lumber  and 
the  corresponding  decrease  in  the  price  of  Portland  cement.  In 
building  irrigation  works  some  25  years  ago  in  Colorado,  the  im- 
ported Portland  cement  cost  over  $8.00  per  barrel,  while  the  price 
