|
PROCEDURE:
|
- Using the Water Resources
Data for the State of Florida
(United States Geological Survey), available on the Internet, select two
gauging sites in the Saint Johns River of Florida. Select sites where at
least 25 years of data exist. Record at least 25 consecutive yearly
maximum flow and stage values at each site along with information
concerning location of gauging stations including contributing area at
each gage.
- Using the flow data
collected and the DISTRIB for Windows program predict the 10, 25, 50,
and 100 year return period maximum flows for the two stations.
- Compute the percent of each
return period maximum flow relative to the 100 year return period
maximum flow.
- Calculate the unit flow at
each site and express your answer in units of cfs/square mile/year and
inches per year.
- Text Problems 2.7.1 (6,8)
& 2.7.2 (1)
|
|
OUTPUT:
|
The procedure followed in this lab has an ultimate outcome of predicting
the flow rate due to an extreme event (10, 25, 50, or 100 Year Return
Period). The distribution analysis is the portion which provides the
prediction of the flow rate for an assumed return period.
Your report should include the following:
- Locator map including
the general area of the gauging stations (Appendix).
- A tabulation of the
year, stage, and flow used in developing the distribution (Appendix).
- A tabulation (for each
station) of the return period, the predicted flow, and the percent
relative to the 100 year flow for that return period (Results).
- A discussion of the
size of your data set and how that relates to the uncertainty of your
results, i.e., estimate reliability using Table 2.5 of your textbook
(Discussion/Conclusion).
- Careful examination of
the yearly maximum stage and flow values may show similar flow values
with varied stages, or vice versa. Discuss why this occurs
(Discussion/Conclusion).
- Calculations for the
unit flow rates.
- The Text problems
assigned.
You will need to locate water resources data for your site. These data are
available on the web or in hard copy, as in the library under U.S.G.S. Water
Resources Data. The researching of these data is an exercise for the student
(hint: the U.S.G.S. main computer address is www.usgs.gov and the water resources data will be in
government documents in the library).
|
|
DISCUSSION
QUESTION:
|
Please generate historical hydrographs for the two
locations along the St Johns River that you
chose for this lab. Are there any major differences between the two
hydrographs (maybe the average flow rate changes, etc.)? Please explain why
this would occur.
After analyzing the historical hydrographs, you'll probably notice some
extreme peaks or extreme valleys. Please provide real-life reasons as to why
these events occurred (i.e., provide rainfall data, hurricane data, dam
issues, construction issues, etc.). Also provide a source for your data.
|