Montana oil and mining journal. [volume] (Great Falls, Mont.) 1931-1953, 1938-09-10
Road Types Reflect Worried
Needs State Has Considered
in Building Highway System

! wise require additional excavation.
] Funds always have some limit and are
rarely. If ever, available in sufficient
! quantity to fill human needs. 1t Is not
surprising then that the early highway
/ commissions adopted the policy Of sub
ordinating construction standards TO
mileage built and 1t Is through this
policy that Montana has been able to
construct and have available In such
q short period Of time, the existing
5000 miles of improved highway.
In the early improvement period al
most any mud-free surface looked good
to the public but by the early SOS
traffic had so increased as to make
travel disagreeable and hazardous on
account of the dust. 1t was imperative
that as much mileage as possible should
be dust PROCEED. and since treatment
with bituminous binders was the cheap
est and fastest method, work along
these lines has been carried forward
so that over 1000 miles Of the system
are now dustless.
Now it may seem paradox, but the
very conditions which make for g per-
feet gravel macadam road are those
which are ruinous to an oiled surface.
Ordinary soils have, In varying degrees,
the property Of pumping subsou mois-
ture to the surface, called in technical
language, capIllarity. On graveled sur
faces this property Is q distinct aid In
keeping down dust, especially where
ground water Is close to the surface.
When moisture Is brought TO the sur
face Of a graveled road it tends TO
cement the fine particles together and
any excess water passes away through
evaporation. But cut off evaporation
through the application Of q bitumin-
tied surface and the excess water is
trapped Immediately below the imper-
viouS coat. Excess water IN soil makes
mud, which has no great bearing
power, so 1t can readily be seen what
happens to our roads In spring and
why.
AS before noted, the expansion Of
dustless mileage as rapidly as possible
became necessary on account of In
creased traffic and the dust hazard
created thereby. It was perfectly feas-
ible to make these surfaces proof
against subsoiI moisture by the methods |
used today The difficulty lay in the |
cost involved and the time required. |
There was no time to be lost nor suf- |
ficient funds to make permanent sur
faces. Neither was 1t considered eco
nomically sound to expend large sums /
on those portions Of the system which I
were destined to become obsolete in a I
very short while anyway on account /
of their poor alignment and narrow
roadways. Thus 1t is that we have so
large a percentage of road mileage /
which must needs be reconditioned /
each spring with ever increasing cost !
of maintenance.
In 1884 the highway commission Of
the period judged that because Of the
near completion of main routes, the
time was ripe for a change in policy
and adopted much higher construction
standards which were au1lfcahle bntl1
to new improvements and reconstruc-
tons of existing facilities The vast
in comfort and safety can
be noted by any driver who may use
our roads.
The problem now confronting the
commission is to find the
rational balance between new extern
sions and reconstructions Of the exist
ing roads. A large mileage Of the earlier
construction is already ripe for re-
from the standpoint of pub
lie convenience and safety, complicated
by the more serious feature Of excessive
maintenance cost. At the same time
there is a strong public demand for
additional facilities. Funds are strictly
limited and in the end the problem
will revert to the public for an answer
TO the query, how much are you will
ing to pay for your roads?"
later article win discuss the state
wide highway planning survey which
was set up to gather and analyze all
the data bearing on the future high
way program, while another will dis
cuSs the present fiscal situation.
Feeder roads also will be discussed in
D separate article, since the problem
there Is considerably different and
much simpler than that encountered
On the primary system