Asses the safety Level of the Water from the Sand Dam


1.1               Background

Yatta is in Kitui County in the former Eastern province. It is among the areas which receive much rainfall in the country due to their high altitudes. However, climatic changes resulting in reduced rainfall, increase in temperature and reccurrent draught in the area have been experienced. This change has resulted in negative impact on the socioeconomic development among the rural dwellers since rainfall is the major souce of water (Quinn yet al., 2018). Consequently, creation of dams has been the main form of water conservation technique for home-use and agriculture. Dam creation dependent on the local experience in water harvesting, sieving, storage, and release has largely been adopted (Quinn yet al., 2018).

Food shortages and chronic lack of adequate quality water are a major global concern with higher impact being felt in arid and semi arid lands (ASALS) which accounts for about 89% of the Kenyan dry land (Njoka et al., 2016). Consequently, residents are always experiencing periodic water shortages for domestic and agricultural practices. Therefore, water harvesting methods have not been optional. Sand dams, ponds, roof water harvesting and earth dams has been on the increase in such areas (Kimani et al., 2015). Among the water harvesting methods adopted, sand dams have been the most common due to their reliability in being cheap on contruction, their capacity to prevent a lot of water evaporation, and prevention of contamination from water borne diseases (Petersen and de Trincheria, 2015). This is made possible by the slow sand filtration process through the sand layers that would have accumulated over time along the banks of the dam making it safe for domestic use. However, since the sand dams are open, they are prone to chemical, physical and microbial contamination especially during the heavy run off. Water safety from the sand dams have increasingly been of great concern especially due to its possibility to affect health of the ASAL dwellers. The microbial load is liley to cause water borne diseases. Additionally, the chemical pollutants are likely to cause short or long term effect while the physical contaminants may make the water to be unaceptable. Water contamination from fecal matter among others have been a potential risk to illnesses causing diarrhoea, fever or death especially when the water is used at a household level. Unfortunately, little study has been done on the safety of water from the sand dam (Quinn et al., 2018).

Boiling of  water is the  most common method os water purification at household level. However, water is prone to recontamination in addition to it being expensive (WHO, 2008).  According to WHO (2002), 38% of Kenyan consume contaminated water.  Poor water supplies, sanitation, and hygiene pose a major threat to the health of children under the age of five. Diarrhoea is of great concern among children since it has the potential for lifelong effects like limitation to physical and cognitive development (UNICEF, 2010).

Therefore this research project will focus on identifying some of the major pathogenic micro- organisms that are found in dam water in Yatta constituency. It will also evaluate the risk factors associated with dam water and how they can be dealt with in addition to identifying the water treatment practicess at household level.

1.2              Statement of the problem

Water scarcity has become a major concern worldwide due to unpredictable weather changes as a result of global warming. The experience of residents at yatta has not been exceptional either. In addition to Yatta being a semi-arid area it has only one permanent river. Therefore, People have been in the past forced to go for miles in search of water for domestic purposes from borehole water-points or from the Permannet River. Resultantly, over the years, more people are opting for creation of sand dam in their localities to collect effluent water during the rainy season. Unfortunatly, the run off water carries with it the microbial, physical and chemical contaminants. More so, the sand layers built overtime are dependent upon to filter water of which, it may not be very effective exposing the consumers to waterborne illnesses. Additionally, the sand dam is uncovered increasing the possibility of contamination from the environment.

Water safety in the sand dams may be highly compromised. Heavy down pour decreases the effectiveness of the sand layers in filtration allowing more contaminants to pass through with the filtrate. Microbial contaminant are of great concern because of their pathogenic nature with potential of being fatal. Additionally, water from the sand dams is used directly as it is at the household level without any treatment. This creates a great potential for waterborne illnesses which can be fatal.  Hence, there is need to asses the safety level of the water from the sand dam.

1.3              Justification

Aproximately,  1.7 million people are reported to die annually from water borne diseases globally especially children under five. Children from developing countries are the most affected. Lack of proper understanding and attitude towards water safety are the leading contributors to not treating water hence exposing the households to waterborne disease. This study includes the study on the knowledge, attitudes and practices at the household levels which will inform on the exposure level to pathogens and correllation of food borne incidences, a gap which is yet to be clossed (Kioko & Obiri, 2012). Hence, the findings will be essential in formulation of safe water policy in addition to educating the residents on effective water treatment methods.

Diarrhea, fever, stomach ache and urinary infections are a common occurence where food safety and hygiene is not oberved. This has not been exceptional with Yatta residents.  E.coli, staphylococcus aureus, salmonella and B. Cereus which are the targetted poathogens in the study?


1.4       Sand Dam as a Source of Water

Sand dams are water harvesting techniques that involves construction of small dams across streambeds in ASALS that experience irregular high rainfal. The water run off carrys with it the topsoil and surface runoff.  While the sand settles behind the dam wall, lighter particles are carried over the dam’s spillway. Cummulatively, the sand behind the dam levels in height wth the spillway signifying its maturity. Maturation may take over 7 years but it is highly dependent on erosion (Eisma & Merwade, 2020).  Depending on the use, the water is abstracted by the locals by scoop holes, infiltration to a tank behind the dam or the water is piped to a tap or infiltration gallery of  sealed shallow well with a hand pump (Ndunge et al., 2019).

Because of their decrease in  evaporation and potential to preserve water, the residents living near the sand dams have more advantage in having access to water for a alonger period. Consequently, the water has been used not only at household level but also in micro irrigation increasing the economic strength of the locals (Maddrell and Bown,2017). Additionally, the close proximity to the source of water reduces the time spent in search of water allowing them more time in focusing in hygiene and food preparation hence, improving on their health in comparison to their countreparts who have to walk for long distances in search of water. The close proximity has also allowed parents to relieve their children off the duty of having to fetch water hence, allowing them to focus in school (Ritchie, et al 2021).

Sand dams have been largely been recommended among the ASAL due to their ability to raise the water table, prevent water evaporation and ability to harvest sand for construction. They are  largely found in Kenya especially in the East (Ndunge et al., 2019).However, the water source has not been with limitations. The water collection methods and their accessibility by both human and animals, has exposed the water to pollution.  Coliforms is a normal occurence signifiying fecal contamination in the water. Additionally, the mode of water harvesting method has impact on the turbidity of the water. Traditional water harvesting method using scoops results in more turbid water than using shallow wells. Therefore, residents are encouraged to use more efficient abstraction method or encouraging vegetation cover on the dam (Ndunge et al., 2019).

1.5              Hygiene Altitude,Knowledge and Practices at Household Level

Clear and odourless water is mostly assumed to be clean with majority of the users hardly treating it before use. Clorination, filtration and sedimanetation are the most common water treatment methods. Boiling of water which is vital is hardly practised especially when the water is assumed to be clean.The treatment method varies differently depending on the water sources with chlorination being the most prefered (Kioko and Obiri, 2012).  River water is largely assumed to be dirty hence boiling and chlorination are the most opted water treatment methods.  Kioko and Obiri, (2012) found 60% of the residents of Kakamega to have a general assumption of their water being safe with water from the river scoring the lowest score on the perception of being safe. This definitely showed a lot of ignorance on the possible sources of contamination along the water ways. Additionally, on water treatment.

Similar findings were found by Graber Neufeld, et al., (2020). whereby 75% of the respondnents who used sand dam water believed the water to be clean for drinking due to its physical appearance (50%), convinced that the sand filtered it (22%) or there was no reported cases of illnesses from drinking the water 18%).  Consequently, majority did not treat the water. Hence, exposing themselves to possibility of falling ill.

1.6           Prevelance Rate of Water and Food Borne Diseases from Sand dam water

 Water is the most indispensable natural resource yet limited on quality and quantity in most countries. Globally, >1 billion people do not have enough supply of water. Consequently, water borne diseases like dysentry, cholera, diarrhoea, and typhoid fever are a common epidemic since most water sources is communal (WHO, 2010).

Sand dams are most common in ASALs. They are characterised by capturing water run off during heavy downpour. Their capacity is highly dependent on water run off pattern, their size, the design of their wall, ways of abstracting the water and size of the river bed. The fact that the dams are uncovered, unprotected and made of porpous material increases the possibility of contamination from animal waster, processing waste, mining waste and human waste among others. Consequently, people’s health is compromised by suffering from acute microbial contamination or lomg term health effect from chemical contamination (Eisma & Merwade, 2020).

Moïse at al., (2019) found 13% and 52% of water samples taken from shallow wells and scoop holes to be contaminated with E.coli respectively. The high contamination was explainable by the observed animal grazing at the river banks which feeds the sand dams and also along the walls of the sand dams defacating the area hence, E.coli was found in the water. Similary, S.aureus, B.cereus ans salmonella are a common threat compounded by poor knowldege and attitude towards water treatment (Kioko and Obiri, 2012).

1.7         Water Treatment Methods of Sand Dam Water

Globally, majority of people rely on unsafe water sources exposing them to water bornes diseases which soemetimes result in deaths especially among the under five.  Majority of the world population depending on unsafe water are in the sub-Saharan Africa (WHO/UNICEF JMP, 2015).

There is unending need for safe and quality water globally, unfortunatly this is not visible for majority of people especially among the developing countries. The slum dwellers and those living in the rurals are the most affected. This pushes majority of them to outsource water from vendors who may outsource the water from fornal or informal sources. The latter is mostly not treated exposing the consumers to communicable illnesses (Mumbi et al., 2018). This necessitate the need for affordable and reliable water treatments methods at household levels.

Fortunately, household water treatment and storage methods have been found to efefctively destroy pathogens making the water safe for drinking. Some of the commonly used methods include, chlorination, Solar disinfection, filtration, and boiling.  Clorination is the most common followed by boiling. Thereafter, most water is stored in open containers with lids followed by use of narow neck containers with lids (Mkwate at al., 2017). Although the methods have been proven to be effective at laboratory level, their efefctiveness is dependent on the user, level of hygiene and sanitation observed and their ease of use. Unfortunately, people in the rural areas are the least informed on the same, hence the effectiveness is not always guaranteed.

Knowledge on the application of water treatment is an important factor in influencing the effectiveness of water treatment. For instance, Amoukpo  et al., (2018) found 65.3% of the population to be aware of the water treatment protocols to be followed among Alum, lemon oil, Aquatabs tablets, cresol, boiling and palm branch among others. Majority of the residents were found to be confused on the right protocols to be followed especially where sedimentation, filtration and destruction of pathogens is involved. Akowanou et al, (2016) found only a few households treated water even if the water source was not improved howverm majority of them do not follow the protocol.

1.8       Microbial Risk Factors and Microbial Associated with Sand Dam Water

Animal herd are allowed to graze and acess the water from the sand dams. Mostly, there are no fences around the sand dams. Occasionally , the animals would daficate on the surface of the sand dams. It is pressumed that the water would filtrate through teh soil layers, however the filtration is  not always sufficient. Therefore, fecal coliforms would be found in the harvested water (Quinn et al., 2018). Additionally, the sand dams harvest the water run off during the heavy rains. Fecal contamination among other dirt are carried off into the sand dams increasing possibility of fecal coliforms among other contaminaants. Hence, the focus on E. coli for this study.

The mode of harvesting method is a risk factor to water contamination. Traditional scooping method increases possibility of water contamination from the water spillage back to the scooping hole in addition to hand handling and exposure to animals (Graber Neufeld, et al., 2020). These findings were consistent with Quinn et al., (2018) findings of more contamination in water abstracted through scoop holes and hardly any contamination from covered wells. This increases possibility of s. aureus in the water which is one of the bacteria of focus in this study.

B.Cereas is predominanty found in soil and sand which are the main bulding materiala of the sand dams. B. Cereas has also been found in rain water presumed to have been contaminated by durst from the air. Additionally, B.cereas has also been found in ground water through leaching through the soil particles with more contamination being found during the wet season (van der Poel). Their pathogenecity and resistance to heat treatment makes them of great interest in this study.

Hruby et al., (2018) found salmonella to survev in the soil an year after the application of poultry manure. Similary, the pathogen is likely to be found in the sand dam water as effluent water is carried down the drain in the rainy season. Hence, Salmonella is of interest in this research.


1.9       Expected Output

  1. Identification of targetted pathogens from the sand dam water
  2. Identification of hygiene level observed at the household level
  3. Publication of the research findings
  4. Award of MSc. degree award


Appendix 1: BUDGET

  ItemUnit CostTotal Cost
Specisif Objective 1: To determine the prevalence of water and food borne diseases in Yatta constituency          Specific Objective 2 To determine water handling and treatment practices in Yatta constituency          & Specific Objective 3 To determine microbial risk factors associated with dam water in  Yatta constituency  Questionnaire to respondents                   Enumerators (two for two days) SUB TOTALRealm of printing paper Printing cost Transport to and from the field   Training Wages    500 50 500     1000 2500500 3000 1000     2000 10,000 16,500
Specific Objective 4 To determine microbial hazards in the dam water in Yatta constituency  Sample Collection       Sub Total1-litre Cans Carrier Bags50 1000150 1000 1150
Media Purchase                     Sub TotalMacConkey agar EMBA agar XLD agar   TSI agar Urea agar Mannittol agar Plate Count Agar Mannitol-egg Yolk-polymyxin agar      10,000 10,000 10,000   10,000 20,000 10,000 10,000   10,00010,000 10,000 10,000   10,000 20,000 10,000 10,000   10,000   90,000
                   Other Consumables purchase           Sub TotalDistilled Water Saline Water 3% hydrogen peroxide Mark pens Petri Dishes Laboratory log book  1000 500 500   500 10,000 1000  1000 500 500   500 10,000 1000 13,500
Transport Labour (2lab Technicians) Sub Total   10,0005000 20,000 25,000
    Genral Expenses    
Supervision Printing& Binding of Proposal Printing and Binding of Dissertation Publication Miscellenous Sub Total 25,000 1000 100050,000 10000 5000   20,000 20,000 105,000
TOTAL   251,150  

Leave a Reply