Running head: RAINWATER HARVESTING IN GRENADA Resident Perspectives on Rainwater Harvesting in Grenada

Running head: RAINWATER HARVESTING IN GRENADA Resident Perspectives on Rainwater Harvesting in Grenada Brian Neff Shelly Rodrego Muge Akpinar-Elci St. George s University Department of Public Health and Preventive Medicine True Blue Grenada Email: Bmail3@gmail.com Abstract: Rainwater harvesting has historically been relatively basic but widespread throughout the Caribbean. Best practices of rainwater harvesting currently is being promoted in Grenada, though adoption is lacking. Past works have focused on the usefulness of the best practices model, not on the factors that facilitate and restrict residential adoption. This study focuses on residential perspectives toward water needs and rainwater harvesting to determine the factors that influence residential adoption of both basic and best practices rainwater harvesting. Surveys were conducted in a community identified in previous work as a target community for rainwater harvesting investment. Results revealed six key factors that influence residential adoption and indicated that the adoption of best practices in the study area is unlikely. Resident Perspectives on Rainwater Harvesting in Grenada Rainwater harvesting has been practiced for thousands of years and remains an important source of water for much of the Caribbean. Methods used to harvest rainwater in the Caribbean are highly variable. In one of the most basic forms, rainwater harvesting involves capturing rainwater runoff from a rooftop in a bucket or barrel. More elaborate, best practices methods incorporate specialized structures including, but not limited to, first flush diverters, filters or screens to prevent organic matter from entering the storage tank or cistern, and post-storage filtration (Caribbean Environmental Health Institute 2009; Caribbean Environmental Health Institute and United Nations Environment Programme 2009; Caribbean Environmental Health Institute 2006). The Caribbean small island developing state of Grenada is located at the southern end of the West Indies archipelago (see Figure 1) and consists of the main island, named Grenada, and two smaller islands with modest populations, Carriacou and Petit Martinique. The current study focuses solely on the main island of Grenada and does not consider the two smaller islands. The island of Grenada covers an area of 311 km 2 and is mountainous, rising to a maximum elevation of 840 m (2,756 ft) and characterized by sharp peaks and jagged ridges (Parsram 2010). The island supports a population of approximately 100,000 people (Government of Grenada 2011). INSERT FIGURE 1 NEAR HERE Due to Grenada s mountainous terrain and location in the path of the northeast trade winds, the island experiences a large amount of adiabatic precipitation and features a tropical rainforest running the length of the island at higher elevations. Annual average precipitation ranges from slightly over 1,000 mm at the northeastern and southwestern coasts to 4,000 mm in the tropical forest interior. Of special significance, the island experiences a dry season from January through May. Interannual variability in the severity of this dry season is high and sensitive to the effects of the El Niño Southern Oscillation (Parsram 2010). The water authority on Grenada maintains a water supply system that delivers piped water to 96.5% of urban residents on the island (Kairi Consultants 2008). The water supply network is constructed to capture water from streams at high elevations, divert the water to a water treatment plant, and then distribute the water to the population, largely by gravity. Due to the mountainous and rugged relief of the island, centralized storage, treatment, and

distribution of piped water is not possible. The water authority maintains a network of 23 surface-water supply catchments and nearly as many water treatment plants scattered throughout the island. Water supply is augmented by eight well fields around the island. Water supply to residents occasionally is interrupted, referred to locally as a water cut-off, for at least three reasons. First, many of the water treatment plants on Grenada lack the capacity to process turbid water, which is common following large rainfall events. In these cases the water treatment plants will simply close. Storage capacity is limited due to the relief of the island and residents are either cut off until the water clears or they receive turbid water. This type of water cutoff generally lasts a day or less. Second, dry season drought conditions often restrict stream flow and less water is available for diversion to water treatment plants. When water demand outstrips water supply, the water authority rations water until conditions change. This type of water cutoff generally lasts between hours to two days, but can be much longer in some cases. Due to both types of water cutoffs, many residents store piped water, or harvest and store rainwater for use during water rationing. Third, natural disasters also threaten water supplies in Grenada. According to Peters (2010), water supply was interrupted following hurricanes Ivan in 2004 and Emily in 2005, causing hardship for many citizens. All three types of water supply interruptions may be exacerbated in coming years by climate change and can plausibly be alleviated by residential rainwater harvesting, leading some authors to point to rainwater harvesting as an important adaptation strategy (Pandey, Gupta, and Anderson 2003). Confirming the value of rainwater harvesting in Grenada, Peters (2010) documented that hardships from water supply interruption in Grenada following Hurricanes Ivan and Emily were reduced for residents that practiced rainwater harvesting. Previous literature estimated that 66% of households on mainland Grenada currently practice rainwater harvesting (Caribbean Environmental Health Institute 2006, p. 15). However, the rainwater harvesting systems utilized tend to be relatively basic. A typical system includes gutters on the edge of a rooftop that funnel rainwater to a repurposed plastic 55 gallon shipping barrel. In contrast to the typically basic approach to rainwater harvesting in Grenada, the so-called best practices model of rainwater harvesting currently is being promoted in many parts of the Caribbean (Caribbean Environmental Health Institute 2009; Caribbean Environmental Health Institute and United Nations Environment Programme 2009). This model is a relatively elaborate approach to harvesting rainwater and supplies potable water suitable for all needs directly into the home. Costs of fitting homes with this technology are estimated by the Caribbean Environmental Health Institute (2009) to range from $556US - $4,037US for homes ranging from one to eight persons, respectively. This estimate is consistent with quotes from Grenadian contractors, who approximate typical costs to be around $2,000 - $3,000US (Alfonso Daniels, pers. comm., 2011), and costs documented for installations on other Caribbean islands (Caribbean Environmental Health Institute and United Nations Environment Programme 2009). As part of ongoing research to establish ways to enhance resident resilience to water shortages, the current project was designed to establish what factors facilitate or obstruct resident decisions to adopt rainwater harvesting. This study is interested in the adoption of traditional, basic forms of rainwater harvesting as well as the best practices model. Method Participants: 89 long-term residents of Grenada who self-identified as a head of a household in Pomme Rose, St. David participated in the current study. This sample size captures approximately half of the total heads of household in the community. The average home size was 3.6 persons (2.2 adults and 1.4 children per home), and the average household income of participants was $3,125US per year, marginally higher than the poverty line of $2,030US and vulnerability line of $2,704US defined by the 2008 Country Poverty Assessment for Grenada (Kairi Consultants 2008). The community has approximately 170-190 homes, based on the author s interpretation of Google Earth aerial images, eight site visits, and consultation with residents and nearby business owners. The community of Pomme Rose was selected because it is specifically identified in the National Rainwater Harvesting Programme for Grenada (Caribbean Environmental Health Institute 2006) as a target community for rainwater harvesting investment (p. 59). Additionally, it was judged to be similar to other target communities during three field visits conducted by the author prior

to the current study. Finally, participants were judged by the surveyor to be intellectually capable of understanding the informed consent process and survey questions. Measures Two surveys were developed by the author for use in the study. The first survey was administered to residents who currently collect rainwater in any way (see Appendix 1). 44 participants completed this rainwater harvesters survey. The second survey was administered to residents who currently do not collect rainwater (see Appendix 2). 45 respondents completed this non-rainwater harvesters survey. The rationale for conducting separate surveys was to capture both the factors affecting the decision to practice rainwater harvesting in general, as well as the factors that affect decisions on adopting the best practices model. Procedure Every home in the Pomme Rose community was canvassed three times during three separate field visits conducted in June and September 2011 and February 2012. All surveys were administered verbally to participants. Surveying was done with the aid of public health graduate students at St. George s University, who were trained and supervised by the author. All respondents provided verbal informed consent prior to answering the survey questions anonymously and no payments were made to respondents. The Institutional Review Board of St. George s University on Grenada reviewed and approved the current project (approval number 11020). Results and Discussion Current rainwater harvesting practices Approximately half (49.4%) of respondents reported practiced rainwater harvesting, somewhat less than found in a previous study that found 66% of homes in all of Grenada practice rainwater harvesting (Caribbean Environmental Health Institute 2006). The rainwater harvesting practices reported by survey respondents were relatively simple, typically involving collecting runoff from a rooftop using a gutter and a single rain barrel or bucket. 88% of rainwater harvesters used a single rain barrel, usually a repurposed plastic 55 gallon shipping barrel, or buckets to store rainwater. 97% of rainwater harvesting homes did not plumb rainwater into the dwelling and the one instance of plumbing rainwater into the home was an opportunistic diversion of rainwater from the home s roof to a tank originally installed to store piped water. Most people who collect rainwater were knowledgeable about how to clean their rainwater harvesting systems and reported doing so periodically. 70% of rainwater harvesters reported knowing how to clean their systems, 54% of rainwater collectors indicated cleaning their systems at least once per year and 74% reported cleaning their systems at least every 5 years. Of those who never clean their rainwater harvesting systems, 88% did not perceive any need to do so. Almost no examples of any element of a best practices model were reported or observed (table 1). No first flush diverters, screened overflow pipes, purification devices, or sanitary means of removing water from the storage tank were observed. Only 38% of rainwater harvesters reported covering their water storage tank or cistern in any way, 16% with a secure cover and 22% with cloth or a screen. One home (3%) reported routing rainwater from the roof to a storage vessel via a closed pipe. INSERT TABLE 1 NEAR HERE: RAINWATER HARVESTING COMPONENTS Survey results also reveal that many residents drink rainwater, often untreated (figure 2). 65% of survey respondents who harvest rainwater report drinking it at least sometimes and 50% drink it untreated at least sometimes. Interestingly, 30% of all rainwater harvesters never treat rainwater before drinking it. When considered across the entire population, these figures translate to 32% of the total population drinking rainwater (treated or not) at least sometimes and 25% of the total population drinking it untreated at least sometimes. 15% of the total population reported drinking untreated rainwater regularly. The public health consequence of drinking rain water remains unclear. Intuitively it seems that pathogens exist in rainwater and drinking it untreated should increase disease prevalence. However, documentation of negative effects in studies remains inconsistent. Peters (2006) reports that waterborne disease related to rainwater is nearly unknown among residents of Carriacou and Petit Martinique, two outlying islands of Grenada that rely on rainwater for 100% of their water supply.

FIGURE 2 NEAR HERE: DRINKING RAINWATER Factors Affecting Rainwater Harvesting Practices Survey results revealed five factors that affect adoption of rainwater harvesting in the target community (table 2). Two of these factors affect the motivation of residents to collect rainwater and three factors affect their ability to do so. All of these factors were worded in such a way that relatively high values facilitate adoption of rainwater harvesting and relatively low values serve to restrict adoption of rainwater harvesting. INSERT TABLE 2 NEAR HERE: SUMMARY OF FACTORS Perceived need. In the study case, the need to collect rainwater was driven by the presence of water cutoffs. Piped water supply to the community of Pomme Rose was characterized as being relatively good, but with frequent water cutoffs or supply of water with unsuitably high sediment content for many residents. Households that collected rainwater were nearly twice as likely (80%) to have experienced water cutoffs than households that do not collect rainwater (42%), a statistically significant difference (χ² = 9.820, p = 0.002). One important factor with regard to the perceived need for harvesting rainwater is the presence of other options for storing water to use during cutoffs. Overall, 61% of all respondents (both rainwater harvesters and non-rainwater harvesters) reported experiencing some type of water cut off. Not coincidentally, 61% of all survey respondents reported storing piped water to help cope with water cutoffs. Of this group, 44.4% did not store water from any other source and 55.6% did store water from at least one other source, usually rainwater. This is interpreted to mean that in the presence of water cutoffs residents will store water from one or more sources, primarily piped water but also rainwater in many instances. Financial incentives. Approximately half (55.6%) of the respondents who reported storing piped water also practiced rainwater harvesting, often as a means to save money on water bills. Nearly 20% of residents that collect rainwater cited the low cost of rainwater as a primary factor in their decision to do so. Many residents report storing piped water inside the home for high quality needs such as drinking, while using rainwater for lowquality/high-volume water needs such as washing clothes. Figure 3 illustrates that 22%-44% of residents prefer using rainwater over all other sources for low-quality water needs such as washing dishes, clothes, and watering plants. FIGURE 3 NEAR HERE: WATER SOURCE FIRST CHOICE Convenience. The first factor that affects the ability of residents to collect and store rainwater is convenience. Table 1 and the associated discussion above describe the very simple rainwater harvesting practices observed in this study. In nearly all cases, rainwater-harvesting setups were makeshift and consisted of materials available nearby and free. Examples include buckets and repurposed plastic shipping barrels used for water storage and scrap pieces of cloth laid across the tops of tanks to serve as a filter and prevent mosquito infestation of stored water. Materials that need to be sourced from afar are conspicuous in their absence, with the exception of gutters, which are present on 65% of homes that collect rainwater. Less than 5% of homes that practice rainwater harvesting had tanks specifically designed for storing water. Financial Cost. The second factor that affects the ability of residents to collect rainwater is financial cost. Households that collected rainwater appeared to be wealthier than residents who do not collect rainwater (table 3). Statistical analysis of the differences between the rainwater harvesters and those who do not practice rainwater harvesting were impeded by very low response rates to income and education questions and a high rate of inconclusive observations of home construction by surveyors. Nevertheless, the mean annual household income of those who collect rainwater was 65% higher than households who did not collect rainwater. Rainwater harvesters were also 60% more likely to live in concrete walled homes and were somewhat better educated than non-rainwater harvesters. Taken together, these indicators may illustrate an importance of possessing some basic level of wealth to access rainwater harvesting supplies. For example, it may be that wealthier residents are more likely to receive shipping barrels from foreign friends and relatives. While wealth may modestly affect adoption of basic rainwater harvesting, it likely serves to make the best practices model completely inaccessible to most or

all residents in the study area. The validity of this factor should be verified in follow-up studies. TABLE 3 NEAR HERE: MEASURES OF WEALTH Knowledge. A third factor that affects resident ability is knowledge and familiarity with rainwater harvesting systems. Basic forms of rainwater harvesting have a long history in Grenada and are widespread. 83% of people who collect rainwater have been using their present systems for over five years and less than 5% of people who do not collect rainwater cite a lack of knowledge as a reason. However, knowledge of the best practices model appeared to be lacking in the study community. No examples of best practices were observed on homes in the study community during any of the field visits. Additionally, respondents who practice rainwater harvesting were asked how they would improve their current system if they could do so in any way. The most common responses were to install gutters (23% of responses), increase storage capacity (18%), and to add a screen or cloth to an existing rain barrel to prevent mosquito infestation (15%). No responses indicated a desire for typical best practices components such as a first flush diverter or a pump and only one respondent (3%) indicated a desire to plumb rainwater into the home. It is apparent that even if other factors were favorable for adoption of best practices, the lack of knowledge of the best practices model would restrict adoption. Implications The results of this study have significant implications for future rainwater harvesting promotion in Grenada. First, I conclude that the possibility of residential adoption of the best practices model of rainwater harvesting in the target community is remote. All five of the factors identified that affect the decision to practice rainwater harvesting are unfavorable to the best practices model in the study community (table 2). In particular, residents in this community are unable to afford best practices systems that cost thousands of dollars, especially when piped water is supplied intermittently and can be stored more easily and cheaply. Results also indicate a limited but significant potential to promote basic forms of rainwater harvesting in the target community, particularly if collecting rainwater can be made more convenient and inexpensive for residents. If this holds true for other parts of Grenada, the significance could be profound. Many parts of Grenada experience dry season piped water shortages and rationing. Often, the dry season demand outstrips dry season supply by a relatively small margin. Promoting basic rainwater harvesting to expand the effective water supply could be far less expensive than expanding capacity at the water authority level. In addition, getting residents to reduce their demand for piped water may be easier by promoting basic rainwater harvesting than by promoting water conservation. These conclusions are consistent with criteria for promoting rainwater harvesting presented by the United Nations Environment Programme (1999) and conversations between the author and persons in the local water authority (Al Neptune, personal communication, 2011). A contribution of this study is to establish data that verify these criteria while providing a detailed picture of the local setting. Limitations This study is limited in a number of important ways. First, Grenada is remarkably diverse, both in terms of water supply and social dynamics. It is possible the results would be different in other towns. Second, this study utilized surveys. This method may be adequate to gauge how and why residents practice rainwater harvesting, but it does a poor job of capturing the best water shortage coping strategy to promote. Third, the subjects of this study are residents and results reflect the biases and limitations of the resident perspective. Other groups of people, notably the local water authority and regional rainwater harvesting promoters, are likely to have valuable input on the matter. Future research could utilize other methods, such as focus groups or interviews, and target the views of other stakeholders to provide a more comprehensive picture of the situation. This would provide a more solid basis for charting a future course to assist residents cope with intermittent piped water supply. Acknowledgements The author acknowledges the gracious assistance of many important people with this study, including: Christopher Cox, Caribbean Environmental Health Institute (CEHI), Alphonsus Daniel of Daniel and Daniel Engineering, Al Neptune, National Water & Sewerage Authority (NAWASA), Jennifer Durst and students at St. George s University.

References Caribbean Environmental Health Institute (2006). National Rainwater Harvesting Programme for Grenada. Ministry of Health, Social Security, Environment and Ecclesiastical Affairs, Grenada. Caribbean Environmental Health Institute (2009). Rainwater Catch it while you can: A Handbook for Rainwater Harvesting for the Caribbean. Caribbean Environmental Health Institute & United Nations Environment Programme (2009). Field Report On Best Practices for Improving Water Quality in Rainwater Harvesting Systems under the project Promoting Rainwater Harvesting in the Caribbean Region - Phase 2. Government of Grenada (2011). Grenada strategic program for climate resilience (SPCR). pp. 112. Kairi Consultants. 2008. Country Poverty Assessment: Grenada, Carriacou and Petit Martinique. Tunapuna, Trinidad and Tobago, West Indies: Government of Grenada. Pandey, D. N., Gupta, A. K., & Anderson, D. M. (2003). Rainwater harvesting as an adaptation to climate change. Current Science, 85(1), 46-59. Parsram, K. (2010). Grenada Water Resources 2010: Centro del Agua para America Latina y el Caribe. Peters, E. (2006). Rainwater potential for domestic water supply in Grenada. Water Management, 159(3), 147-153. Peters, E. (2010). Impact of hurricane Ivan on Grenada water supply. Water Management, 163(2), 57-64. United Nations Environment Programme (1999). Sourcebook of Alternative Technologies for Freshwater Augmentation in Latin America and the Caribbean: The Stationery Office.

Appendix 1 Date Better Rainwater Harvesting Questionnaire Start time 1a 1b Are you a head of household? (one of the people who are primarily in charge in your home) Yes r No r Questionaire ID# How many people, adults and children/youth under 18, live in your home? Adults Youth Total 2a 2b Do you collect rainwater? Yes r No r If yes, go to the "rainwater harvesters" survey Why don't you collect rainwater? (Note to researcher: circle all that apply, but do not read them the list) Piped water is present We store Do not know how Can not afford it Issues with all the time piped water No Reason rainwater safety Home not plumbed for rainwater Other: 3a 3b 3c Do you store other water such as piped or trucked water? (a) Yes r (b) No r (c) I'm not sure r If you do NOT store water to use in the dry season, why not? Can not afford tank No place to put tank Piped water is present all the time If you DO store water to use in the dry season, how large are your storage tank(s) or your cistern(s)? (total) I'm not sure 100 gallons 200 gallons 300 gallons 400 gallons Other Reason: 500 gallons 600 gallons 700 gallons 800 gallons 900 gallons 1,000 gallons 1,100 gallons 1,200 gallons 1,300 gallons 1,400 gallons Note to researcher: circle all that apply, but don't show the list to the respondant 1,500 gallons 1,600 gallons 1,700 gallons 1,800 gallons 1,900 gallons 2,000 gallons 2,100 gallons 2,200 gallons 2,300 gallons 2,400 g or more 4 During the driest part of the dry season, how many consecutive days is your home without piped water? a. No supply interruptions b. 1-3 days consecutive c. 4-6 days consecutive d. 7-9 days consecutive e. 10-12 days consecutive f. 13-15 days consecutive g. 16-18 days consecutive h. 19-21 days consecutive i. 22-24 days consecutive j. 25-27 days consecutive k. 28-30 days consecutive 5 What is your home built from? (a) boards, (b) concrete (c) other Researcher Name: Finish Time: Survey given at homes that do not collect rainwater (page 1 of 1). 12 13 Survey Finished What is your household income? (EC dollars) Monthly or Yearly What is the highest level of education you have attained?

Date 1a 1b 2a 2b 3 a b c d e f g h 4a 4c 5a 5b 5d 5e 6 Drinking Cooking Bathing / personal hygiene Washing dishes Washing clothes Watering lawn/garden Toilet flushing Other (please specify) Appendix 2 Survey given at homes that do collect rainwater (page 1 of 2) Better Rainwater Harvesting Questionnaire Are you a head of household? (one of the people who are primarily in charge in your home) Yes r No r Do you collect rainwater? Yes r (1) Piped into dwelling (2) Piped into yard (4) Hauling Truck (5) Standpipe 4b (6) Neighbor (7)Rainwater (8) Bottled water Your drinking water (from any source)? Do you treat rainwater before drinking it? 4d Rainwater that you use for drinking? (a) Always r (b) Sometimes r Do you clean the parts of your RWH system? (a) Regularly (1x/yr) r No r 4b & 4d: How do you most frequently treat... (9) Surface water (8) Other, specify: (a) boil; (b) Chlorine; (c) UV light; (d) Traditional Filter (eg cloth) (e) store-bought filter (eg Brita); (f) do not treat; (g) Other (specify) Do you know how to clean the parts of your RWH system? Yes r No r Not sure r 5c If not, why not? (b) Occasionally (1x/2-5 yr) r (c) Never r (d) Not sure r Would you clean the system if you knew how? (a) Regularly r (b) Occasionally r (c) Never r (d) Not sure r Would you clean the system if you could do it yourself or afford to hire someone else to do it? (a) Regularly r (b) Occasionally r (c) Never r (d) I don't drink RW r Please describe the parts on your rainwater collection system (You may draw a picture of your system if it helps) (1) I m unsure or only partially sure how my system works (2) Gutters (3) Closed pipe connecting gutter to cistern or water tank (4) Screen or mesh cloth to prevent large particles, mosquitoes and leaves from entering cistern or tank (5) Screened overflow pipe to prevent mosquito entry & breeding (6) Secure cover on cistern or tank to keep out insects & other vermin, dirt and sunshine (7) First flush diverter Start time Questionaire ID# How many people, adults and children/youth under 18, live in your home? Adults Youth Total If no, go to the "non rainwater harvesters" survey If yes, why do you collect rainwater? (Note to researcher: circle all that apply, but do not read them the list) Supply for when piped water is unavailable What is the main source of water for the following uses? (Mark all that apply with an A) What is the source of water when the main source is unavailable? (Mark all that apply with a B) Do you treat your drinking water before use? (a) Always r (b) Sometimes r (c) Never r (c) Never r (d) I don't drink RW r Higher quality than piped water Cost Convenience Other (list): Tastes better than other sources Environmental reasons Note to researcher: Do not show them the list, but let them draw or explain what is on their system and interpret their words for the system components. (8) Extra tank to let sediment settle out before sending water to cistern or main tank (9) Plumbing from tank or cistern into house (10) Pump (11) Access cover to clean tank or cistern (12) A way to get water out of the tank without contaminating it (i.e. A Pump or valve) (13) Other (list or describe)

7a 8 9a 9b Appendix 2 (continued) Survey given at homes that do collect rainwater (page 2 of 2) Better Rainwater Harvesting Questionnaire Page 2 Have you modified your RWH in the last 5 years? (a) Yes r (b) No r (c) Not sure r If you could improve your RWH system in any way, how would you improve it? (1) I'm unsure how I would improve my RWH system (2) Gutters (3) Closed pipe connecting gutter to cistern or water tank (4) Screen or mesh cloth to prevent large particles, mosquitoes and leaves from entering cistern or tank (5) Screened overflow pipe to prevent mosquito entry & breeding (6) Secure cover on cistern or tank to keep out insects & other vermin, dirt and sunshine (7) First flush diverter 7b If you don't store piped water, why not? Why or why not? (Or I have no particular reason) Note to researcher: circle all that apply, but don't show the list to the respondant (8) Extra tank to let sediment settle out before sending water to cistern or main tank (9) Plumbing from tank or cistern into house (10) Pump (11) Access cover to clean tank or cistern (12) A way to get water out of the tank without contaminating it (i.e. A Pump or valve) (13) Other (list or describe) Do you also store piped water? (a) Yes r (b) No r (c) I'm not sure r 9c At most, how many consecutive days is your piped water cut off? a. No piped water cut offs b. 1-3 days in a row c. 4-6 days in a row d. 7-9 days in a row e. 10-12 days in a row f. 13-15 days in a row g. 16-18 days in a row h. 19-21 days in a row i. 22-24 days in a row j. 25-27 days in a row k. 28-30 days in a row 9d 10 Do you store piped water and rainwater in separate tanks/cisterns? (a) Yes r (b) No r (c) I'm not sure r How large are your storage tank(s) or your cistern(s)? (total) I'm not sure 100 gallons 200 gallons 300 gallons 400 gallons 500 gallons 600 gallons 700 gallons 800 gallons 900 gallons 9e 9f 1,000 gallons 1,100 gallons 1,200 gallons 1,300 gallons 1,400 gallons Is your home plumbed to use piped water? (a) Yes r (b) No r (c) I'm not sure r Is your home plumbed to use rainwater? (a) Yes r (b) No r (c) I'm not sure r 1,500 gallons 1,600 gallons 1,700 gallons 1,800 gallons 1,900 gallons 2,000 gallons 2,100 gallons 2,200 gallons 2,300 gallons 2,400 g or more 11 What is your home built from? Researcher Name: (a) boards, (b) concrete (c) other 12 13 Survey Finished What is your household income? (EC dollars) Monthly or Yearly What is the highest level of education you have attained? Finish Time

Table 1 Components of Rainwater Harvesting Systems. Rainwater Harvesting Component Proportion of Systems Gutters 65% Screen or mesh cloth to prevent mosquitoes and large particles from entering cistern/tank 22% Secure cover on cistern/tank 16% Plumbing from tank/cistern to house 3% Closed pipe connecting gutter to cistern/tank Screened overflow pipe to prevent mosquito entry and breeding 3% 0% First flush diverter 0% Extra tank to let sediment settle out 0% Pump 0% Access cover to clean tank/cistern 0% A sanitary way to remove water from the tank (a pump or valve) 0%

Table 2 Factors Facilitating and Restricting Adoption of Rainwater Harvesting. Relatively high values facilitate adoption of rainwater harvesting and relatively low values serve to restrict adoption of rainwater harvesting Factors that affect motivation Basic rainwater harvesting Best practices rainwater harvesting Perceived need Moderate Low Financial incentives Low Low Factors that affect ability Convenience Moderate Low Financial cost Moderate Low Knowledge High Low

Table 3 Measures of Resident Wealth. Measures of Wealth Proportion of homes constructed with concrete walls Households that Harvest Rainwater Households that Do Not Harvest Rainwater Statistical Significance 42% 25% No Annual household income $3,791 US $2,475 US No Proportion of households with one or more members with at least a secondary education 42% 35% No

Figure Captions Figure 1. Map of Grenada. Adapted from images in The World Factbook, by the US Central Intelligence Agency, accessed on 15 March 2012 at https://www.cia.gov/library/publications/theworld-factbook/geos/gj.html. Figure 2. Responses to the question, Do you treat rainwater before drinking it? All 4 options, including I do not drink rainwater were read to the subjects prior to their response. Figure 3. Preferred water source by use. No residents reported using water from a tanker truck, stand pipe, or neighbor.

Figure 1

Figure 2 I don't drink rainwater 35% Always 15% Sometimes 20% Never 30%

90 80 70 60 Figure 3 Piped into dwelling Piped into yard Rain-water Surface water (spring) Bottled water Percentage of Homes 50 40 30 20 10 0 Drinking Cooking Bathing / personal hygiene Washing dishes Washing clothes Preferred Source of Water by Use Watering lawn/garden Toilet flushing