HOUSE TYPES AS INDICATOR OF HOUSEHOLD WELFARE, DOMESTIC WATER SUPPLY AND SANITATION IN A CRAFT VILLAGE IN NHUỆ-ĐÁY RIVER BASIN

S. GROTHE¹, R. EMMERICH¹, W. STEINGRUBE¹, J. KASBOHM^1&2, P. KRASKA³

¹ Institute of Geography, University of Greifswald, Makarenkostraße 22, 17487 Greifswald, Germany
² GeoENcon Ltd., TZ Vorpommern, Brandteichstr. 20, 17489 Greifswald, Germany
³ Architect, Thomas-Müntzer-Platz 57, 18057 Rostock, Germany

Abstract: The present study examines 3 house types for differences in welfare, domestic water supply and sanitation of households in a craft village situated in the Nhuệ-Đáy river basin. Extensive and time-consuming microdata surveys are needed to procure household data, which are necessary for sophisticated municipal water management planning on communal level. Findings of this study show that house types contain useful informational values concerning the socio-economic situation and the state of household based water supply and sanitation. It was figured out that permanent housing units with all basic facilities (type A) and semi-permanent housing units (type C) differ substantially according key parameters. Permanent housing units without all basic facilities (type B) reflect a transitional state of household living standard. Type A houses accommodate households with significantly higher income. Remarkably higher shares of municipal tap water connections and flushing toilets in house type A cause a significantly higher tap water consumption compared to households residing in both other house types. In house type B and especially in house type C local water sources and dry toilets are widespread.

I. INTRODUCTION

Microdata on socio-economic situation, water supply and sanitation are a cornerstone of municipal water management. Considering the low capacities of local administration in Việt Nam, simplified household data collection is expected to improve rural water supply and sanitation management and planning. The approach of the present study therefore is to examine housing structures for their informational value on household welfare and the state of domestic water supply and sanitation. The outcomes of the study are thought to facilitate an enhanced municipal water management planning on communal level.

The terms “household” and “house” are frequently regarded synonymously, as dwellings usually accommodate households. For anthropologists a household is “the basic residential unit in which economic production, consumption, inheritance, child rearing, and shelter are organized and carried out” [6]. From the economic point of view the household can be seen as a resource system or income-pooling system of people living in the same residence [12, 15, 16, 18]. It was Levi-Strauss [7] who defined the “house” as “a corporate body holding an estate made up of both material and immaterial wealth which perpetuates itself through the transmission of its name, its goods, and its titles down a real or imaginary line”. Scholars, despite criticisms, have continued to employ a “house” centred focus in the study of social organisation. Especially in regions like Southeast Asia cognatic kinship principles are frequent; Levi-Strauss” vision of “house based societies” is recognised as an indigenous referent for a socio-residential unit [3, 10, 11, 17]. More recently the state of housing was revealed as useful indicator of household poverty in Chinese cities [19]. Ya Ping Wang [19] sees a strong connection between household income, housing, and poverty. The same relationship was shown for post-reformation developments of economy, society, and housing in Việt Nam (see [13]).

Housing policies in Việt Nam changed completely after the implementation of Đổi Mới reforms in 1986. Pushed by further economic reforms in 1992 people built new houses or improved their existing houses. Socio-economic changes mixed up with cultural, lifestyle and behavioural changes made the household an especially important economic unit. The improvement of the housing condition has been tightly linked with economic development, occupational orientation, and income generation. Poor households have little or no chances to improve their housing condition. High-income households spend more money on housing conditions than poor dwellers. Households with exclusive use of basic facilities (toilet, kitchen, and bath) tend to have higher incomes [13]. Bennett [1] presents domestic water demand as a function of the way water is transported to the household and the number and kinds of plumbed appliances in the house. Thus a linkage between household welfare, housing and domestic water consumption seems likely.

This article presents the results of a household survey conducted in a handicraft village located in the Nhuệ-Đáy river basin. Taking the above described findings up this study aims to evaluate house types as indicators for household welfare and the state of domestic water supply and sanitation.

II. CLASSIFICATION OF HOUSING UNITS

Information on housing conditions has been gathered in Vietnamese population censuses since 1989. When designing the census in Việt Nam, United Nations (UN) recommendations on population and housing census have been consulted [8]. Accordingly, the General Statistics Office (GSO) of Việt Nam classified 3 house types for the 1989¹ and 4 house types for the 1999 census respectively (Table 1).

Table 1. House types distinguished during 1999 household census in Việt Nam [8].

Type 1 Permanent	Villas, multi-story houses, apartments of multi-storey buildings, multi-floor buildings assembled from pre-fabricated components, brick constructions with flat concrete roofs.
Type 2 Semi-permanent	Houses with walls made of brick/wood/wood frame and with roof made of tile/cement-mortar roofing/metal roofing etc., houses constructed of equivalent materials.
Type 3 House with durable frame and leaf-roof	Houses with frame made of wood (all area of roof is propped up by durable pillars), with roof made of leaf/bamboo/oil-paper and its duration of use is more than 15 years.
Type 4 Simple	Houses of simple composition and primitive materials; walls are not built of bricks or wooden frame; roof of bamboo/leaf/oil-paper etc.

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¹Permanent houses, semi-permanent houses, and simple houses

The housing classification used by the GSO changes frequently and differs between household census and Việt Nam Living Standard Survey (VLSS). During the 2002 survey² 5 house types³ were distinguished. However, for the 2004⁴ and 2006 (GSO, 2007) surveys the GSO reverted to permanent, semi-permanent, and simple houses as applied in the 1989 census. This adjustment process shows that a general housing classification, adapted to Việt Nam and concerned problems, has not yet been found.

Figure 1. Housing units according to UN recommendations [14].

The UN recommendations distinguish between conventional dwellings and other housing units (Fig. 1). A conventional dwelling is intended for habitation by one household. It is a room or suite of rooms in a permanent building. This structure, as distinguished from semi-permanent housing units, is expected to maintain its stability for 15 years or more, depending on the national definition of durability. Conventional dwellings are separated into 2 types taking into account the equipment with piped water, toilet, bath, and kitchen [14].

III. METHODS AND MATERIALS

In spring 2007 a household survey was conducted in Tòng Xá village (Nam Định province). Interviews were held in 320 households. Socio-economic data and information about domestic water supply and sanitation were gained from heads of the particular household. For October 2006 and March 2007 tap water consumption data of supplied households in Tòng Xá was obtained. The data was delivered by the Ý Yên Water Supply Company. For a profound overview about the study area, see Nguyễn Thanh Lan et al. [9].

Subsequent to an initial observation of the housing situation in Tòng Xá, house types were classified on the basis of UN recommendations [14] and the GSO system as presented by Mai Van Cam and Chu Thi Loan [8]. The characterization considered storey number, building materials, location of basic facilities (kitchen, bathroom, toilet), and building design. Accordingly, house types A and B comprise permanent buildings. Type A dwellings are always equipped with all basic facilities whereas this is not obligatory for houses of type B. Type C dwellings are semi-permanent buildings without basic facilities inside the house (Box 1). Simple houses or dwellings solely made of wood and bamboo were not found in Tòng Xá. Information about the house type was gathered for dwellings of all interviewed households. The collected data was processed with SPSS statistical software.

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²Living Standard Survey 2002, GSO, www.gso.gov.vn/default_en.aspx?tabid=483&idmid=4&ItemID=1843, retrieved 10^th August 2009.

³City house, permanent house with private bathroom, toilet, and kitchen, permanent house without private bathroom, toilet, and kitchen, semi-permanent house, and simple or other houses.

⁴Living Standard Survey 2004, GSO, www.gso.gov.vn/default_en.aspx?tabid=483&idmid=4&ItemID=4343, retrieved 10^th August 2009.

Box 1. House types in Tòng Xá based on GSO system und UN recommendations (see: [8, 14]).

House type A Permanent Kitchen, bathroom, toilet always inside the dwelling
House type B Permanent Kitchen, bathroom, toilet partly outside the dwelling
House type C Semi-permanent Kitchen, bathroom, toilet always outside the dwelling

IV. RESULTS AND DISCUSSION

1. Socio-economic situation of households in Tòng Xá village

The study revealed a diversified income structure of households in Tòng Xá. In average each household has 5 members and the mean area covered per household is 269.71 m². However, a cogent relationship between the area of households and the welfare of dwellers was not proved. The income structure of Tòng Xá shows characteristics of a craft and trade village: only 45.5% of inhabitants earn their main income from agriculture (Tab. 1). The mean income of farmers is below poverty line.⁵ There are several households that have additional income sources. Home based handicraft (wood working and food processing) and pig breeding are common sideline bases. Unlike earnings from agriculture, household based craft activities offer a more profitable, permanent and stable income. Thus the planning reliability for

Table 1. Main income source, mean income in 1,000 VND (N = 270) of households (N = 319), and income quintiles in Tòng Xá, 2007.

Income source / Income quintile	%	Mean income per capita/month
Agriculture	45.5	158.36
Salary	28.2	555.77
Craft and trade	23.2	2,461.33
Pension	3.1	631.98
Total	100	871.92
1 “poorest”	20	94.61
2 “near poorest”	20	174.55
3 “medium”	20	253.81
4 “near richest”	20	404.82
5 “richest”	20	3,531.77

expenditures is increased. However, when a domestic business activity generates more income than farming, it is considered the main income source. Most notable craft and trade activities are metal working as foundry and lathing (38% of businesses), service (31%), and wood working (25.4%). Especially metal working ensures a high income and a large number of jobs. Salaries in casting companies as also earnings from private business offer significantly higher income than agriculture. Moreover, medium sized metal working generates well paid jobs in trade services. Nevertheless, social disparities are intensified by industrialisation

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⁵ 200,000 VND per capita and day according to Decision 170/2005/QD-TTg, General Statistics Office (GSO) of Việt Nam, retrieved from:

www.gso.gov.vn/default_en.aspx?tabid=462&idmid=2&ItemID=2948, 18 July 2009.

Processes in the village. For Tòng Xá the difference between income quintile 5 (richest) and income quintile 1 (poorest) is 37.33. For comparison, in 2006 the same ratio for Nam Định province was only 5.42 (GSO, 2007).

2. Housing structures and household welfare

According to the study, in Tòng Xá the majority of residents live in type B and C dwellings, only 13% of interviewed households reside in house type A (Fig. 2). The mean number of residents per house is 5 for each of the dwelling types. Differences in the socio-economic situation of households are reflected by the housing structure. The 3 house types display the spectrum of household welfare in the village (Tab. 2). The strongest differences were found between type A and type C dwellings. The differences in household welfare indicated by house types B and C are considerably weaker (Tab. 3). The mean income of households living in type A dwellings is significantly higher than earnings of households living in house type B or C. Among residents of type A dwellings, tradesman is the most frequent occupation. Farmers are predominant residents of house types B and C. Employees which work mainly for one of the casting companies in the nearby industrial zone account for about 30% of residents in dwellings of each type. Traditional household based economic activities (e.g. pig breeding, wood working) are performed by households living in type B and C dwellings in equal shares. However, these inefficient domestic businesses are irrelevant to residents living in house type A.

Figure 2. Distribution of house types among interviewed households (N=320)
in Tòng Xá, 2007.

Table 2. Descriptive statistics of household welfare for house types in Tòng Xá, 2007.

Dependent variable	Parameter	House type A	House type B	House type C
Main income source	N valid	39	146	134
Agriculture	yes = 1	7.7%	41.1%	61.2%
Salary	yes = 1	33.3%	27.4%	27.6%
Craft and trade	yes = 1	53.8%	29.5%	7.5%
Household business	N valid	40	146	134
Pig breeding	yes = 1	2.5%	41.1%	43.3%
Wood processing	yes = 1	0%	9.6%	11.2%
Metal working	yes = 1	32.5%	9.6%	0%
Household income	N valid	35	131	104
Mean income (1,000 VND/capita/month)	Mean	4,240.04	461.35	255.58
	Stand. Dev.	8,480.33	1,189.0	198.26
	Min	143	22	50
	Max	35,417	12,600	1,100

Table 3. Pair-wise tests of house types on independence and strength of relationship regarding household welfare.

Dependent variable	Sample		Test parameter
Main income source	House type		Pearson χ²	Phi
Agriculture	A	B	15.292**	-0.288**
	A	C	34.598**	-0.447**
	B	C	11.292**	-0.201**
Salary	A	B	0.531	0.054
	A	C	0.481	0.053
	B	C	0.002	-0.002
Craft and trade	A	B	8.095**	0.209**
	A	C	44.187**	0.505**
	B	C	22.016**	0.280**
Household business	House type		Pearson χ²	Phi
Pig breeding	A	B	21.221**	-0.338**
	A	C	22.863**	-0.362**
	B	C	0.137	-0.022
Wood processing	A	B	4.148**	-0.149**
	A	C	4.900**	-0.168**
	B	C	0.194	-0.026
Metal working	A	B	13.282**	0.267**
	A	C	47.066**	0.520**
	B	C	13.526**	0.220**
Household income	House type		Mann-Whitney U	Z
Mean income (1,000 VND/capita/month)	A	B	868.0**	-5.644
	A	C	467.5**	-6.571
	B	C	5,801.0	-1.955

** Significant at 0.05 level

3. Household based water supply and sanitation in Tòng Xá village

Rainwater and well water (dug and drilled) are traditionally used local water sources in Tòng Xá. Since 2001 the village has been connected to a municipal tap water supply. At the time of the survey 62.2% of 320 interviewed households had a municipal tap water connection available. Nevertheless, 70.9% of the interviewed households stated to use centrally supplied tap water. The difference illustrates neighbourly help to households that cannot afford the water connection. Recipients of the tap water fill up their rainwater cisterns and pay an agreed price. This kind of unofficial tap water supply is found in type C (14.2%) and type B dwellings (6.1%). All tap water users living in house type A have a municipal tap water connection available.

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⁶ Outlier adjusted

The mean tap water consumption⁶ is 61.36 l/person/day. In terms of utilised water sources dwellers were distinguished between: 1. Households using municipal tap water only (17.8%); 2. Households using municipal tap water and local water sources (45%); and 3. Households using local water sources only (37.2%). The mean tap water consumption at households which exclusively use tap water (85.73 l/person/day) is significantly higher than at households using municipal tap water and local water sources (52.12 l/person/day).

Main types of toilets in Tòng Xá are waterless pit latrines and flushing toilets. These toilet types are distributed nearly equally. In 55.7% of households (N = 318) residents use a pour flush toilet, 43.4% of households are equipped with a dry toilet. In 6 households both types of toilets are available. In 8 interviewed households (2.5% of N = 318) residents had no toilet. They were using a bucket latrine, the pig hutch or the toilet of the neighbour.

4. Housing structures and domestic water supply and sanitation

In Tòng Xá the state of domestic water supply and sanitation is reflected by the house type. The strongest differences were found between type A and type C dwellings (Tabs. 4 & 5). The supply degree of municipal tap water is highest for households residing in type A housings. In such house types 47.5% of households exclusively use public tap water, whereas only 2.5% are solely dependent to local water sources. The supply degree of municipal tap water is decreased by nearly 20% for type B dwellings and is lowest in house type C. In contrast, the utilisation of local water sources (well water, rainwater) raises from house type A to B and is highest in type C dwellings, in which 54.5% of households use local water sources only.

Table 4. Descriptive statistics of domestic water supply and sanitation for house types in Tòng Xá, 2007.

Dependent variable	Parameter	House type A	House type B	House type C
Water supply / sources	N valid	40	146	134
Own public tap	yes = 1	97.5%	69.2%	44.0%
Rainwater use	yes = 1	45.0%	68.5%	82.1%
Private well	yes = 1	22.5%	74.0%	81.3%
Public tap water use only	yes = 1	47.5%	17.1%	9.7%
Local water sources use only	yes = 1	2.5%	30.8%	54.5%
Water consumption	N valid	27	84	49
Mean tap water consumption (litres/person/day)	Mean	102.44	56.37	47.28
	Stand. Dev.	54.42	42.09	38.12
	Min	0	0	0
	Max	190.86	190.32	153.23
Sanitation	N valid	40	145	133
Pour flush toilet	yes = 1	100%	64.8%	32.3%
Dry toilets	yes = 1	5%	34.5%	64.7%

Important differences between house types A, B, and C in terms of water storage capacity were figured out. Dwellers living in type A houses possess significantly larger storage capacity (9.7 m³) compared to both other house types B (5.5 m³) and C (4.5 m³). Residents living in type C dwellings have substantially lower water storage capacity in comparison to households residing in the other house types.

Table 5. Pair-wise tests of house types on independence and strength of relationship regarding domestic water supply and sanitation.

Dependent variable	Samples		Test parameter
Water supply / sources	House type		Pearson χ²	Phi
Own public tap	A	B	13.530**	0.270**
	A	C	35.801**	0.454**
	B	C	18.044**	0.254**
Rainwater use	A	B	7.472**	-0.200**
	A	C	21.790**	-0.354**
	B	C	6.889**	-0.157**
Private well	A	B	35.649**	-0.438**
	A	C	48.869**	-0.530**
	B	C	2.177	-0.088
Public tap water only	A	B	16.042**	0.294**
	A	C	29.324**	0.411**
	B	C	3.281	0.108
Local water sources only	A	B	13.530**	-0.270**
	A	C	34.050**	-0.442**
	B	C	16.036**	-0.239**
Water consumption	House type		F	t
Mean tap water use (litres/person/day)	A	B	5.751**	4.028**
	A	C	8.488**	4.673**
	B	C	0.589	1.243
Sanitation	House type		Pearson χ²	Phi
Pour flush toilet	A	B	19.424**	0.324**
	A	C	56.418**	0.571**
	B	C	29.309**	0.325**
Dry toilet	A	B	13.486**	-0.270**
	A	C	43.797**	-0.503**
	B	C	25.284**	-0.302**

** significant at 0.05 level

The mean tap water consumption of households living in house type A is significantly higher than in house types B and C. The tap water consumption of households in types B and C dwellings are similar to Vietnamese planning figures for clean water supply in rural areas (60 l/person/day).⁷ However, the water demand of households residing in type A houses is close to consumptions reported for the Vietnamese city Buôn Ma Thuột [2]. The increased demand indicates the substitution of local water sources by centrally supplied tap water. The mean tap water consumption is significantly higher at households having no well water or rainwater available. According to Grothe et al. [4] also the use of flushing toilets causes increased tap water consumption. Although the availability of private wells or rainwater and municipal tap water are dependent to each other, no linkage between flushing toilets and local water sources was found. However, the equipment of households with flushing toilets depends on the availability of a tap water connection.

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⁷GoV (Government of Vietnam) (2006) Sector Programme Support to Water, Sanitation and Hygiene Promotion, DANIDA, June 2006, retrieved from www.danidadevforum.um.dk/NR/rdonlyres/0788AFEF-2A45-48F2-A538-1F16520D2B27/0/WSPS_II.pdf, 10 August 2009

Considerable differences between house types were also revealed for the sanitary equipment of households. All type A dwellings are provided with a pour flush toilet. Remarkably, 5% of households residing in house type A had an additional dry toilet available. In these 2 cases the grandparents refused to use the pour flush toilet inside the house. Only 32.3% of households residing in house type C possess a pour flush toilet, the traditional dry latrine is widespread (64.7%). In house type C (4.5% of N = 133) and in house type B (1.4% of N = 145) households were found to have no toilet available.

V. CONCLUSIONS

The 3 examined house types are capable of indicating different degrees of household welfare in Tòng Xá. The strongest differences were revealed between permanent houses with all basic facilities (type A) and semi-permanent houses (type C). Type A dwellings represent households with a significantly higher welfare compared to households living in house type C. Residents living in permanent houses without all basic facilities (type B) are in a transitional state of living standard and welfare. However, households accommodated in type B dwellings frequently show socio-economic characteristics similar to households which reside in house type C.

The supply degree of municipal tap water, well water, rainwater, as well as the availability of dry and flushing toilets can be indicated by house types. All these parameters influence the tap water consumption. The demand on municipal tap water increases from house type C to B and A. Thus house types are suitable to distinguish the tap water consumption of households. Nevertheless, the tap water demand of households which reside in house types B and C does not differ significantly. House type A represents mean tap water consumption at urban level, whereas type B and C houses comply with planning figures of clean water demand for rural areas in Việt Nam.

As pointed out in the present study, it is reasonable to distinguish between permanent buildings with all basic facilities and permanent buildings without all basic facilities. Such segregation revealed remarkable differences between households living in permanent houses. Also, it emphasised differences between households that live in type A and C houses respectively. Due to the relation between water consumption and the number of piped water supplies inside the building, the provision with piped well water and rainwater supplies to the house is considered a crucial parameter for future studies.

Acknowledgements: The study was conducted in the frame of an IWRM project in Việt Nam financed by the German Federal Ministry of Education and Research (BMBF: 02WM0765). All work in Tòng Xá village was kindly supported by the Peoples Committee of Yên Xá commune and Nam Định Provincial Department of Science and Technology (DoST).

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