Catawba Wateree Water Management Group 2015 Annual Report

Rhodhiss Nutrient Loading Report

During the 1999-2002 low flow years, both Valdese and Lenoir experienced taste and odor problems in their potable water supply and NCDWQ reported high dissolved oxygen above saturation levels, high pH and high chlorophyll levels. Since that time, no significant taste and odor problems have been noted and water quality levels at the threshold levels have declined.

A proposal to review and analyze the historic nutrient levels (phosphorus and nitrogen) in Lake Rhodhiss, as related to flow, was funded by the Catawba-Wateree Water Management Group (WMG). The proposal’s objectives were to: evaluate the historical nutrient loading and export from Lake Rhodhiss, and, to utilize the historic in-lake data from NCDWQ, Duke Energy, and the USGS for lake nutrient levels as related to nutrient loading and export.

The proposal included a 5-year continuation of a bi-monthly sampling of total nitrogen and total phosphorus in the Rhodhiss tailrace began by Duke Energy in 1997. The tailrace sampling will continue through the summer of 2014. This collaborative effort by the Hickory Pretreatment staff (sample collection), Duke Energy (sample transport, laboratory analysis, historical records of water quality, and historical flow), NCDWQ (historical water quality records) and Carolina Land and Lakes, Resource, Conservation, and Development, Inc. (administration) will result in a comprehensive report in the fall of 2014.