RESIDENTIAL WATER USAGE PART I: Unmetered Single-Family Households Direct Measurements

Transcription

1 RESIDENTIAL WATER USAGE PART I: Unmetered Single-Family Households Direct Measurements Presenting Author: Allan Bronsro, MCIP, P.Eng., Kerr Wood Leidal Associates Ltd. Other Authors: Akemi Siu, B.Sc., Kerr Wood Leidal Associates Ltd., Bill deoreo, MS, PE, Aquacraft Inc.

2 Objective Measure summer water usage by individual, unmetered households.... that are representative of Greater Vancouver - where most houses are billed on a flat annual rate.

3 Project Team Greater Vancouver Regional District Aquacraft Inc. (Boulder, Colorado) Kerr Wood Leidal Associates Ltd. Participating Municipalities City of Richmond City of Surrey City of North Vancouver

4 Indoor Usage in Context (L/person/day) 12-city average 262 Seattle 216 GVRD (indirect measurements) GVRD (this study) 267

5 Methodology Select houses that have meters but are billed on flat rate. Log usage very frequently (every 10 seconds). Use software that recognizes signature of water usage events (Trace Wizard). Follow up with survey.

6 Methodology Cont. Identify Municipalities Identify Potential Sites Data Logging and Manual Meter Reading 2 weeks/10-sec Downloading and Trace Wizard Analysis Develop/Deliver Residential Survey Collect and Compile Survey Results Disaggregate indoor/outdoor water usage Compare Survey and Data Logging

7 Site Selection Criteria Metered Flat-rate billed Accessible meter box Meters less than 10 years old Mixture of lot sizes Meter Box Installation ** Homeowners should not alter usage behaviors during study. **

8 Site Selection Cont. Flat-rate metered homes: New construction Major renovation Watermain upgrades Recent switch to voluntary meter program (BUT, behaviors may be biased)

9 Aquacraft Inc. Brainard Meter-Master data loggers Magnetically driven meters (Neptune, Invensys) Rechargeable 5-minute installation Brainard Meter-Master At 10-second intervals, memory capacity is two weeks.

10 Logger Installations Respect private property. Conduct installations with municipal Operations staff. Be prepared to answer questions - but do not advertise.

11 Logging Results 40 homes logged, 36 produced good traces % success is typical, 5-10% absent owners or meter/logger faults. Manual water meter readings corresponded within 5%

12 Trace Wizard TM Proprietary software developed by Aquacraft Inc. Recognizes signature flow patterns for each type of end usage. Recorded Water End Uses (Typical)

13 Water Event Access Database Sorts water event by: Home Use type Duration (start and end time) Volume Peak flow Mode flow

14 Supplemental Survey Property: lot size, age of home Number of residents Plumbing fixtures: number, type,age Outdoor features: sprinklers, pools, ponds Behaviour: watering practices

15 Indoor vs Outdoor Usage Indoor Usage 41% Outdoor Usage 59% (irrigation) Single Family Summer Water Use (36 GVRD Homes) Indoor Use 41% Outdoor Use (Irrigation) 59%

16 Indoor Water Usage Average Range Per Household 750 L/day 200-1,750 L/day Average Range Per Person 267 L/day L/day

17 Indoor Water Usage Cont. Toilets 81 L/day 30% Faucets 55 L/day 21% Clotheswasher 47 L/day 18% Shower 45 L/day 17% Bath 4.4 L/day 1.7% Dishwasher 2.8 L/day 1.1% Unknown 5.5 L/day 2.1% Leakage 20 L/day 7.8% ** Indoor water use is similar to homes that are billed from metered consumption data.**

18 Indoor Usage in Context (L/person/day) 12-city average 262 Seattle 216 GVRD (indirect measurements) GVRD (this study) 267

19 Comparative Indoor Usage Measured Usage vs 12-City Average Measured Usage (265 L/capita/day) 12-City Average (261 L/capita/day) L/capita/day Toilet Faucet Shower Clotheswasher Bath Dishwasher Leakage Unknown

20 Outdoor Usage 181 irrigation events from 33 of 36 homes. Total volume m 3 over two-week period Lawn watering restrictions - twice per week Possible to determine if watering restrictions are being followed ** Outdoor usage is influenced by price.**

21 Outdoor End Uses Outdoor end uses were not distinguished from irrigation, but may include: Swimming pool filling Car washing Water features Water play

22 What about Sprinkling Restrictions? 4 homes (12%) complied with sprinkling restrictions. These 4 homes used only 1.4% of the total outdoor water. One home used 40% of the outdoor water.

23 Future Work Retrofit plumbing fixtures and re-log. Expand to >100 homes + other municipalities. Use to set/confirm design criteria. Calculate sprinkling efficiencies relative to IR t.

24 Summary Indoor water use of 267 L/person/day, similar to many other cities. Metering appears to affect discretionary usage (outdoor and waste). Disaggregated demand data is needed for rational setting of design criteria - see Part II.

25 Contact Information Allan Bronsro, Kerr Wood Leidal Associates Ltd., or Akemi L. Siu, Kerr Wood Leidal Associates Ltd., or