This chapter employs Siletz River data for the continuous period 1925-1999. As of this writing, peak flow data through water year 2010 are available on the USGS Oregon surface water data webpage waterdata.usgs.gov/or/nwis/sw, including for Gage Number 14305500, which is the Siletz River. You will be asked in different problems in this chapter to update the Chapter 3 examples by using the 86-year record, 1925-2010.
a) Download the peak flow data for the Siletz River and enter the data into a spreadsheet.
b) Plot the 86 years of peak flows (1925-2010) and a 5-yr running mean vs. their water year, to update Fig. 3-2. Comment in general about the appearance of this time series, in the manner of the discussion of Fig. 3-2.
c) Using the updated data, develop new relative frequency and cumulative frequency histograms, that is, update Figs. 3-4 and 3-5.