ANALYSIS
Geo 3.5 Internal

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Our hypothesis was that as we travel from the upper reaches to the lower reaches of the river, we expect to find there will be an increase in the discharge from the river. Our data we collected showed a range of what we expected to find as well as some surprise findings.
Rivers channels respond to increases in discharge as the width, depth and velocity change.
Therefore we predicted to find that the maximum capacity of the river would increase as we visited regular intervals down the river. At
Waldron road we found that there was 8.4411 m³/s of discharge. As this was the uppermost site we visited we expected the v olume of flow of water per unit time would be the smallest. However with the results we collected we found that this site had the third highest amount of discharge. To find the discharge we measured the cross sectional area and velocity. We found that the cross sectional area of this site was
12.45m². At this point in the river we expected the channel width to be less than the others as well as the channel depth.
The velocity we expected to be the slowest as a river increases in speed the further towards the mouth. However this was not what we found in our data as the average velocity we measured was 0.678 m/s,
As expected the discharge increased at our next site we visited which was
Kiapapa.
Her the discharge was 9.81825m³/s. As the volume of the water was increasing it also meant the discharge was too increasing. Our cross sectional area of the river increased too 14.25m² showing the increase in depth/width leading to the increased volume of water.The velocity increased from the previous site to 0.689 m/s. We were expecting an increase as the velocity of the river generally increasings the further towards the mouth you travel.
The next site
Puketapu bridge again increased in discharge to 14.7972 m³/s. This river was much wider than the last there was a larger increase in the cross sectional area to 20.9m².
The velocity also increased too 0.708 m/s. The channel of this river was a Braided channel and it often has a high amount of discharge
Our next site
Springfield
was not what we expected to find at all. There was a large decrease in the cross sectional area too 8.225m² which lead to a decrease in discharge. It dropped to
4.81985 m³/s which was the smallest amount of discharge we had come across. We expected to find that the width and depth of the channel would continue to increase