CE 578/678 Water Quality Modeling

Department of Civil and Environmental Engineering

Portland State University

Spring 2005

First, download the model CE-QUAL-W2 from the web page

http://www.cee.pdx.edu/w2

This includes the model executables and example problems and the all-important User Manual. You will have to register on-line to get the model – but it is ‘free’.

From the class web page I have put the following files:

q A background report on the information used to set-up the model

q The model files that can be used with the executables from the W2 web page

Your assignment is as follows:

Explore the impact of using flashboards on the Willamette Falls (at Oregon City) on dissolved oxygen and temperature in the system for the time period between Julian day 162.5-273.5 2001. The flashboards are used by PGE to provide more head for power generation. Please write a summary engineering report using the model to evaluate this alternative. Would you recommend they stop using the flashboards or not? What other alternatives could you explore with the model to improve water quality? Would your recommendation hold if they change the way the flows are handled at the Corps dams is changed (leading to less summer flow)? Assignment is due on the date of the final examination.

Note:

Water quality and temperature standards for this section of the Willamette River:

Temperature (these are usually interpreted as 7-day mean maximums)

Above RM 50 64^oF

Below RM 50 68^oF

Dissolved Oxygen

Instantaneous DO>4 mg/l

‘Average’ DO above 6.5 mg/l until September 31; then above 8 mg/l after October 1.

Model Grid: