Fluoride Action Network

Development through rainwater harvesting

Source: Daily News (Sri Lanka) | Director, Lanka Rain Water Harvesting Forum, President, International Rainwater Catchments System Association
Posted on September 19th, 2009
Location: Ceylon

Sri Lanka’s three decades of conflict leaves the Northern and Eastern Provinces most affected, with infrastructure and institutions non-functional, homesteads in disrepair, livelihoods destroyed and most people unsettled and many traumatized. Now since the war is over and people and the land is free from the clutches of the terrorist, the battle is now on to rebuild infrastructure and houses, resuscitate the institutions, resettle and rehabilitate the affected and displaced people and help them redevelop their livelihoods.

It is only through social and economic development in these areas and people we can hope to bring ethnic harmony, trust and mutual respect among all communities to build a united Sri Lanka.

Any development activity cannot be done without water, which is not only a basic need of living beings, but also important for food production, sustenance of biodiversity, ecology and overall health of the environment.

The pressure in the available of water resource is ever increasing due to the rising population, pollution and climate change variability. Therefore, provision of water will be the greatest challenge for development activities in the North and East.

Water resources are limited in the North, Eastern, North Central and North Western Provinces. Ground water is the only source of water in many of these areas and has also been over exploited. In many areas in the North, North Central and Eastern province and the water contains a high degree of fluoride in ground. Excessive use of agro chemicals and lack of sanitary facilities led to further pollution of ground water and high levels of nitrate and faecal Coliform are the evidence of poor quality ground water.

In recent years, high incidence of chronic kidney disease has been reported from the North Central and Eastern provinces. In Anuradhapura alone over 200 deaths are reported annually. Although the root cause is yet unknown, there is evidence that it is water related. Medical finding on chronic kidney disease is made clear that irrespective of the root causes, patients continue to consume water containing fluoride which is highly harmful. With five to 10 percent of the population being affected in certain areas and mortality rates escalating, preventive measures need to be taken.

Due to the current situation in the North, IDP returnees will resettle in the Eastern, North , North Central and Western Provinces in large numbers.

This will create more pressure on water resources and aggravate water scarcity as well as health problems. Water scarcity in any location leads to high incidence of water related diseases and sanitary problems.

Lack of water in an agri-based rural economy, will adversely affect the socio-economic well-being of the community. Small scale home gardening is one of the prominent economic activities in the North and East. Lack of water supply results in poor maintenance or total negligence of home gardens and it will have a series of net impacts on the economy. Low productivity of land, food insecurity in rural and urban sector, nutritional deficiencies especially among children and women, lack of income, high dependency on external assistance, and poor living standards are a few out comes of water scarce condition.

Potentiality of rainwater harvesting

In a crisis situation like this, the best option is to use the preserved rainwater for domestic and non domestic use.

Proper promotion of rainwater harvesting technology motivate the users to supplement their water sources and thereby reduce the over exploitation of other water resources.

Rainwater harvesting is accepted as a feasible water supply option in many countries and even in Sri Lanka, potentiality in rainwater harvesting is well documented in the National Rainwater Harvesting Policy.

Domestic rainwater (roof water) harvesting technology introduced in other areas with similar climatic condition offer reasonably good services to beneficiaries. Average annual rainfall experienced in the target areas range from 750 mm in Mannar to 900 mm in Anuradhapura district. The rainfall pattern in Sri Lanka is bi-modal and depends on the two monsoon seasons. The driest months of the year range from June- September in Anuradhapura district and May to September in Mannar district ( four to five months).

An average roof area of 50 m2 in Mannar district will provide the households with at least 40 litres of water per day with an 8,000 litre tank during the driest period from July to September. This will serve households with five people the minimum water requirement of the person which is eight litre per day for drinking and cooking. A tank of 8,000 litres will serve households with 40 litres per day for six to seven months.

Run off rainwater from the ground can also be collected and preserved in the home garden for agriculture purposes and to recharge the groundwater table. For example a two-acre land in an area, which receives annual rainfall of 1000mm, has the potential to store minimum 12,900 m3 of water annually through surface run off. A traditional ‘paththa’, a garden pond of 100 m3 volume can be filled very easily in an hour’s intense rain, and the water collected can be used for agriculture purposes effectively by using water conservation irrigation methods such as drip irrigation and pot irrigation, while the excess can be guided to recharge the groundwater table. A project implemented by the Lanka Rainwater Harvesting Forum in Kotavehera D.S of Kurunegala District has shown increased availability of water for drinking and crop production through introduction of rainwater harvesting technologies. It has also brought many other social and economic benefits to households. It has reduce the daily average household time (mostly women’s) spend to fetching water from one hour and 20 minutes to average 12 minutes. Average annual income from home gardening has increased from Rs. 4,000 to Rs. 13,000.

Rainwater harvesting during disasters

The tsunami reported to have contaminated 40,000 wells around the coastline where over 60 percent of the people had relied on groundwater supply. Rainwater harvesting systems built by the Lanka Rainwater Harvesting Forum in the tsunami affected areas in South and East provides 4,000 households with drinking water to their door step. Easy access to water supply system has brought many other benefits to these households such as reducing the time spent on collecting water, more reliable supply, fluoride free, better sanitation practices, more water security and availability of water for home gardening. Cyclone Nargis of May of 2008 which affected 37 townships in Myanmar left 130,000 people missing and 2.4 million were severely affected. To prevent further disaster through lack of safe drinking water the authorities introduced improvised rainwater harvesting system using temporarily shelters, bamboo gutters and easily transportable storing vessels.

Continuous Contour Trenching and other water harvesting technologies applied in a remote village of Hiwar Bazaar in the Maharashra state in India which receives only 80 mm annual rainfall has transformed barren lands to fertile land and has reduced 100 percent poverty in the village to zero in just five years.

Similarly, in Gunzu province in North China which receives on 380 mm of annual rainfall through a Government introduced project called 1-2-1 project, which means each family in the area without availability of surface and groundwater would get subsidy to build one hardened catchment yield ( roof or paved area), two under ground tanks and one piece of land for courtyard economy.

The introduction of rain water harvesting has made possible the farmers to grow one harvest of rice and one harvest of irrigated corn instead of one harvest of rain fed corn before the project.

The yield has increased by three folds and the income by four folds.

Simple rain water harvesting technologies introduced in IDP welfare centres will reduce expenses borne by the Government and other organizations on bowsering water from far, especially during the approaching rainy season.

This will also reduce flooding to some extent. By introducing awareness on rainwater harvesting technologies and water conservation practices as well as good hygiene measures to the communities from an early stage will ensure continuous practice of these technologies when they return to their homes. Introduction of rainwater harvesting technologies to resettled areas will reduce the pressure on available resources.

Practice of rainwater harvesting will bring a sense of responsibility to conserve water in one’s own land, village and region as well as bring about a new dimension of solidarity and tolerance between people and communities in watersheds, between boundaries.