Stream discharge varies greatly over time, largely in response

to variations in rainfall over the drainage basin and snowmelt

on the ground in the area that supplies water to the drainage

basin of a stream. A graph showing the variation in stream

discharge over time is referred to as a hydrograph. Using the

hydrograph for the Fraser River at Hope, B$.$C$.($Figure $2)$

answer the following questions.

Figure $2$ Annual hydrograph for Fraser River at Hope, B$.$C$.$

including annual precipitation.

a$)$ What months show average values of stream discharge greater

than $5500m^3{s}^{-1}?$

$(3$ marks$)$

b$)$ What months show average rainfall$/$snowfall values greater

than $200mm?$

$(3$ marks$)$

c$)$ Because greater amounts of rainfall in a drainage basin

usually lead to greater stream discharge values, we would

expect the peak discharge of the Fraser River to occur during

the winter months when precipitation values are highest. Why

does the opposite occur?

$(3$ marks$)$

State and explain two reasons why discharge monitoring is so

important.

$(3$ marks$)$