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collected additional flow information. The rainfall volume and intensity for the more recent flow monitoring periods will be compared to rainfall data from the 2005, 2006, and 2007 calibration storms and a recommendation provided as to whether re-calibration is warranted. The calibrated results that were obtained using the RTK method will also be compared to wet weather flow predictions that were generated by SBSA using the regression analysis method. Consultant shall advise the City as to whether use of the RTK approach for the hydraulic model will provide sufficient accuracy in wet weather flow prediction. Consultant shall also review the current calibration results and will refine the calibration if possible, using refined RTK parameters, to reduce any excess conservatism in the hydraulic model. Task 2.3 - Hvdraulic Model Update This task assumes that the data review in Task 2.2 will confirm that the wet weather flow information collected since 2008 will not necessitate an update or re-calibration of the hydraulic model for PVWVF conditions. Also, other than completion of the Manzanita Street trunk sewer upgrade and smaller diameter pipeline replacements, there have been no significant changes in the City's trunk sewers or system operation to require a reassessment of existing system flows. Consultant shall use, as a basis, the existing system hydraulic model that has been validated and calibrated to both dry and wet weather flows (or recalibrated, if needed, in Task 2.2). The Manzanita Street trunk sewer as-built configuration will be included in the updated hydraulic model nefinrork. A review of the currently unmodeled smaller diameter sewers will be conducted to confirm that these sewers are not required within the model to further refine the capacity analysis. It is no longer necessary for the model to be maintained in MIKE URBAN. Therefore, since the original model was developed and calibrated in Innovyze � InfoWorksT"' CS software and then transferred to MIKE URBAN, this update will be completed using InfoWorksT"' CS software. Consultant acknowledges that the terminus of the City's modeled sewer system at the Maple Street Pump Station was modeled as a free outfall. The update will include adding level constraints to the outfall to provide the ability to evaluate backwater conditions that may be created through changes in pum p station operations. Consultant shall amend this updated buildout sewer collection system hydraulic model to reflect anticipated sewer loads based on General Plan water demand data that was developed by Consultant for the Water System model. Task 2.4— Review of Master Plan Capacitv Improvements Consultant shall evaluate the buildout system under the updated PDWF conditions, and resulting PW1NF conditions using the 5-year design storm rainfall event that served as the basis for the Master Plan. The evaluation will confirm that the capital improvement projects presented in the Master Plan are still relevant in light of the updated General Plan projections. The update will also recommend any new projects that are needed to address revised buildout conditions. This proposal assumes that adjustments to up to three of the originally proposed capacity improvement projects may be required. The changes may involve minor changes in size or alignment, or complete replacement of the proposed upgrade with a new capacity improvement project. For this project, and based on the location of projected buildout growth, it is assumed that resulting pump station flows will not be significantly different (i.e., greater than ten percent flow increase) at buildout than predicted in the Master Plan. Therefore, this analysis does not contemplate further evaluation of the City's modeled pump stations. ATTY/AGR/2012.044NVEST YOST ASSOCIATES REV:06-12-12 VR Page 11 of 13