Klamath Lake Drainage: A Basin Scaled Multiple Parameter Analytical Effort

The Klamath Lake drainage covers 9,800 km2 over a varied landscape that drains mountainous headwaters with flows converging to the arid high desert setting of Klamath Lake, Oregon. Roughly 70% of the basin is forestlands, with 14% rangelands commonly used for cattle grazing, 6% natural wetlands, 6% used for cultivated agriculture and the remaining 4% inundated by water (i.e. Crater Lake and Klamath Lake). The basin is home to several extensive meadow and wetland complexes that offer unique water quality influences and can also become sources of nutrient and other pollutants when degraded by agrarian and forestland uses. The most sensitive beneficial uses are primarily threatened and endangered fisheries comprised of bull trout (Salvelinus confluentus), redband trout (Oncorhynchus mykiss), Lost River sucker fish (Deltistes luxatus) and shortnoss sucker fish (Chasmistes mykiss). These fisheries are highly valued by the Klamath, Modoc and Yahooskin Tribes and tribal members strongly associate with the lands and natural resources of the basin. Other stakeholders include ranchers, foresters, irrigators and urban areas. Streams and rivers range from high water quality to extremely poor water quality. 303(d) listings addressed in the TMDL are extensive: 692.5 river km for temperature, 164.2 river km for pH and dissolved oxygen and 267.3 lake km2 for pH, chlorophyll-a and dissolved oxygen. A large scaled TMDL, like the one developed for Klamath Lake and its drainage, presents numerous challenges: different land management and ownership patterns, a mixture of nonpoint sources, various point sources, multiple water quality parameters of concern, numerous beneficial uses or water, endangered species, varied landscapes, atmospheric and hydrologic parameters and layers of local, state and federal authorities. A common interest for all parties was to optimize the analytical underpinnings of the TMDL and implementation planning.To meet these challenges, the TMDL utilizes data collected bi-weekly over the past decade, multidisciplinary data analysis and research and integrates GIS based analytical modeling. Remotely sensed thermal infrared (TIR) data, near infrared satellite imagery, long with other data sources (i.e. rectified digital aerial photography, digital elevations models, water withdrawal information, etc.) are extensively used in the analysis that spans traditional modeling, statistics, and GIS based watershed scaled surface water modeling. While considered large by any measure, the TMDL was developed foremost to establish scientific credibility, offer practical water quality management options, and withstand political ad social pressures inherent to the basin that is often protective of the local resource based economy. The TMDL was approved by EPA Region X in August, 2002.