Poster Presentation Society for Freshwater Science 2025 Annual Meeting

Breaking ground: The impact of construction on nutrient loads in urban streams (117867)

Matthew B. Wilson 1 , Shannon L. Speir 1 , Alana G. Strauss 2 , Caroline G. T. Anscombe 1
  1. Department of Crop, Soil, and Environmental Science, University of Arkansas, Fayetteville, AR, United States
  2. Division of Agriculture, University of Arkansas, Fayetteville, Arkansas, United States

Degradation of water quality is primarily caused by human activities, such as urbanization. Urban Stream Syndrome (USS) can be characterized by the  negative physical, chemical, and biological changes to water quality as a result of urbanization. One key effect of USS is the input of excess nutrients, which can drive unwanted macrophyte and algal growth. New construction is prevalent in urbanizing areas, resulting in the influx of nutrients, sediments, and other materials into stream ecosystems; however, few studies have examined the impacts of active construction on water quality. As such, we do not understand how construction affects nutrient transport downstream. Here, we studied the impacts of construction on urban water quality in Tanglewood Branch in Fayetteville, Arkansas, which originates from a spring below an ongoing construction project. We measured soluble reactive phosphorus (SRP) and nitrate (NO3-) concentrations and discharge, at five sites downstream of the construction biweekly.  We calculated instantaneous nutrient load and examined spatiotemporal variation. Preliminary findings show that SRP and NO3- loads decrease moving downstream of the construction, suggesting that in-stream biota are removing SRP and NO3- from the water column during transport. This study will increase our understanding of construction projects on water quality and assist in determining if municipalities may need to consider stricter construction regulations to restrict unwanted nutrients from entering surface waters.