Evening star. [volume] (Washington, D.C.) 1854-1972, 1893-01-07
ABOUT ROCK CREEK
Capt. Lusk Makes an Elaborate Re
port on It.
ITS VAL U E AS A SEWER
He Believes That the System OF Intercepting
Sewers Already Proposed is Better-Inter-
esting Calculations as to Rainfall and the
Volume of Observation-Disclosures of Cost Of I'm
provements.

On July %. 1892, the Senate passed the fol-
lowing resolution:
"That the Engineer Commissioner Of the
District of Columbia be, and he is hereby, in
structed to prepare plans, specifications and
estimates for converting Rock creek below the
north limo of Massachusetts, avenue into
closed sewer and filling in between the banks of
the creek; also to prepare an estimate of the
value to the government of the land reclaimed
by such work in excess Of the probable judy
ment of condemnation. Said report to be
made at the beginning of the next session Of
Congress.
Since the receipt of the resolution by the
Commissioners Capt. Rossell and his two as
sistants, Capts. Lusk and Fiebeger, have been
busily engaged in working up the necessary
data in reply thereto.
CAPT. LUsKs REPORT.
Today Capt. Luck made his report, which is
as follows
Capt. WM. 7. RossELL, Corps of Engineers,
u. 5. A.. Engineer Commissioner, d. c.:
SIR have the honor to report as follows
upon SO much of Senate resolution of July %,
1892. rs was committed to me. namely the
size, shape and estimated cost Of the sewer pro-
posed or conveying the waters of Rock creek
from Massachusetts, avenue extended to the
Potomac river.
THE ROCK CREEK BASIN.
Rock creek heads near Laytonville. Mont
gomery county, Nd, and from that point to its
mouth the general trend Of its basin is little
to the east of south. The distance in straight
line from the head Of the basin to the mouth of
the creek is between twenty and twenty lone
miles. The area Of the watershed is about
n. Is square miles. OF this CO. 81 square miles
is in Maryland, and the remainder, or lG. 80
square miles, lies within the District Of
Columbia. Practically the whole Of the former
area is row agricultural land. possibly one
eighth being wooded. Owing TO its prox-
unity to Washington, much OF this area may
be expected to gradually take suburban
and ultimately an urban character. OF the
area within the District 8,792 acres are either
paved and built upon, or to u greater or less
extent may be paved or built upon in the
future, while the remainder, or 1856 acres, is
included in parks or cemeteries and is likely to
remain so. From the head Of the stream to
| the general vicinity OF the Military road the
slope of the valley and the other conditions are
not at the present time favorable to very rapid
discharge, but the portion OF the watershed
from the road named southwark may properly
be considered as a very quick one. As a whole
the basin is free from ponds, lakes or marshes.
the presence OF which would tend to retard
the free discharge Of the rain fall
The highest known freshet il the Rock creek
'ehcy oSSuhhSo uuiiuS tuc uiSut VI May oil,
1889. So far as can learn no gauging of that
freshet WAS made. Several well-defired and
accurate high-water marks are known to me.
but they are SO far apart and the character of
the stream between them is such az to preclude
any trustworthy computation Of the discharge
of the stream at its highest stage. The highest
| recorded freshet discharge, taken at the mouth
OF the creek, is about 10000 cubic feet per Sec
ond. (See Appendix B.. From a considera-
ton Of the features Of the question which bear
upon the possible extreme discharge to be ex-
pected from the basin am led to place it at
about 20 900 cubic feet per second. do not
believe that SO great o discharge can be ex-
Pected from the watershed in its present con-
dition or In the future, unless exceptional cir
cumstances prevail, but owing 20 the vast an
terests involved remote contingencies must be
provided for.
TIE PROBLEM.
The proposition to arch over the lower part
OF Rock creek means that dam Of unusual
thickness, with its top at Tie elevation Of about
seventy feet, IL to be thrown across the valley Of
the creek from its mouth TO its intersection
with Massachusetts, avenue extended. thus con.
verting the valley above the dam to tho height
OF the contour Of seventy feet into . reservoir.