Biennial Drinking Water Plants Survey (DKWP)
Summary of changes
Activity on this program started: 2008
The questionnaire was redesigned so that respondents with multiple water treatment facilities can report the combined total of all their facilities in one questionnaire. In order to align with the Integrated Business Statistics Program (IBSP), an electronic questionnaire (EQ) was used for the first time for the survey. The remaining questions about raw surface water quality were removed.
Respondents are asked to report their best estimate of water use by sector. Two years of capital expenditures are being collected to produce a better time series data set.
Estimation - The estimation system was revised for both 2013 and 2015 for estimating the responding population served for the average daily residential use (persons) and the average daily residential use per capita of the population served (litres per person per day).
Data sources - The use of administrative data to replace or complement survey data is a priority for Statistics Canada. Efforts to achieve this goal involve the Survey of Drinking Water Plants where respondents in Québec are not surveyed by Statistics Canada. Instead, the data are collected by an existing survey administered by the Ministère des Affaires municipales, des Régions et de l'Occupation du territoire and the results are shared with Statistics Canada.
Data accuracy - With the change in data collection for Québec respondents, comparisons from a time series perspective should be made with caution.
Collection instrument - The revised 2013 questionnaire was not tested because the only changes made were to remove or restrict the scope of some questions.
The primary differences between the 2013 questionnaire and the previous one are as follows:
- the raw/source water quality section was restricted to surface water only
- the data collected in the raw/source water quality section was reduced to three monthly parameters, and annual data is no longer collected.
Instrument design - The revised 2011 questionnaire was tested in both official languages in the fall of 2010 at 9 locations (5 in Ontario and 4 in Québec).
Collection instrument - The primary differences between the 2011 questionnaire and the previous one are as follows:
- one year of data was collected instead of three
- questions on the use of water by sector were added
- the number of parameters in the raw/source water quality section was reduced, and annual instead of monthly data were requested for the majority of them
- all questions on treated/potable water quality were removed