Res 2022-154R/approving a professional services agreement with Freese and Nichols, Inc. for an update to the City’s Wastewater Master Plan in the not to exceed amount of $696,480.00

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Attachment SC curves and controls,and reassess additional model parameters such as manning's N values and force main roughness coefficients. Utilize water billing data to spatially allocate wastewater flows to the model. C6. Diurnal Pattern Development: Review the wastewater flow monitoring data to develop diurnal patterns for each flow meter basin. Diurnal patterns will be determined by isolating flow meter data from dry weather periods to characterize the hourly pattern of how flow is conveyed to the wastewater collection system. Import diurnal patterns into hydraulic model. C7. Model Calibration: Perform model simulations and compare with field measured data to identify gross deviations from field measurements potentially indicative of blockages or pipe sizes and grades differing from GIS mapping records. Following any efforts to resolve blockages and network model errors, calibrate the hydraulic model for dry and wet weather conditions by adjusting antecedent conditions,per capita flows,diurnal curves,lift station operations,inflow and infiltration volume,timing of flow response,and runoff area. Hydraulic analyses performed within the Hemphill and Blanco basins in support of the Highway 80 Lift Station design project and Lift Station 14 capacity assessment will be incorporated into the model calibration process. Smart Cover and other collection system performance data collected bythe City will also be used to aid in model calibration. C8. Progress Meeting#2: Attend and facilitate a meeting with City to review flow monitoring data and model calibration results. C9. Model Calibration Technical Memorandum: Prepare a Technical Memorandum summarizing the flow monitoring and model calibration process.An electronic PDF file of the Technical Memorandum will be submitted to the City. Comments or edits to the memorandum will be incorporated into the Master Plan report. Task D: Risk Based Assessment for Linear Assets and Key Lift Stations D1. Develop Desktop Risk Based Assessment: Evaluate existing risk models catalogued in the Condition/Criticality Dashboard maintained by the City. Interview the City's operations staff to collect soft data based on recollection and perception.Where condition scoring does not exist in the City's dataset, identify and analyze available hard data sources (e.g. address-based main break, backup, overflow, blockage, and repair records cross-referenced by pipe type, age, diameter, and slope for mains; overflow, mechanical failure, power loss, flooding, and structural defect cross- referenced by lift station location,age,capacity,and connections served for lift stations)from which the condition of major buried assets or asset groupings, and pumping facilities can be ascertained. D2. Evaluate Risk Scores: Review likelihood of failure classifications based on condition assessment considering all available data sources and update if needed. Review the City's methodology to assess the consequence of failure and confirm or modify existing risk scores for major assets and asset groupings. D3. Develop Wastewater Renewal Projects: Renewal (i.e. repair, rehabilitation, replacement) projects will be developed based on asset risk scores, evaluation of renewal projects on the City's current 5- year CIP,and the input and recollection of City operations and maintenance personnel. Coordinate development of renewal projects with scheduled capacity projects. Page 3 of 8