The record-union., 1891-02-20

recommended that Jacobs Slough, on
the east bank of the river, above Sacra-
mento, be closed to the hight of the nat
ural bank, the estimate for which is S25,-
600.
CONDITION OF THE RIVER JUST BELOW
CoLUSA.
From the mouth to Colusa, 166 miles,
the slope of the river bed is moderate,
and in this interval there are no rapids
worthy of note, so that navigation may
be considered as easy. But near Colusa
we find in ascending the river marked
steepening of slope, and consequent
rapidity OF current, shown in ripples or
rapids, which become more and more
frequent, flowing over gravelly bars in
channels of diminished depths. Over these
ripples it is no longer possible to carry in
low water, bargeS drawing four feet Of
water. Practically drafts at low stage are
reduced to three feet, and as we ascend
still higher further reduction takes
place, until near the head of navigation
no drafts greater than "a to 30 inches are
now maintained during low stages. In
this part of the river the alignment of the
channels which below is stable between
firm banks seldom disturbed to any ex-
tent by freshets or currents, becomes un-
certain, varying after floods by reason of
cut-offs or erosion OF banks, which here
are not able to resist violent current
action.
USELESS AT PRESENT TO ATTEMPT COR
RECTIoN NEAR CoLUSA.
The absence of firm banks, producing
a variable alignment, makes it impracti
cable in this part of the river to bring
about permanent increase Of channel
depths at particular points at moderate or
| justiiable cost. Permanent improve
| ment can be secured only by maintaining
| stable banks and fixed alignment. More
| over, caving banks supporting heavy
| growth of oaks and sycamores, supply
each year dangerous Instructions in the
| form of snags, which are also derived
| from the wooded regions near the head
waters of the river, whence they float
| down in freshetS.
Variable alignment, shoals, rapids and
snags are therefore the obstacles which
navigation in these upper waters encoun-
| terS each season. These serious obstacles
are expected upon the subsidence of
water in the spring and early summer,
and generally, it is not practicable to be-
| gin to move the wheat harvest until some
clearance of snags is made.
SNAGGING ADVISED.
! Permanent channel Improvement be-
| ing, by reason of cost, impracticable or
inexpedient, it has for some years been
the adopted policy to maintain on this
! part of the river a well-equipped Snag-
boat, which has removed or destroyed
channel snags, and where necessary has
| concentrated water by temporary wing
| dams and in other ways has permitted
navigation, which would otherwise have
| been impracticable. The board recon-
mends the continuance of this system,
and in view of the constantly recurring
need for work of this kind, it appears to
be expedient that the appropriation for
support of the system be made perma-
nent for each year. The sum of 900
WILL in the opinion of the board, gen
orally maintain drafts of four feet from
Sacramento to Colusa, and three feet or a
little less from Colusa to the head of nav
igation. ~
PROTECTING THE BANK.
These drifts are satisfactory to the
steamboat interests, and, in the opinion
of the board, they are sufficient for the
present needs of navigation and of the
adjoining country. Moreover, these
depths are as great as, in the opinion of
the board, can be secured by channel i'm
provements at justitiable cost. The board
suggests in addition to duties already
specified, the crew of the snagboat ought
to protect, as far as practicable, banks
undergoing erosion, with the double
view of preserving existing alignment
and of reducing the supply of snags due
to bank erosion.
CONTROL OF FLOOD WATERS.
1t has already been suggested that fur
| ther improvement may be obtained by
system of control of flood waters, which
| shall cause them to be discharged in
whole or in greater part between banks.
The present capacity of the river sections
is entirely inadequate to perform this
| duty. In no portion, when navigation is
convenient, does the river now carry all
the drainage water presented to it; in
some portions observations of floods in
dicate that the river does not carry more
| than halt, if so much.
Observations have not, however, indi-
Gated the maximum of drainage that need
to be provided for at particular points.
Sufficient data for the solution of the
problem do not yet exist, and they can
be obtained only by adequate observa-
ton. While it is now apparent that the
| problem is one of great magnitude, no
estimate of extent of works, or cost, or
interval of time necessary for the devel-
opment of an adequate system of drain
age can be stated at this date with any
approach in accuracy. The subject has
occupied the attention Of the engineering
staff of the State of California at intervals
for some years past. The United States
has taken no step in investigation of the
problem. The direct concern of the
United States in this matter relates to the
navigation interests. The State and peo-
pie of California are concerned not only
in the matter of navigation, but also, and
ton and reclamation of lands.
HOW DRAINAGE CAN BE EFFECTED.
Drainage can be effected only by sys-
tenn of levees. The United States is con-
cerned that the levee system shall be
properly aligned, and be adequate to the
duty required of it, namely: to compel
the flood waters to follow the course o1
the river channel, and thereby scour al
improved way. lnasmuch as successful
| frpafrnpnt rqn11irpS q 1arOa inproaSp n
channel capacity over length of 20(
miles or more, which must in the nature
of things be a gradual process, a number
of years viii be occupied in the complete
development of the system.
THE PATCHWORK SYSTEM CONDEMNED
A beginning in the way of reclaim.
alton and protection of land has
on the banks of the Sacramento
and Feather Rivers about $1,000, ,OO(
have been expended in isolated and un-
combined efforts of separate districts
each aiming to give local protection with
out concern tor the general interest.
In these operations the State has moi
undertaken to exercise engineering con-
j, troll. 1t has authorized certain localities
} or districts to raise funds for their OWL
respective protection, but has not indi.
Gated limitations or compelled co-opera.
! ton. 1t has resulted that certain districts
have provided good local protection
others have been less careful or less sue
cessful, and that the system, if it can be
, called system, has, SO far as constructed
exercised no beneficial influence of mag
nitude upon the general condition of tht
river channel. This. conclusion will be
come more evident when it is stated tha
in long stretches of the river but one banl
is leveed, while over the other wate
escapes freely into adjacent basins, from
which it is re-delivered to the river a.
time and topography permit.
FEATHER RIVER.