Asha Beachom, right, takes a water sample under the watchful eye of Dr. Dian Smith, a research scientist with the University of North Texas and the Lewisville Aquatic Ecosystem Research Facility. The water and soil samples will be analyzed for sodium, potassium and phosphates. By the time the water flows through the wetland chain to this spot, about 90 percent of nitrates and phosphates are typically removed by natural processes. The water is then discharged into the Trinity River.