Comparing the Effects of Precipitation and Select Water Quality Parameters in Two Different Suburban Watersheds

Abstract:

Evaluating the water quality of a stream is essential in determining potential sources of impairment and effects of flooding. The amount of precipitation that falls in Dearborn Heights varies depending on the type of weather front producing the rain and how widespread the system is. The Rouge River and the Ecorse Creek are two suburban rivers located in North and South Dearborn Heights. This research sought to investigate the correlation between rainfall type and amount and select water parameters. The water parameters measured included dissolved oxygen, turbidity, conductivity, water temperature and salinity. 40 sets of measurements were taken throughout a period of 5 months, extending from the beginning of July, 2019 to the end of October, 2019. During the investigation period, rainfall amounts often varied with heavy precipitation dropped from thunderstorms to steady rain falling from warm front rain. There were also several periods of extended dry weather. At each river Vernier probes were used to determine conductivity, dissolved oxygen, water temperature, and salinity. However, a water sample from both rivers was taken home to measure turbidity using a Vernier turbidity probe. Comparing rainfall to the water parameters, correlation fluctuated between inverse, direct, or no correlation at all. With much of the turbidity, conductivity, and water temperature measurements, there was a direct correlation between precipitation and the levels of those parameters in the water. However, DO had an inverse relationship with rainfall while salinity had a more variable relationship. Moving forward, we recommend that more areas where rainwater can soak into the ground be created to benefit the health of the rivers and the communities surrounding them.

Key Words: oxygen, salinity, temperature, precipitation, turbidity