Geoscience Reference
In-Depth Information
312.5
312.0
311.5
311.0
310.5
310,0
309.5
309.0
0
50
100
150
200
250
300
Discharge [m
3
·s
-1
]
Fig. 2 Hydraulic characteristic of side channel spillway of the Złotniki reservoir for the existing
state (analytical solution)
Calculations of flood waves transformation (Machajski and Olearczyk
2009
)
showed that for the existing outlet installations there is no possibility to preserve a
safe dam crest height above the maximum water level in reservoir equal to 1.0 m
(Rozporz˛dzenie
2007
). So, for flood wave
Q
0.5%
passage, in an initial state of
reservoir fulfillment of 303.03 m asl, the water level in the reservoir reaches 312.35
m asl, that is, exceeds by 0.35 m the dam crest, and in an initial state of reservoir
fulfillment of 309.30 m asl, the water level in the reservoir reaches 312.50 m asl,
that is, exceeds by 0.50 m the dam crest. For the flood wave
Q
0
:
1
%
passage, a water
level in the reservoir will exceed by about 0.50 m the dam crest in an initial state of
water level equal to 303.03 m asl, and by about 0.80 m in an initial state of 309.30 m
asl, which means a dam crest overflow in each computational case. Results of
transformation calculations are shown in Figs.
3
and
4
.
The calculations reveal that a free flow of computational discharge through the
existing spillway is not possible, due to too shallow and too narrow flume in the
upper part (Fig.
5
), hence the flume should be deepened by about 2.50 m with
simultaneous set of its width at 15.0 m. Under such conditions, the assumed
discharge of spillway can be obtained for damming water level in the reservoir
for 312.00 m asl. These requirements offer a possibility of the rebuilding in
question, mainly in economic aspect. The reconstruction would force a necessity
of constructional changes of the weir - new static conditions of its work, and a
necessity of constructional changes of wall on the opposite side. However, the
essential advantages of rebuilding convince for such realization.
