Sargent Creek Nutrient Injection Breakthrough Curve

Abstract

Breakthrough curve data from nutrient injection tracer tests conducted at Sargent Creek on 2021-09-15 and 2021-09-22. The tests were conducted in two stream reaches, the treatment reach which was restored with a full channel realignment in 2019 and the control reach which was not restored. These tracer tests were conducted as part of an effort to assess the effects that restoration practices have on a stream ecosystems. A solution of nutrients (Potassium Nitrate (KNO3), Ammonium dihydrogen phosphate ((NH4)H2PO4)) and a conservative tracer (Sodium Chloride (NaCl)) dissolved in stream water was injected into the stream at the top of the reach as an instantaneous release. Water samples were collected in the thalweg at downstream end of the reach to describe reach-scale nutrient spiraling. Additionally water samples were collected at two sites located mid-reach at the upstream and downstream end of a representative riffle type habitat unit to describe the nutrient cycling within these individual habitat units. Timing of sampling was determined by a conductivity meter in order to capture rising, peak, and falling concentrations and generate a breakthrough curve (BTC).