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<br />Consulting Services Agreement between <br />City of San Leandro and RMC Water and Environment—Exhibit A Page 4 of 9 <br />beginning any model runs. This process includes checking network connectivity and data <br />completeness and reasonableness for apparent discrepancies (e.g., negative pipe slopes, outlet <br />pipe invert elevations higher than inlet invert elevations etc.). Missing or suspect data will be <br />resolved to the extent possible through review of available record drawings or field verification. <br />The source of all new or updated data in the model will be documented directly in the model <br />database using InfoWorks “flags” and notes. <br /> Delineate Subbasins and Populate Model. RMC will review and refine (further subdivide) the <br />previous model subcatchment (subbasin) boundaries and assign the model loads and flow factors <br />developed as part of Subtask 4.2 to the subcatchments. <br /> <br />Subtask 4.2 Develop Model Loads and Preliminary Flow Factors <br />This subtask includes the following activities: <br /> Estimates of Existing Wastewater Flows. RMC will review existing parcel, customer billing and <br />water use data, land use type, number and type of dwelling units, etc. that are collected under Task <br />2 to determine the best approach for using this data to estimate existing base wastewater flows. <br />The exact methodology to be used to develop model loadings will depend on the format and <br />completeness of available parcel-based data; however, it is anticipated that EBMUD water use <br />records will be the primary source of data for developing model loads. If sufficient data is not <br />available to generate loadings on a parcel basis, then 2010 census data at the block level may be <br />used for this purpose. Commercial, industrial, and/or institutional users which may contribute <br />significantly greater unit flows than average shall be identified and investigated individually through <br />discussions with City staff. <br /> Estimates of Future Wastewater Flows. RMC will review the City’s General Plan, TOD Strategy <br />and 2010 downtown/BART TOD infrastructure study, and other relevant planning documents, and <br />will coordinate with the City Planning Department staff to discuss specific planning issues and <br />potential growth or redevelopment areas in the City. Using this information, estimates of future <br />wastewater flows based on the type, density, and location of projected future development and <br />redevelopment areas will be developed for a 30 -year planning horizon as specified by the City. To <br />the extent that the information is available, these estimates will be compiled at the parcel level to <br />maximize the accuracy of the data. The projected timing of any growth/redevelopment will also be <br />discussed to provide input on potential phasing of collection s ystem improvement projects <br />identified as part of the Master Plan. <br /> Preliminary Design Flow Criteria. RMC will develop the design criteria to be used to estimate <br />wastewater flows, including unit base wastewater flow factors for residential and non-residential <br />land uses; diurnal base wastewater flow patterns; and infiltration/inflow parameters. These criteria <br />will be developed based on the flow monitoring data from Task 3 plus RMC’s experience with <br />similar Bay Area systems. These criteria will be verified/refined through the model calibration <br />process under Subtask 4.3. <br /> <br />Subtask 4.3 Calibrate Model <br /> Calibrate Model. RMC will run the model under existing conditions and compare the computed dry <br />weather and wet weather flow hydrographs to observed flow monitoring da ta and pump station and <br />treatment plant SCADA data. Modeling parameters such as unit flow rates, diurnal curves, and I/I <br />factors will be adjusted as needed to achieve a reasonable match for modeled to metered flows. <br /> <br />