BUILDING A RATING CURVE FOR STREAMS IN SPRINGFIELD, MISSOURI

In this study, we used the formula Discharge = Σ (Area x Velocity). For Area, we used the formula Area = (Depth x Width). For measuring Depth, we measured streams during many different conditions. These conditions include Low-Discharge, Medium-Discharge, and High-Discharge. To measure the Depth of the water, we have installed painted height guides in box culverts, and traced a ruler guide on a wading pole. In the stream channel, we moved in increments of two feet subsections for the Width value. For Velocity, we calculated the speed of the water using a mounted pole system with an impeller that counts revolutions. Once calculated, these points were then plotted. Recording data was done on a weekly/bi-weekly basis dependent on precipitation, or lack there of, to record discharge at various levels. Overall, we have created discharge curve graphs with respective R^2 values. However, Springfield Missouri has been part of a drought for much of the project length. At first, much of the data was Low-Discharge, and as a result, the graphs had poor R^2 values. Once more substantial rain storms came through Missouri, our R^2 values improved on our graphs with a much broader range of discharge. The Rating Curves in this study all project between a 0.8-0.9 R^2 value. A Rating Curve can aid future projects by being a tool to quickly measure the discharge of the water and make recording discharge data more simple. Rating Curves from this study can further simplify recording data for similar studies on water quality, locating, and monitoring drainage in Springfield Missouri.