City of Kelowna Wastewater Master Plan Update

Transcription

1 City of Kelowna Wastewater Master Plan Update 44th BCWWA Annual Conference & Tradeshow May 2, 2016 Urban Systems Ltd. Jeremy Clowes, P.Eng. GeoAdvice Engineering Inc. Werner de Schaetzen, Ph.D., P.Eng. 1

2 Presentation Outline Model Development Model Calibration Hydraulic Capacity Analysis Modeling Lessons Learned Results Proposed Upgrades and Estimated Costs Conclusion and Recommendations Questions 2

3 Introduction Urban Systems and GeoAdvice updated the City s master plan in 2015 Original plan was prepared in 1997 Main objectives of the update were to: Convert to a new software to allow for dynamic simulation Update and calibrate model Review most current growth projections Identify costs to address capacity deficiencies over 50 year planning horizon 3

4 Infrastructure Overview The City has: 572 km of gravity sewers 21 km of forcemains 34 lift stations 2 treatment plants 4

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6 Modeling Tool Utilized to Evaluate Options and to Identify Likely Hydraulic Restrictions in the Sanitary System Computer Representation of the City of Kelowna, BC Sewer System using InfoSWMM Why? Predict how the system will perform under stress Predict how the system will perform in the future Evaluate options and return on investment before committing funds 6

7 InfoSWMM Software Innovyze GIS environment (ArcGIS) Open channel flow and pressurized flow Assumptions: Hydrograph Flow attenuation Pipe storage Dynamic simulation EPA SWMM Version 5.0 Convert existing InfoSewer model to InfoSWMM 7

8 GIS vs. Model GIS Geospatial database with coordinates Polygons, lines and points Facility general locations Access to other data sets Model Manhole, wet well, gravity main and pump Operational control rules and temporal variables Load area polygons and connectivity Model updated from GIS 8

9 Field Data Collection Validate System Loadings Estimate groundwater inflow Validate sanitary loads allocation and distribution Establish the 24-hour diurnal flow Review Peak Wet Weather Flow Assess Rainfall Dependent Inflow and Infiltration Calibrate/Validate the Model Enhance Understanding of the System High Value for Minimal Investment 9

10 Field Data Collection Program 7 sites monitored throughout collection system for approx. 2 months 10

11 Model Development Import/Update InfoSewer Model: Allow for dynamic analysis Add about 70 km of new sanitary mains Loading Assumptions: Metered Parcels: City consumption records Unmetered Parcels: Rates adjusted to match Raymer flow records SF Residential Growth: 250 L/d/cap, MF Residential Growth: 230 L/d/cap ICI Growth: 150 L/d/cap Special cases: Kelowna General Hospital and YLW I&I Assumptions: Pipes within water table: 8,000 L/ha/day Pipes above water table: 5,000 L/ha/day 11

12 Model Calibration Confidence: Demonstrate the model s ability to reproduce existing conditions. Understanding: Confirm the understanding of the performance of the system. Trouble Shooting: Uncover missing information and misinformation or anomalies about the system. 12

13 Average Hourly Flow (L/s) Average Hourly Flow (L/s) Average Hourly Flow (L/s) Average Hourly Flow (L/s) Model Calibration Results Flow Monitoring Site #1 - Calibration Results Flow Monitoring Site #2 - Calibration Results Hour Hour Field Data Model Flow Field Data Model Flow Flow Monitoring Site #3 - Calibration Results Flow Monitoring Site #4 - Calibration Results Hour Hour Field Data Model Data Field Data Model Flow 13

14 Average Hourly Flow (L/s) Average Hourly Flow (L/s) Average Hourly Flow (L/s) Average Hourly Flow (L/s) Model Calibration Results Flow Monitoring Site #5 - Calibration Results Flow Monitoring Site #6 - Calibration Results Hour Hour Field Data Model Data Field Data Model Flow Flow Monitoring Site #7 - Calibration Results Raymer WWTP - Validation Results Hour Hour 14 Field Data Model Flow Field Data Model Flow

15 Model Calibration Limitations Sources of errors Input data errors System loading errors Elevation errors Operational control errors Poorly calibrated measuring equipment Outdated data 15

16 Modeling Lessons Learned -1- Model = Approximation of real world Dynamic simulation provides significantly more accurate results than that of steady-state simulation Most work involves data collection/checking GIGO: Garbage In = Garbage Out Good calibration leads to good decisions Always check modeling results to make sure they are reasonable Informed decisions save time and money 16

17 Modeling Lessons Learned -2- Modeler will interact with Senior Management Operations Engineering Planning Do you have these parties identified? 17

18 Modeling Lessons Learned -3- Modeling Practice Data Entry Frequent checking Trial runs to show major data entry errors Plan runs before you make them Try different scenarios and alternatives Keep good records Modeling Standards Modeling is an Iterative Process 18

19 Hydraulic Capacity Criteria Gravity Mains Criteria d/d HGL Velocity 19

20 Hydraulic Capacity Criteria (Continued) Criteria Lift Stations 20

21 Hydraulic Capacity Criteria (Continued) Criteria Lift Stations 21

22 Hydraulic Capacity Criteria (Continued) Criteria Forcemains 22

23 Hydraulic Capacity Criteria (Continued) Criteria Raymer WWTP Treatment Capacity => ADWF and AWWF Hydraulic Capacity => PWWF 23

24 Analysis Scenarios: Deficiency and Sizing Scenarios Scenarios Evaluated Existing System with: 2014 Population (194,000 people actual and equivalent) 2020 Growth (+23,200 people actual and equivalent) 2040 Growth (+76,000 people actual and equivalent) Recommendation Sizing Scenario: 2070 Growth (+149,000 people actual and equivalent) 24

25 Hydraulic Capacity Results Existing Gravity Main Capacity Analysis 25

26 Hydraulic Capacity Results (Continued) 2020 Gravity Main Capacity Analysis 26

27 Hydraulic Capacity Results (Continued) 2040 Gravity Main Capacity Analysis 27

28 Hydraulic Capacity Results (Continued) Lift Stations Pump Station 2014 HLos Rating 2020 HLos Rating 2040 HLos Rating Airport Lift Station D E E Gyro Lift Station A E E Hillsborough Lift Station A A D Highway 97 Lift Station A D D 28

29 Hydraulic Capacity Results (Continued) I&I Analysis Observed rates consistent with City s design rates 5,000 L/d/ha pipes not in water table 8,000 L/d/ha pipes in water table Reasonable target for I&I is 11,200 L/d/ha (refer to 2003 FCM Guideline) Current level of I&I is reasonable 29

30 Hydraulic Capacity Results (Continued) Raymer WWTP WWTP Components Mechanical Screens Raw Sewage Pump Station Grit Chamber Primary Clarifiers Bioreactors Secondary Clarifiers Tertiary Filters UV Disinfection Outfall SCENARIO Existing L/s MLD L/s MLD L/s MLD L/s MLD L/s MLD L/s MLD L/s MLD L/s MLD L/s MLD Existing ADF Treatment Capacity n/a n/a n/a n/a Existing MDF Treatment Capacity n/a n/a n/a n/a Existing Hydraulic Capacity ADF = 470 L/s, 41 MLD AWWF = 858 L/s, 74 MLD PWWF = 971 L/s, 84 MLD ADF = 526 L/s, 45 MLD AWWF = 907 L/s, 78 MLD PWWF = 1038 L/s, 90 MLD ADF = 654 L/s, 57 MLD AWWF = 1049 L/s, 91 MLD PWWF = 1198 L/s, 104 MLD ADF = 830 L/s, 72 MLD AWWF = 1206 L/s, 104 MLD PWWF = 1371 L/s, 118 MLD Notes: ADF = Annual average day flow MDF = Max day flow AWWF = Max day wet weather flow PWWF = Peak hour wet weather flow Deficient Deficient Deficient Deficient Deficient Deficient Deficient Deficient Deficient Deficient Deficient Deficient Deficient Deficient 30

31 Design Criteria for Sizing Proposed Gravity Mains Criteria Sizing Scenario Parameter Value 2070 PWWF Maximum d/d ratio d/d < 0.50 Hydraulic Grade Line Minimum Velocity Material HGL < Ground elevation v > 0.75 m/s PVC Roughness Coefficient Manning n = Minimum Diameter (Residential) Minimum Diameter (ICI) Slope 200 mm 250 mm Assume same slope as existing gravity main 31

32 Proposed Upgrades Infrastructure Upgrade Recommendations: Infrastructure Upgrade Recommendation Gravity Mains 6.5 km Forcemains 1.2 km Lift Stations 3 Comparison of InfoSWMM/InfoSewer Recommendations: Software InfoSWMM InfoSewer Recommendations 6.5 km of Gravity Mains 24.1 km of Gravity Mains 32

33 Proposed Upgrades (Continued) Gravity Main Upgrade Staging Scenario Pipe Size Range (mm) Pipe Length (km) Existing 375 to to to $14.3M total estimated cost for proposed pipes 33

34 Proposed Upgrades (Continued) Lift stations Item Description Cost Scenario Triggering Upgrade 1 Airport Lift Station Upgrade $809, Gyro Lift Station and Forcemain Upgrade $1,840, Hillsborough Lift Station Upgrade $653, Subtotal $3,302,000 Engineering and Contingency $1,321,000 Total (rounded) $4,623,000 34

35 Proposed Upgrades (Continued) Raymer WWTP Upgrade Schedule Scenario Upgrade Reason rd mechanical screen to be provided. For redundancy Primary clarifiers to be upgraded to accommodate 2070 flows Bioreactors to be upgraded to accommodate 2070 flows Secondary Clarifiers to be upgraded to accommodate 2070 flows Tertiary Filters to be upgraded to accommodate 2070 flows UV Disinfection System to be upgraded to accommodate 2070 flows. Treatment Capacity exceeded under AWWF Treatment Capacity exceeded under AWWF Treatment Capacity exceeded under AWWF Treatment Capacity exceeded under AWWF Treatment Capacity exceeded under AWWF 35

36 Proposed Upgrades (Continued) Raymer WWTP Item Description Cost Scenario Triggering Upgrade 1 Mechanical screen to be installed $238, Stage 2 Phase 2 expansion to be completed $24,169, Subtotal $24,407,980 Engineering and Contingency $13,026,620 Total (rounded) $37,450,000 36

37 Recommendations Complete flow monitoring for proposed developments Complete flow monitoring for all DCC and capital projects Install 2 additional permanent flow monitoring stations Integrate capacity driven upgrade needs with condition related upgrading needs 37

38 Thank You Questions? Contact GeoAdvice Engineering Inc. - Werner de Schaetzen Phone: [email protected] Urban Systems Ltd. - Jeremy Clowes Phone: [email protected] 38