City of Morgan Hill Sewer System Master Plan 2017

City of Morgan Hill Sewer System Master Plan

TABLE OF CONTENTS

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4.3 JOINT MORGAN HILL – GILROY SEWER TRUNK ........................................4-8 4.4 LIFT STATIONS ..............................................................................................4-8 4.5 FLOW DIVERSIONS .......................................................................................4-11 4.6 SOUTH COUNTY REGIONAL WASTEWATER AUTHORTY WASTEWATER TREATMENT PLANT ......................................................................................4-11 5.0 CHAPTER 5 – SANITARY SEWER FLOWS...................................................................5-1 5.1 FLOWS AT THE SCRWA WWTP....................................................................5-1 5.2 EXISTING SEWER FLOWS BY MONITORING BASIN ...................................5-4 5.3 BUILDOUT WASTEWATER FLOWS...............................................................5-6 5.4 SEWER COLLECTION SYSTEM DESIGN FLOWS ........................................5-6 6.0 CHAPTER 6 - HYDRAULIC MODEL DEVELOPMENT...................................................6-1 6.1 HYDRAULIC MODEL SOFTWARE SELECTION ............................................6-1 6.2 HYDRAULIC MODEL DEVELOPMENT...........................................................6-1 6.2.1 Skeletonization ..................................................................................6-2 6.2.2 Digitizing and Quality Control.............................................................6-2 6.2.3 Load Allocation ..................................................................................6-2 6.3 MODEL CALIBRATION ...................................................................................6-5 6.3.1 Calibration Plan .................................................................................6-5 6.3.2 2014 V&A Temporary Flow Monitoring Program................................6-5 6.3.3 Dynamic Model Calibration ................................................................6-9 6.3.4 Use of the Calibrated Model ..............................................................6-9 7.0 CHAPTER 7 - EVALUATION AND PROPOSED IMPROVEMENTS ...............................7-1 7.1 OVERVIEW .....................................................................................................7-1 7.2 EXISTING SEWER SYSTEM CAPACITY EVALUATION ................................7-1 7.2.1 Existing Peak Dry Weather Flows Capacity Evaluation......................7-1 7.2.2 Existing Peak Wet Weather Flows Capacity Evaluation.....................7-4 7.3 ULTIMATE BUILDOUT CAPACITY IMPROVEMENTS....................................7-4 7.3.1 Butterfield Trunk ................................................................................7-7 7.3.2 Hale-Llagas Trunk .............................................................................7-7 7.3.3 East Dunne Trunk..............................................................................7-7 7.3.4 Hale-Monterey Trunk .........................................................................7-7 7.3.5 Railroad-Monterey Trunk ...................................................................7-7 7.4 JOINT MORGAN HILL-GILROY SEWER TRUNK CAPACITY EVALUATION .7-8 7.5 PIPELINE CONDITION ASSESSMENT ..........................................................7-8 7.5.1 Background and Purpose ..................................................................7-8 7.5.2 Condition Assessment Findings.........................................................7-8 7.5.3 Improvement Recommendations .......................................................7-11 7.6 INFILTRATION AND INFLOW INVESTIGATION IMPROVEMENTS ...............7-16 7.7 MORGAN HILL/GILROY INTERCEPTOR CONDITION ASSESSMENT AND MAINTENANCE PROJECT.............................................................................7-17 7.8 MONTEREY ROAD TRUNK IMPROVEMENTS ..............................................7-18 8.0 CHAPTER 8 - CAPITAL IMPROVEMENT PROGRAM ...................................................8-1 8.1 COST ESTIMATE ACCURACY .......................................................................8-1 8.2 COST ESTIMATE METHODOLOGY...............................................................8-2 8.2.1 Unit Costs..........................................................................................8-2

August 2017

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City of Morgan Hill Sewer System Master Plan