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suggest conditions similar to those of March, 1913, when the rain
fell continuously for 4 days, the ground and all vegetation was satu-
rated, and a time was reached during the storm when the water was
flowing off the water-shed at the same rate as it was falling from
the clouds; and if, in 1805, the snow and ice were added to the
precipitation, probably the run-off was greater than the rainfall.

The lack of rainfall records and data as to snow and ice conditions
makes it impossible to analyze the 1805 flood; but, if the virgin forests
did at that time retard the run-off and restrain the stream flow, then
the rainfall was probably greater than any on record on this water-shed,
and it is reasonable to suppose that it will be repeated in the future.
No bridges spanned the Miami in 1805, nor were there any other
artificial obstructions in the channel. River crossings were made at
fords, by boats, or by swimming, according to the necessities and con-
venience of the pioneers.

The forests doubtless have some retarding effect on run-off, up
to the point of saturation of the trees, undergrowth, and shrubbery.



1340 DISCUSSION ON FLOODS AND FLOOD PREVENTION

Mr. and of the litter and humus on the forest floor. After this point

■ has been reached, the soil in the forest is like that in the clearings,

and, as all great floods follow long-continued or very heavy downpours,

it would seem that, during the storm, the time must arrive when

the retarding effect of the forest is nil.

In Ohio, Indiana, and Illinois there is very little "standing tim-
ber", the water-sheds of the streams are denuded, and, after saturation
of the ground, the rainfall and run-off should be nearly, if not quite,
equal. The retarding influence of ponds and pools on uneven ground,
formed during storms, should not be neglected, but their effect on run-
off and stream flow, after all, will be small.

The proposition of reforestation with a view to flood control ia the
large navigable streams may be practicable for the bare lands of the
West, large areas of which are not under cultivation but are used only
for grazing purposes; but it will be impracticable for the valuable
agricultural lands in the valleys of rivers in the Central States. It is
scarcely conceivable that a farmer will give up his land to reforesta-
tion for flood control, waiting 40 to 50 years until the growing timber
on it becomes valuable, and meanwhile deriving very little or no re-
turn from the land; nor is it likely that any conservancy district could
afford to purchase such lands and reforest them for this purpose. In
any event, it is obvious that it would be many years before such re-
foresting could have much influence on the rate of run-off to the
streams.

The writer agrees with Mr. Grunsky that cut-offs are sometimes
advantageous, perhaps not in soil like that of the Mississippi channel
below Cairo; but, when made in glacial drift formation, experience
has shown that they will wear and accomplish good results in flood
discharge. Assuming the natural materials of the river channel to be
suitable for the maintenance of permanent cut-offs, there can be no
doubt that, in a certain instance, where a river, along its meanders
from its mouth to its head-waters, is now 170 miles long, and can be
shortened by cut-offs to 130 miles, that, with the new slope and in-
creased velocity, the flood-plain will be materially lowered everywhere
in its length.

Where the bends of a river embrace a populous city, a cut-off would
be prohibitive by reason of cost, and perhaps for other reasons, but
through farm lands and outside built-up city limits, it can be adopted
with advantage. Where the dredged material can be used in levees,
the cost of cut-offs will not be prohibitive. Some cut-offs may require
training walls, or spur dams, in order to maintain the alignment of the
channel, and the materials for these can often be found on the ground.

With the materials before it from which to draw, it is to be re-
gretted that the method of "flood prevention" by so-called "detention"
or "dry" reservoirs has not been more fully developed. The literature



DISCUSSION ON FLOODS AND FLOOD PREVENTION 1241

available to the writer shows few of such reservoirs, and none quite Mr.
recent in date of construction, if the work now under way on the
water-shed of the Little River in the southeastern part of Missouri,
and a few reservoirs in prospect,* may be excepted.

Suppose a water-shed, having 75% of its area embraced in the
drainage area of the small tributaries, generally of steeper slope than
the rivers they feed, with channels often narrow and comparatively
deep, often with rocky beds and conditions generally favoring the easy
construction of check dams or barriers, and where the valley next to
the river, as a rule, is wide and flat, and thoroughly developed, with
many populous and prosperous cities and towns along the stream, the
river very crooked, with the channel running through a drift forma-
tion ranging from builders' sand to large boulders, where cut-offs can
frequently be made to straighten and shorten the channel, the stability
of cut-offs and diversion channels in this instance having been proved
by a test of more than 60 years: Is not this an instance where the
retardation of flow — or, if desired, storage of water for flood protec-
tion — should be in the narrow valleys and ravines of the smaller tribu-
taries, rather than in the main valley; and is not this also an instance
where channel improvement will apply?

M. O. LEiGHTON,t M. Am. Soc. C. E. (by letter). — The writer's Mr.
impression, gained by reading this report, may be expressed substan- '^'^
tially as follows : Here is a Committee of eminently qualified engineers
— unquestionably as well qualified as could be selected from the Engi-
neering Profession. To this Committee has been assigned one of
the most important and difficult subjects in the engineering field. As
the members of the Committee are eminent engineers, it follows
naturally that they are very busy men. They realize, more acutely
than any reader of their report can, that they have not had the
time to give their subject the attention that it deserves. Having
accepted appointment to this Committee, they do not wish to shirk
the service involved. Therefore, they have made a safe and conserva-
tive report which, in all probability, each member regards as inadequate.

Perhaps the writer's impressions are wrong, but, having had the
benefit of acquaintance with some of the members of the Committee,
and having, during past years, become familiar with the reputation
and accomplishments of the others, he cannot avoid the conviction
that this report on floods and flood prevention falls considerably short
of the standards to which the Committee members have previously
adhered. Such a result is not unprecedented in the lives of busy and
well-qualified men.

The subject of floods and flood prevention is each year occupying
more of the time and attention of National legislators. Among these

* Briefly mentioned in Appendix 5, of the "Report of the Pittsburgh Flood
Commission".

t Washington, D. C.



1343 DISCUSSION OM FLOODS AND FLOOD PREVENTION

Mr. legislators, doubt and diversity of opinion seem to be growing apace.
eig ton. Q^^ ^^^ j^^g followed the events in Congress for the past ten years,
and who has therefore acquired a mental picture of the legislative
situation, must realize that the subject has not progressed to that
point of finality with respect to fundamental facts and remedial
measures which will insure a comprehensive legislative solution. The
flood question crops out in debate on measures both relevant and irrele-
vant. The same old truths and the same old fallacies are printed
each year in the Congressional Record. "With admirable persistence.
Senator Newlands of Nevada presents a great and comprehensive
proposal that involves every feature of correction and improvement
either closely or remotely related to stream flow and stream utilization.
With equal admirable persistence, other Members of Congress advo-
cate divers measures. The House of Eepresentatives has recently
created a new standing committee on floods and flood prevention,
and it remains to be seen what the practical results of this new move
will be. In connection with all this, two truths stand out prominently :
First, that the Members of Congress who are expected to legislate
wisely in this matter, and who, almost without exception, have no
engineering qualifications, have the right to expect from the foremost
civil engineering society of the country a definite and meritorious ex-
pression of opinion that will, in the end, define that which should be
done. Second, it is the patriotic duty of every engineer, and certainly
of this great National Society of Civil Engineers, to satisfy the reason-
able expectations of the legislators.

It does not benefit any legislator to tell him about fundamental
principles or to give him a summary of the things which cannot or
which should not be done. The legislator is looking for a concrete
proposal that will stand the test of analysis. A legislator who may be
utterly incapable of formulating a proposal may be quite successful
in analyzing, criticising, and pointing out, the weak spots in a proposal
submitted to him by qualified engineers. Let us not deceive ourselves
about this matter. If the flood problem is to receive final and success-
ful legislative treatment, it will be only after the engineers of the
country have come forward with a definite legislative measure, based
on physical facts and well-attested engineering principles. This state-
ment may do violence to the sacred tenets of the American Society of
Civil Engineers. The writer can already hear the deprecatory expres-
sions of many members with respect to the Society's participation in
legislative matters and advocacy of any particular proposal. There is
no doubt that such an attitude is comfortable, dignified, and utterly
safe, but the fact remains that, if the Society expects to see the con-
summation of a successful solution of this problem, it must do the
useful and necessary thing, rather than the dignified and com-
fortable one.



DISCUSSION ON" FLOODS AND FLOOD PREVENTION 1243

There is no trade or profession in the United States in which one Mr



may find such persistent and general expressions of discontent over
the inadequacy of legislation as in the Engineering Profession. It is
also fair to say that, in the opinion of the writer, there is no profession
in which such expressions are so intelligently and considerately given.
On the other hand, it is the writer's observation that there is no class
of complaining citizens which so consistently fails to come to the aid
of legislators with definite concrete advice. If the members of the
Society dissent from this statement, let them ask the legislators.

From the foregoing, it will be seen that the writer criticises the
Flood Committee's report because it leaves the country and the
country's legislators precisely where they were before the Committee
undertook its labors. If a traveler who has lost his bearings and has
become confused amid a maze of divergent paths, asks the route to
his destination, he is not benefited by a reply which says in effect:
"Friend, you must take the proper road that leads to your destination ;
if you go by the wrong road, you will probably not arrive." The
writer is very glad that the Committee has been continued, and he
submits the foregoing humble suggestions in the hope that they may
have some bearing with respect to the future report which it is assumed
that the Committee will make.

With respect to the actual findings of the report, the writer agrees
in the main with the minority views of Mr. Knowles. Though it is
true that many of the sentences which Mr. Knowles proposes in substi-
tution are, in the opinion of the writer, merely improvements in
English composition, they do add to the judicial temperament of the
report.

The Committee's conclusions (page 1228) with respect to reforesta-
tion may or may not be correct. The writer believes that they are in-
correct, but, assuming their entire correctness, it is apparent, to the
unbiased readers to whom the writer has submitted this paragraph, that
the Committee has either consciously or unconsciously made a seem-
ingly judicial statement which, among legal brethren, would be re-
garded as a very adroit special plea. The half-truth expressed in this
short paragraph does more to convince the reader against reforestation
than would the plain blunt statement that forest growth has no effect
whatsoever. Paraphrasing the concluding words of the statement, the
Committee, with equal truth, could have said: "But there has been
no quantitative determination of its influence on stream flow which
would justify its exclusion as a method of flood prevention." The
writer is familiar with intensive investigations, the results of which
have unfortimately never been published, which show mathematically
that forest growth does, under certain conditions like those prevailing



Leighton.



1244 DISCUSSION ox floods and flood prevention

Mr. in the White Mountain region of j^ew Hampshire, markedly reduce
e'sr on. ^^ meliorate flood extremes.

The Committee has disposed of reservoirs and detention basins as
factors in flood prevention by a few short, obvious, and rarely dis-
puted statements. They give the reader the impression that the Com-
mittee, on the whole, is doubtful concerning reservoir efficiency; yet,
after one thoroughly analyzes the section, he may be able to agree with
every statement and still remain a pronounced advocate of reservoirs.
This advocacy does not commit any one to the reservoir theory under
all circumstances and conditions. It merely cojnmits the believer in
reservoirs to the old common law doctrine that every cause is entitled
to its day in court. An apparently reluctant admission, such as that
made by the Committee, that reservoirs may be beneficial under some
conditions, cannot act as a counter-weight to a series of objections and
adverse implications which may or may not apply in any particular
case. There is, to say the least, a lack of fairness in a pronovmce-
ment which gives qualified approval to reservoirs and then cites a
series of adverse conditions without also giving to them equal and well-
merited qualifications. Altogether, Mr. Knowles' expression "damning
with faint praise" is applicable and well-chosen.

The Committee has wisely set forth the deficient and unsatisfac-
tory condition of available stream flow data. It might, with equal
wisdom, have set forth the unsatisfactory condition of our knowledge
with respect to detailed topography, reservoir sites, and storage man-
agement. These deficiencies have been apparent for a score of years.
What has the American Society of Civil Engineers done to correct
that condition? Federal and State appropriations for such investi-
gations have either been lacking or inadequate, but that is a natural
consequence of the lack of information on the part of the people. It
cannot fairly be expected that any considerable body of voting citizens
is going to become enthusiastic o.ver a fundamental engineering neces-
sity which they do not understand. Who is there to explain and
instruct, except the engineers of the country? The lack of appropria-
tions is not entirely responsible for the paucity of data. Some of
the blame can be traced to the inefficient expenditure of the money
that has been provided. In making this statement, the writer does
not intend to reflect on any particular State or Government Bureau,
and, if he were disposed to make comparisons, there is one particular
Government Bureau which he would exclude from this category, be-
cause it has come pretty close to making each dollar produce results
to the value of two dollars. The fact remains, however, that engineers,
and especially those in official life, have not expended their efforts
and appropriations along the most purposeful lines. Looking back
over the history of river hydraulics in America, we commonly start
with the work of Humphreys and Abbot on the Lower Mississippi.



DISCUSSION ON FLOODS AXD FLOOD PREVENTION' 1245

That classic investigation had one bad result. The engineers accepted Mr.
it as a finality rather than a most remarkable beginning. Perusal of *^'^ ^'
the reports of investigations that took place during the 25 or 30 years
subsequent to the Mississippi investigation will show that the efforts
were largely devoted to an attempt to prove how eternally right or
how grievously wrong were Humphreys and Abbot. Had our work
on river hydraulics during those years been a forward movement,
rather than a post mortem, our present Committee on Floods and Flood
Prevention would undoubtedly have found itself less embarrassed
by a lack of fundamental data. A recital of past eri'ors is useful
only in so far as it may serve as a guide to future conduct. This
Flood Committee could, if it desired, do more than merely report regret-
fully the deficiencies in our fundamental facts. It could, if it chose,
become the fountain head of a campaign by which a beneficial change
of conditions could be brought about.

Cyrus C. Babb,* M. Am. Soc. C. E. (by letter). — This report is a Mr.
good, concise statement of our present knowledge regarding floods * '
and flood prevention methods. It brings out forcibly the lack of
adequate engineering data on this extremely important subject.

It may be that the data collected by the Special Committee are
too voluminous for detailed tabulation in a comprehensive report, but
it would seem as though a bibliography or reference table of such
data, arranged by drainage areas where possible, might be published
with profit to the Society.

It seems to the writer that the Minority Report by Mr. Knowles
contains, in a few cases, better expressions for the same ideas than
those submitted by the majority. The second heading is a more fair
presentation, giving the advocates of reforestation an even standing
with the opponents.

The writer is in hearty accord witjb Mr. Knowles' twelfth heading
and of placing it at the end of the report. It would seem as though
the U. S. Geological Survey, through its Water Resources Division,
was the proper bureau to carry on the investigation. This Division
might well be elevated to the rank of an independent bureau, as was
done a few years ago in the case of the U. S. Reclamation Service.

Kenneth C. Grant,! M. Am. Soc. C. E. (by letter). — Experience Mr.
in connection with flood prevention legislation and investigations has ^^^^ '
strongly impressed on the writer the value of a carefully prepared
report on the general subject of floods and flood prevention, such as
has recently been submitted by the Special Committee. Such a report,
to measure up to its greatest possible usefulness, should deal with
every possible phase of the subject, and should set forth clearly the

* Rhodhis.



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