This paper reviews the flood frequency characteristics of the Red River at
Winnipeg. The impacts of persistence in the flood series on estimates of fl
ood quantiles and their associated confidence intervals are examined. This
is done by generating a large number of data sequences using a mixed noise
model that preserves the short-term and long-term correlation structures of
the observed flood series. The results reveal that persistence in the data
series can lead to a slight increase in the expected flood magnitude for a
given return period. More importantly, persistence is shown to dramaticall
y increase the uncertainty associated with estimated flood quantiles. The 1
17-year flood series for the Red River at Winnipeg is demonstrated to be eq
uivalent to roughly 45 years of independent data.