Oldman river has Goldeye/Mooneye, Walleye, Sauger, pike, sturgeon, suckers, rainbows, browns in various numbers right in the city. Access at or near bridges. Not sure what the banks are like - use caution.
Nicklas Sheran(sp) lake Westside has brookies, perch and pike.
Reservoirs around Lethbridge contain pike walleye and whitefish.
Have fun