Evening star., 1921-01-29
Geological Survey
Asks Storage
for Water.
OVERFLOW COULD
RUN GENERATORS
Reserve of 3,4OO,O 900
Acre Feet Provided
In Report.

simultaneously with announce
ment by the federal power commits
sion of the findings and recon-
mendations of Maj. Tyler in his
report on the harnessing of Great
Falls for water power develop
ment. the United States geological
survey today made public a report
on the>water supply of the Potomac
river at Great Falls. The report,
compiled as a result of investiga-
tions made during 1920 by John c.
Hoyt and Guy c. Stevens, engineers
attached to the survey, will be con-
sidered jointly with the report of
Maj. Tyler.
The geological survey report sug-
gests that fourteen reservoir sites be
constructed along the Potomac river
from Petersburg. w. Va, to Great
Falls. thus providing a greater water
flow through the proposed develop
ment at the ultimate point of power de-
velopment at Great Falls. The fourteen
dams would store total of more
than 100000 acre feet of water (14S.-
million cubic feet) or more than 40
per cent Of the average annual rum of
from the basin from which the water
is drained. This means that by con-
struction Of these dams. 40 per cent
OF the average annual amount of
water lost by run-offs would be saved
for its ultimate use at Great Falls
Location for Dams.
The dams would be located as fol-
lows: At the South branch of the
Potomac river, at Petersburg, w. Va;
at the South branch of the Potomac
about 1900 feet above its mouth; at
Town creek, in Allegany county, Nd.
Va; at Swim Hollow, in Morgan coun-
ty, w. Va: at Hedgesville, Berkeley
county. WA; at Brooks Gap, Broad
way, Va: at Mount Crawford, Va; at
yerona, Va; at Port Republic, Va; at
Eikton: Va; At q site near Charles
doun county, Va. and the Potomac rivei
reservoir, 4bove Great Fails, where
the ultimate development Of power By
the use Of the water thus stored IL
proposed.
The report estimates that by the use
Of four reservoirs having total capac-
ity Of 81 600 million cubic feet a monthly
flow at Great Falls of not less than
5000, second feet, or 5000 cubic feet a
second, more than three times the
minimum flow considered available in
previous reports. without storage, could
have been maintained during the last
twenty-f1v years. -
This increase of about 1900 cubic feet
in the minimum flow If used in modern
hydroelectric plant operated with a head
Of 100 feet at IS per cent efficiency
would yield as much energy as 1856, 900
tons of coal per annum burned in an
efficient steam power plant consuming
hour of generated power. the report
says.
Average Flow. 11.0O0 Feet.
The report states that the Potomac
river at Great Falls has had an aver
age flow over twenty-three-year
period Of 1890 cubic fet second,
a maximum flow Of 248.000 cubic feet
and a minimum flow of 653 cubic feet,
and that the flow was less than 5000
cubic fet during 20 per cent Of the
time under consideration. During 1914
it averaged only 1.780 second feet
during 120. consecutive days. thereby
warranttng it's conclusion that a
steady flow Of 5000 cubic feet could
be maintained by the use Of four
reservoirs only.
The report indicates that storage
sites are sufficiently promising to
justify a thorough investigation of
their feasibility before final plans for
Falls are adopted.
The natural flow OF the Potomac.
the report says. comes from a basin
comprising 11.457 square miles, Of
which 10 per cent is below Point Of
Rocks, Md.
In making its computations. the re-
port says. engineers of the survey
have made no deductions for water
diverted past Great Falls at the
aqueduct dam for the water supply
OF the District of Columbia or for
the Chesapeake and Ohio canal. The
capacity Of the present water supply
conduit is about 135 second feet. and
estimated at about 10 second feet
The engineers concluded that If ad-
ditional water, is diverted at Great
Falls for the supply Of Washington
without construction Of storage dams
north Of the falls the water available
for power will be further reduced.
50 Per Cent Available.
Eighty per cent of the water flow
ing in the Potomac between Point of
Rocks and tidewater. distance OF
forty-four miles. involving a fall of
200 feet, would be available at Great
Falls under the proposal of the geo.
logical survey for dam construction.
OF the fall Of water. the survey states,
fifty feet occurs in the twenty-nin
miles between Point of Rocks and Great
Falls and $50 feet in the fifteen miles be-
tween Great Falls and tidewater. Engi-
neers conclude that because Of the rela-
lively small fall between Point OF Rocks
and Great Falls the facilities for wa
ter storage would be greatly in
creased and the engineering problems
made lighter.
The survey engineers do not make
any computations as to the probable
cost Of construction Of the fourteen
dams suggested, but urge that con-
structfon Of such dams would so in
crease the water available for power
at Great Falls that the two projects
might be considered as one and the
same.
May BE Studied Jointly.
It was considered probable today
that the two proposals would be con-
sidered Jointly at the public hearing
on Mai. Tyler's report to be held by
the Federal Power Commission Tues
day. The geological survey report
was made direct to Secretary Payne
Of the Interior Department, and by
him transmitted to the Federal Power
without recommendation.
The geological survey also made
public today a report on power pro-
duction in the United States by fuel
and water. The report shows that
1877. $50 thousands of kilowatt hours
were developed in the District Of CO.
Ism, bia by fuel during the first nine