The record for the Arroyo Seco gage extends back to 1914 so it is exceptionally long record

so the flow forecasts you make should be pretty reliable. I would encourage to explore the web

sites referenced above.

Download the data per the directions at the end of the problem. This may be useful in future

work we do in this class or for your future career.

a) Develop the Log Pearson III analysis from the data download. Determine the 10, 25, 50,

100 and 200 year recurrence interval flows, cfs. (not log of the cfs values).

b) Develop a Gumbel Extreme Value analysis using the same data and for the same

recurrence intervals; you may use 3.92 as the Gumbel K for Tr= 200 years and 100 data

points (close enough). Don't do any interpolation. Use the actual flow values for Gumbel

analysis not the logarithms.

c) How do they compare?

d) To evaluate how the length of record could impact the results, just for comparison, do a

Log Pearson III analysis for the period 2000 to 2020. Compare with the entire record

from part a).

e) The bridge that is proposed will take 3 years to construct and we would like to know what

the design flow should be for our by-pass culverts around the bridge site. We are willing

to take an 85% risk that the by-pass culvert and channels would not be overtopped

during the three year period. Based on the results of the Log Pearson III analysis in part

a) what flow rate, cfs, would you recommend for the design?