Problem 4-1

The following snow-chart and hypsometric data have been measured in a certain catchment:

Elevation (%)	0	10	20	30	40	50	60	70	80	90	100
Cumulative Area (%)	0	24	40	52	66	77	82	86	95	98	100
Snow-water equivalent (mm)	3	3	3	4	4	5	5	7	7	8	8

Determine the catchment's overall snow-water equivalent.

Problem 4-2

Given the following stream gaging data, calculate the discharge.

Vertical no.	1	2	3	4	5	6	7	8	9	10	11
Distance to reference point (m)	5	10	15	20	25	30	35	40	45	50	55
Sounding depth (m)	0.0	0.6	0.9	1.3	1.5	2.6	3.1	2.3	1.3	0.8	0.0
Velocity at 0.2 depth (m/s)	0.0	0.5	0.7	0.9	1.2	1.4	1.7	1.3	0.9	0.7	0.0
Velocity at 0.8 depth (m/s)	0.0	0.3	0.5	0.7	0.9	1.1	1.4	1.1	0.7	0.5	0.0

Problem 4-3

A certain substance is introduced at point A of a stream at the rate of 100 L/s with a concentration of 10,000 ppm. At a downstream point B, after complete mixing, the concentration of the substance is measured to 16 ppm. Calculate the stream discharge.

Problem 4-4

Calculate the flood discharge of Clearwater River by the online slope-area method, given the following data: upstream flow area A_u = 4222 m², upstream wetted perimeter P_u = 770 m, upstream α_u = 1.17, downstream flow area A_d = 3353 m², downstream wetted perimeter P_d = 714 m, downstream α_d = 1.21, fall F = 0.45 m, reach length L = 1,598 m, and reach Manning's n = 0.03.