Decorah public opinion. (Decorah, Winneshiek County [Iowa]) 1895-1928, 1908-09-16
IMPORTANCE OF DRAINAGE.
Kidding Roads Of Storm and Underground
Water Subject Of Thoughtful Paper.
By the Office Of Public Roads.


By the Office OF Public Roads.
With an average of $1,000 tons of
water falling in the form of rain on
each mile of public road in the
United States annually, it is scarcely
to be marvelled at that the ten COM
mandments of the road builder can be
summed up succinctly in the word
drainage.
The saying has truth for a basis. as
good drainage is the primary requisite
for all roads. Even in sand roads this
holds true, for there ''good drain
age" means such as will safely remove
the storm water without rosion or
Outlying and still retain the surface
moisture.
To secure good drainage one must
take into consideration both the sur.
face water and the underground
water. The surface water must be re-
moved quickly and completely and
without subjecting the road to exces-
sive scour or erosion. For this rea.
son, the center of the road should be
raised and the slope toward the side
bitches should be from one-half to
one inch to each foot distance, or so
that the water will run freely to the
side bitches and not flow down the
road or remain in puddles on the
roadway. The side bitches should be
of ample size to care for the severest
storms with fall of not less than six
inches to each 100 feet Frequent
and ample cross drains should be con-
structed and every opportunity taken
to get the water away from the road
as quickly as possible. Any road
along which you see water standing
In the side bitches or on which pud-
dies of water have collected or which
has been badly gull and eroded by
the rains has poor drainage and is in
need of immediate attention In fact
earth roads nearly always require
little attention after each rain. The
split-log drag is essentially tool to
maintain good drainage on our earth
roads. and should he used after each
rain. On heavy clay or gumbo soil
the drag when properly used tends to
puddle the road surface. keep it free
from ruts. dense. smooth and hard,
thus securing the best surface drain
age possible.
But in many places the underground
water is too near the surface and
must be removed before good road
will be possible. This means that
some form Of sub-drainage must be
resorted to. usually tile drains, of clay
or concrete. Water from whatever
source must be gotten rid of effective
ly. for water plus clay or gumbo in
variably equals mud when mixed in
spring and summer. Water becomes
ice in winter and rs water in freezing
expands one-eighth its volume. the
ROAD heaves out of shape and when
the ice mel the road disappears be-
meath the rising tide OF mud constant
ly fed by rains. melting SHOWS and
underground springs.
In seepy and DOGGY places the SUBJ
drainage in order to be fully effective
should lower the water level to not
less than three feet below the road sur
face. If tiles are used they should be
carefully laid, true to grade. Most
failures in tile drainage can be at
tributed to carelessness in laying. or
too fat grade. Tile less than four
inches in diameter should rarely be
used, nor should grade of less than
6 inches to the 100 feet be used unless
absolutely necessary. In very dense
soil. it is always advisable to cover
the tile to at least depth of 6 to IL
inches with coarse sand or fine gravel
Care should always be taken to secure
a free outlet for the drains and to
protect the outlet with a concrete
bulkhead or catchbasin, which can al.
ways be kept clean and the outlet
free
The kind of tile to be used depends
on local conditions. Concrete tile if
properly made are equally as good as
clay tile. Which kind to use is en-
tirely local question of dollars and
cents. If concrete tile can be made
more cheaply than clay tile can be
had, use concrete: if not. use clay
tile.
One great advantage of the concrete
tile is that they can be easily made
by the local users at or near the place
where they are to be placed. so that
che freight charges are dispensed with
as we'll as the large breakage losses
due to handling. Placed in the
ground, both are durable. If concrete
is used. great care should be taken to
see that good grade of Portland &C.