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To use P8 to its full potential, several different types of field information are required. However, we propose to collect some of this information specifically for this project, through the following efforts: Collect, Review and Evaluate Storm Water Runoff Monitoring Data Three storm water inflow locations will be monitored at major inflow sites during the 2007 water year (Oct 06 -Sept 07) by RWMWD staff. The monitoring data will be used to calibrate the P8 model for both water and pollutant loading (total suspended solids and total phosphorus) from the lake's watershed. ® Review and Evaluate Available Precipitation Data Available data from precipitation gauges in the vicinity of the Lake Owasso watersheds will be evaluated for use in the P8 model. Conduct a Field Survey of all Significant Ponds and Wetland Areas Within Each Subwatershed The storm water quality treatment provided by upstream ponds and wetland areas is important to the water quality of the downstream lake. During a storm, polluted runoff enters the ponds and displaces "clean" water until the plume of polluted-runoff reaches the pond's outlet structure. When the runoff does reach the outlet, it will have been treated by the settling of sediments and, in some cases, the biological uptake of nutrients. Therefore, the treatment effectiveness of a pond is directly correlated with the volume of its permanent pool, also lciiown as the "dead storage volume." A survey of the ponds and wetland areas in the lake's subwatersheds will be conducted by Barr staff in order to determine the dead storage volume of each of the water bodies. The survey involves measuring the perimeter of each pond, standing water depths at various locations in the pond, the overflow point, and outlet sizes, types and relative elevations. Barr proposes to survey up to 14 ponds throughout the Lake Owasso watershed. The data collected in the survey will be processed using GIS technology to generate the dead storage volume of each pond in the lake's tributary watersheds. Create GIS land use coverages representing current and future conditions for the Lake Owasso tributary watershed. Two different land use scenarios (current and future) will be modeled using P8. The existing conditions model will be developed for the purposes of calibrating the in-lake model. The future (i.e., ultimate development) conditions model will be used to assess the attainability of the beneficial use water quality goals and to analyze alternative remedial measures. P:\wr\13\pip\2006\6069 -Lake Owasso\Lake_Owasso_UAA_Scope_Final_Jan 12 07.doc