Llyn y Gweision (a Welsh lake) has a surface area of 10 km2. It is fed by two rivers: the Afon Chwefru and the Nant Aeron. The Chwefru(Ich) has a catchment area of 1250 km2. The Aeron(Iae) has a catchment area of 2.400 * 106 ha. The outflow stream, the Afon Rhondda (Orh) has an average annual flow rate of 1367.6 ft3 s-1 (c.f.s). Rainfall in the region is 40.0 inches y-1, and annual evaporation from the lake surface is 8.10 * 106 m3.The equilibrium amount of water stored in the lake is 0.550 km3. Of the total amount of rainfall over the Chwefru basin, 32.0% leaves the basin as streamflow. For the Aeron basin, the annual streamflow amounts to an equivalent water depth of 33.87 mm over the whole basin. Show that for the above inputs and outputs that S = 0. If 10% of the flow from the Chwefru is diverted for municipal water supply, how much will lake level fall in one year; all else staying the same?

Question

A friendly (continuity) equation might be:

(I(Chwefru)+ I(Nant Aeron) + I(precipitation in lake) ) - (0(Rhonnda) + O(evaporation).
) = SL

where Ii = Inputs, Oi = Outputs and S = change in storage.

Answer 1

so far, i have concluded that
input for chwefru would be 1250 km2 and for iput for aeron it is 2.400*10^6 ha. but do i change the units? and i don't understand wat to do for percipitation

Answer 2

hey..i have this same question problem and i also posted this same question here in this site..and as far as i understand u need to get each in m^3/year...!!

Answer 3

m^3/ year as your final units?!

Answer 4

no..i meant that input shud all b in m^3/year...den output also..and the other individual parts as well..so change in storage will also b in m^3/year..and change in storage must b zero..!!

i was wondering...by any chance do u have a question number 1a.b.c.d.e??..if so..can u tell me wat value did u get for each (in u have dis rainfall related question den)..!

Answer 5

no need for 1a b c d e..i think my one is already right!!:)