City of Morgan Hill Sewer System Master Plan 2017

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City of Morgan Hill
Sewer System Master Plan
TABLE OF CONTENTS PAGE NO.
August 2017 ii City of Morgan Hill
Sewer System Master Plan
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
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
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.
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.
8.1 COST ESTIMATE ACCURACY .......................................................................8-1
8.2 COST ESTIMATE METHODOLOGY...............................................................8-2
8.2.1 Unit Costs..........................................................................................8-2