For this lab we visited the Ocmulgee River and measured the depth of the river, the flow rate of the water, and the amount of clams? at various depths.
To measure the depth of the river at various points, or the elevation below the river bank, there were two poles with clearly marked measurements. Attaching the poles was a string with an object attached that helped determine whether the string was parallel to the water line. Two people would each hold a pole and stand at different points across the river. They would then move the string so that it was parallel and record the distance from the string to the height of the water on each pole. The difference of these two measurements would tell how deep one part of the river was in relation to the other.
To measure the flow rate of the water, one person would stand upstream with a floating object. The other person would stand downstream at a particular distance from the first person. The first person would release the object from upstream and someone would use a stopwatch to measure the time it took for the object to reach the person downstream. The flow rate can be calculated by dividing the distance between the person upstream and the person downstream by the time it took for the object to travel downstream to that person.
We also used different sized screens to collect sand and sift through it to find small clams in the river. We were looking to see if there was a higher concentration of clams at a particular depth of the river.