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This experiment focused on the question; to what extent does nitrate, pH, temperature, and dissolved oxygen affect the biodiversity of macroinvertebrates? The hypothesis states that if over time, dissolved oxygen levels are high, nitrate is less than 1 ppm, pH levels are neutral, and water temperature is between 14 degrees Celsius and 20 degrees Celsius, then the population of macroinvertebrates will be more diverse because these conditions promote more food sources and varied habitats for the most macroinvertebrate species. The independent variable is time. The dependent variables measured are nitrate in parts per million, pH, water temperature in Celsius, dissolved oxygen in parts per million, and the biodiversity of macroinvertebrates. The controls for this experiment are the time of observation, the study site, the testing equipment, and the GLOBE protocols. This experiment was conducted by using LaMotte Dissolved Oxygen and Nitrate kits, a Jellas pH meter, and an alcohol filled thermometer to measure water quality parameters and collecting macroinvertebrates according to GLOBE Protocols. The data partially supported the hypothesis. This is because the data showed moderately high dissolved oxygen, pH close to neutral, and water temperature closer to 20 degrees Celsius promoted more biodiversity. It seemed these levels were more optimal for the most amount of classifications of macroinvertebrates, including pollution sensitive, moderately sensitive, and pollution tolerant. If this experiment would be continued, there would be more data collected after precipitation events. Keywords: water quality, nitrate, dissolved oxygen, pH, water temperature, macroinvertebrates, biodiversity