Geoscience Reference
In-Depth Information
Table 3.
Return periods of critical years.
Discharge (m
3
/
s)
Year
Year of occurrence
F
(
q
)
Return period
Maximum inflow
1964
8971
0.9646
28.24
Maximum outflow
1964
3029
0.9831
59.17
Minimum inflow
1974
1000
0.1308
1.150
Minimum outflow
1954
416
0.0000
1.000
Average
1969
2872
0.1565
1.190
Graph of Annual Peak Inflows Vs. Return Period
T for for L. Albert
12,000
10,000
8,000
6,000
4,000
2,000
0
0
50
100
150
200
250
Return Period T, (years)
Fig. 2.
Graph of annual maximum inflow against return period.
Logarithmic Frequency Curve of Annual Peak
Inflows Vs. Return Period T for L.Albert
12,000
y = 1633.1Ln(x) + 1654.9
10,000
8,000
6,000
4,000
2,000
0
1
10
100
1,000
Return Period T (years)
Fig. 3.
Semi-logarithmic plot of inflows against return periods.
occur more frequently than maximum outflows and the maximum inflow
is nearly three times greater in magnitude to the maximum outflow. The
plots of annual maximum inflows against return period are shown in Figs. 2
and 3. The plots for the outflows are similar in shape but with lower values.
