Public Opposition to Upcoming Water Supply Scheme and Perception on Groundwater
5.2 Methodology
In order to understand the rationale for public dissatisfaction/opposition/protest towards the water supply scheme, review of documents published for the study area has been carried out.
Further, public knowledge and perception on quality of groundwater and WtP from water supply scheme has been assessed through a questionnaire survey and analyzed through cross table approach. The necessary and adequacy of representative samples to be collected from a locality has been determined statistically.
5.2.1 Questionnaire Development
The questionnaire survey method is an effective tool to assess characteristics and actions/opinions of a large group of people (Creswell, 2009). Hence, it was adopted for this study and questions were so developed that it should gather requisite information, should be quickly answerable and should be simple to understand. Apart from collecting demographic information (name, age, gender, etc.), the questionnaire survey primarily aimed to gather information on four parameters viz. public perception on household groundwater quality, knowledge on health effects of contaminated water consumption, knowledge/familiarity over upcoming water supply scheme and WtP. In development of questionnaire, a five level Likert scale was initially adopted for most of the question to allow the respondents to respond on the degree of agreement. The scale does not force the respondent to take a stand on a particular topic but had to indicate their level of agreement with a given statement (Croasmun & Ostrom, 2011). The preliminary questionnaire developed is presented in Table A.1, Appendix. A total of 15 households were selected randomly in the study area for the responses. However, it had been observed that most of the questions were pertaining to whether the respondents have observed the ill-effects of the contaminants or not. In such a case, the responses were expected to be either yes or no. Thus, the preliminary questionnaire was modified by replacing the questions with binary responses. Many researchers have claimed that binary answer formats were easier and quicker for respondents to respond than that of Likert scale formats (Dolnicar et al., 2011; Grassi et al., 2007; Hauser & Koppelman, 1979). The revised questionnaire was then used for the pilot study (Appendix, Table A.2).
5.2.2 Pilot Study with Questionnaire Survey
Pilot studies are the feasibility studies that are small in scale or trial run carried out in preparation for a major research (Polit et al., 2001). It helps to identify whether the study is aligned with the research question. And, the flaws, simplicity and clarity of the questionnaire could also be well understood and determined (Walker, 1997). While interviews were conducted in pilot study, questionnaire were checked for the design and format, its length and output, requisite data and its role in the analysis (Flowerdew & Martin, 2005) for a small sample of households before undertaking main data collection task (Hassan et al., 2006). Hill (1998) and Isaac & Michael (1995) suggested a sample size of 10 to 30 respondents for a pilot study in survey research. However, in medical field, Julious (2005) reiterated that a minimum of 12 subjects per group be considered for pilot studies. Treece and Treece (1977), referring to piloting an instrument, noted that for a project 10 respondents should be a reasonable number; while Creswell (1998) suggested 5 to 25 response as sufficient. As a part of the pilot study in our research, 20 households were selected randomly in the study area. The household respondents varied in age, gender, years of living in the area, educational level, and experience. This gave check and assurance over accurate collection and meaningful analysis of the data (Kometa et al., 1995). Furthermore, pilot study was to help improve questionnaire in aspects of gathering information, quick answerability and understandability with public feedback.
Using the questionnaire (Appendix, Table A.2), the household respondents were interviewed in face to face format and this questionnaire was further modified from time to time based on their feedback. Some of the important feedback were difficulty in understanding the questions and presence of repeated questions. Some participants even suggested on shortening the length of the questionnaire to shorten interview duration and become more appealing. These feedbacks were taken into consideration and most of the questions were rephrased/rewritten. The final questionnaire, thus, developed after the pilot study is shown in Table A.3, Appendix. The final questionnaire contained seven sub-parameters under three categories with 28 questions in total.
The questions were either having multiple choices or dichotomous type (with yes/no response).
The first category included 8 questions on demographic information. Rest of the 20 questions were related to household groundwater quality, WtP from the scheme, scenario of household water
water supply scheme. The focus and objectives of this perceptions about groundwater was conducted on household residents who were asked about their perceptions and concerns about drinking groundwater quality and groundwater related health issues. Understanding user perception of drinking water can contribute to improvements in water management and consumer satisfaction.
5.2.3 Sample Size Determination
The study area i.e. South-West Guwahati was divided into 13 municipal wards and 4 peri- urban zones. The wards were assigned by the municipality but the zones were newly included under the municipality and no ward number is assigned yet. The ward/zone of South-west Guwahati was plotted using ArcGIS 9.3 as shown in Figure 5.1. The population distribution in these wards/zones was found to be uneven due to presence of hills, marshy lands and irregular land use pattern as a result of migration/rapid increase of population. Based on the number of households in each of the wards/zones, the number of samples to be collected from each of the ward/zone for questionnaire survey and water sample collection were determined. The representative sample size for individual ward/zone was determined using Eq. 5.1 (Rammont &
Figure 5.1: Location map of South-West Guwahati with its wards (W) and zones (Z).
Amin, 2010) and represented in Table 5.1.
n
=
NZ2p1- p
Nd2+Z2p1-p (5.1) where,
n = sample size of household for questionnaire survey and water sample collection
N = number of household
Z = value corresponding to confidence interval level (1.96 for 95%
confidence level)
p = estimated population proportion (assuming to obtain the maximum value, p = 0.5) and
d = precision (assuming 10% precision).
However, the sample size is not directly proportional to the number of households and reaches plateau after certain household number. Various authors have also presented non- requirement of higher sample size with higher number of households (Bartlett et al., 2001; Walker
& Almond, 2010). The variation of the sample size in present investigation is plotted in following figure for your kind reference and perusal. It changes gradually from 100 to 5000 but does not change much for households larger than 5000 (Table 5.2).
Table 5.1: Number of sample size of household for questionnaire survey and water sample collection for each ward/zone
Ward/Zones No. of
households Sample size Ward/Zones No. of
households Sample size
W1 3598 94 W10 2336 92
W2 3671 94 W11 4251 94
W3 2609 93 W12 9055 95
W4 2617 93 W13 6663 95
W5 3076 93 Z1 609 83
W6 2372 92 Z2 1385 90
W7 4647 94 Z3 3174 93
W8 1715 91 Z4 1919 91
W9 1580 91
Table 5.2: Change in sample size corresponding to number of households