Mar. 13,1916 
A New Irrigation Weir 
1143 
no difficult form work required for the concrete, and it would make an 
inexpensive, durable, and satisfactory measuring device, especially if 
the angle-iron sides and crest of notch were used in connection with the 
concrete box. 
ADVANTAGES OF THE NEW IRRIGATION WEIR 
(1) The new irrigation weir is self-cleaning. The increasing velocity 
of the water from the time it enters the weir box until it passes through 
the weir notch prevents the deposit of sand and silt. Floating materials 
are also carried through the weir. 
(2) No lowering of the canal grade or building up of the banks is 
required for the construction of the weir box. The weir box has only 
one-fourth the depth and a less width than is required for a full-con¬ 
traction weir. Less excavation and less materials are needed in the 
construction, and the cost of the weir is therefore greatly decreased. 
(3) It may be installed by the farmer without expert assistance and 
with the tools* ordinarily at hand. Its operation does not require special 
training. 
(4) Its accuracy is consistent with practical demands and will remain 
constant. 
(5) It can not be easily tampered with or accidentally injured so as 
to alter its discharge. 
(6) There are no working parts which require attention for proper 
operation. There is practically no upkeep expense if the weir is well 
constructed of durable materials. 
(7) When the discharge tables are used, no computations are required, 
because the effect of velocity of approach is incorporated in the tables. 
The weir discharge is expressed in cubic feet per second, which may be 
converted into any units desired. An automatic recording gauge used 
in connection with this weir will give a record of the quantity of water 
discharged at all times, and the aggregate discharge can be computed 
from the record if desired. 
(8) It is not patented, and the entire cost of the weir is for materials 
and the labor of construction. 
