We can use a staff gauge to get the information

in an indirect way to calculate the stream flow. If we place the staff gauge

near a section of stream for which you are collecting flow data, you can

identify the corelation between stream depth & stream flow. Once you got

this relationship so we can calculate flow from the stream depth without having

to take a time to make a detailed flow measurement. A staff gauge having

numerically labeled divided in lines to take the measurement of water &

calculate easily the depth & stream flow.

WHY WE

USE STAFF GAGE

The staff gage is a long ruler placed half-permanently

in a stream or lake used to measure the water depth. Staff gages are the most useful & common for measurement. place the

staff gages in a lake. Place the three staff gauges because in mid portion the

lake water velocity is different as compared to the side of lake. There is some

resistance at the side of lake that’s why we place the multiple staff gauge. If

a staff gages place on non-vertical place so knowing that the staff gauges

reading is correct or not.

USING A STAFF GAGE

0.43ft/secx10.73ft=4.62cfs.

Velocity (ft/sec) by the cross-sectional area (ft.) of the stream.

5. Now calculate the discharge in

cft/second & multiply the

0.5×0.85=0.43ft/sec.

4. Calculate

the mid-depth of stream velocity by multiply the surface velocity by 0.85.

50 feet/100sec=0.5sec.

3. Now

we will determine the velocity by which the distance covered by float divided

by the average amount of time it taken to cover the distance. If the distance is 50 feet and the time

covered by a float/orange 100 seconds so get the velocity is 0.5 feet/sec.

2. Throw

The Float in the stream and record the time it takes by using stop watch to

reach the downstream. If the float moves too fast so record the data 75 or 100

instead of 50 feet. Now repeat the process two more times for a total of three

measurements.

Total Width ft x Average

depth ft = area (ft).

1. Using

the total stream calculate the cross-sec area of the stream on the both ends.

To find the total stream width and the average depth.

Measure the distance up to 50 feet along the

bank length.

The main idea is to Measure the time that it

takes a floating object to travel a specified distance in stream downstream. You

can compute the flow of stream. Flow is important because define the size,

shape and direction of the stream.

If a Flow Meter is not Available or Rough

Estimate is enough so you can use the float to determine the flow. The float

can be any light object such as non submergible or an orange or partially

filled plastic bottle.

THEORY:

4) Buoyant

objects such as orange

3) Meter stick To Measure Depth (Tape Measures

are not possible to use)

2) Stop-Watch

or mobile phone having a timer

1) Tape

Measure

APPARATUS:

Determination the velocity & discharge using floats