Honolulu star-bulletin. [volume] (Honolulu [Oahu, Hawaii]) 1912-2010, 1917-03-30
REPORTLOWERS
ESTIMATE Upon
FLOW OF. WATER
Eight Months Investigations of
HilleDrand Glen Puts Run
off at 20 Per Cent

OH al ~ Per Gent
GoveTner Pmkham's advice to the
Oaaii loan find commission to await
further data on run-off and rainfall
conditions In Hillehrand glen rather
than 40 ahead with construction g-ork
Tn the Maole water project was jnsti-
tied, judging from a report submitted
To the territorial water commission
by Roger c. Rice, photographic en-
ginees4
W lils The estimate made by James
r. 1aylgr, the engineer hired by the
loan fund commission to survey the
district and report on the feasibility
Of trying to conserve its rain waters,
Flaced etiie water runoff there at so
per cent OF the rainfall, Rice's figures
show the average less than half that
amount--20 per cent, TO be- exact.
Furthermore Rice's figures are TAX
en- on a longer period than those sent
in by Taylor, and are compiled by
actual measurements at the water
gage in Hjllebrand glen. They go
into detail as TO rainfall and water
run-off.
Governor insistent on Waiting
IL will be remembered that the
governor repeatedly advised the loan
commission against haste in the mat
ter, and that numerous discussions
arose on the subject, the commission
finally voting to call Tor bids. The
construction work is now in full
swing.
Prom results thus far said SUI
perintendent OF Hydrography George
X. l.arrlson, when asked regarding
Isngineer Rice report, the governor
wGs sstified in requesting moe de-
iay until information through actual
measurement had been secured"
Water engineers say that, judging
fsch the report and general conditions
in tiii.ebrand glen the average run-off
WI never exceed % per cent. Rice
advises still more study Of the situa
ton before reaching conclusions.
Accurate information Scarce
Very little accurate Information is
available OF the relation between rain.
fall and run-off for the narrow, pre-
ciritous, small valleys in the Hawaiian
Islands" he says in the report, and
especially those in the vicinity OF Ho-
noluln that are beng utilized more
and more as sources Of municipal wa
ter supply.
Rainfall records collected by the
1. S. Weather Bureau and the u. S.
Geological Survey, in the Hawaiian
Islands, are Invaluable for general
rainfall Information, but have seldom
been cDordinated with run-off records.
% establish factors suitable for spe.
clio localities.
The local practise of trying to
adapt fnn-off factors derived from
nfaiala1d localities that differ greatly
- climate. geologic ard topographic
features TO fit island problems is at
best Vtfy unsatisfactory. Local in
rostlEations between rainfall and run
off should be of great value in max
inc future flood storage estimates"
The report says that Maole stream
Is formed from several small inter.
mittent tributaries that cascade down
the steep sides Of the valley during
periods Of heavy rainfall. During or.
binary dry weather the stream is
very small, usually from $4,000 to.
10000 gallons day. The Hillebrand
glen project is TO utilize the storm
waters Of Maole stream for storage In
reservoir No. 4 BY the construction OF
diverting dam. tunnel and lined open
ditch. The Increased storage viii pro-
vide additional water supply for Nuu.|
anu valley and increase the power
available al the municipal electric
light plant at reservoir No. I.
Six Months investigation
From JuEe / 20 December 81, 1916,
the run-off factors for Hillebrand
glen varied frora practically nothing
to s5 per cent. says the report, ac-
cording 10 the intensity OF the storm
and the preriocs degree of saturation
Of the soil. A mean average runoff
Is &c per cent
The report states further that the
period OF investigation has been very
short and that the work should be
continued for a longer period so the
ISln off values for periods of heavy
precipitation may be obtained.
Eight Months Period
Actual run-off salues secured by the
measuring weir in Hillebrand glen
Cor the eight months are as follows:
Gallons
t,,-~ 100 mn