48 
BULLETIN 906, U. S. DEPARTMENT OF AGRICULTURE. 
"ig. 30. — A distributing hydrant to reduce water pressure 
on hillsides. 
type is that gates 
must be regulated 
very accurately 
where a large num- 
ber of orchard hy- 
drants are fed simul- 
taneously. As a rule 
such construction is 
best adapted to 
grades that will al- 
low enough orchard 
hydrants between 
two successive 
stands to take all 
the water carried by 
the pipe line. 
A third plan that 
is also adaptable to 
comparatively small pressures is to provide standpipes at intervals 
high enough to back water from one to another (fig. 34). The stands 
may be made of concrete pipe cemented together and set up verti- 
cally. A slide gate is cemented to the discharge pipe at each stand, 
leaving the inlet open. When the gate is closed, water will rise in 
the stand until it is backed up to the one above it. If an excess of 
water is turned in the pipe line, these stands will overflow and thus 
relieve the pressure. This plan is advisable where the gate can 
be easily manipu- 
lated from the top 
of the stands. If 
the standpipe is too 
high, it is possible to 
install a gate valve 
or irrigation valve 
that is boxed in, 
leaving the handle 
of the gate to project 
through a packing 
box in the top . Some 
companies have in- 
stalled a short aux- 
iliary stand imme- 
diately below the 
main standpipe. 
This stand Contains fig. 31. — Another type of hydrant shown in Fig. 30. 
