His Majesty King Bhumibol, in his ceaseless efforts to improve the living standards of the rural people, has developed a new theory on land and water management. It is based on the division of the agricultural land of each rural household, which averages 10 to 15 rai (=1.6 ha to 2.4 ha), into four parts according to use in the proportion of 30-30-30-10 as follows:

Part 1: 30 per cent of 10-rai piece of land (about 3 rai or 0.48 ha) is used for a reservoir. This should be dug to a depth of four metres for a capacity of 19,000 cubic metres of water collected from rainfall, which will be enough to irrigate the crops throughout the year. On his many visits to his people in the rural areas, the King has always stressed the importance of water to agriculture, especially to the rice crop which thrives on water. Since building large reservoirs is becoming more and more difficult due to the expanding population and the decrease in the amount of land available. The King advocates the building of household reservoirs. These, apart from providing water for the crops, can also be used to raise fish and aquatic plants, thus adding to the household income.

Part 2: 30 per cent of the land (about 3 rai or 0.48 ha) is devoted to rice cultivation which will produce enough rice for the household needs.

Part 3: Another 30 per cent of the land ( 3 rai or 0.48 ha) may be used for growing more rice or horticultural crops, depending on the local conditions and the market demand.

Part 4: The remaining 10 per cent of land (1 rai or 0.16 ha) is used for building a house, paths and ditches and also for growing household vegetables and raising livestock.

The implementation of the New Theory will help farmers achieve self-sufficiency at a frugal level.

His Majesty has made further comments about water supply. First, whereas the household reservoir has a capacity of 19,000 cubic metres, a total water reserve of 10,000 cubic metres is enough to follow the cropping regime throughout the year. Second, the evaporation of the water in the four-metre-deep reservoir is one centimetre per day without rainfall. Thus, if there is no rain for 300 days in a year, which is unlikely in Thailand, there will still be one metre of water left in the pond. Third, since there are numerous large reservoirs distributed throughout the country, they will serve as a back-up system for the small reservoirs, enabling the New Theory to work effectively.

In order to prove the feasibility of his New Theory, the King arranged to make a case-study at Wat Mongkhon Chaipattana, Chaloem Phrakiat County, Saraburi Province. The experiment proved highly successful and farmers in various parts of the country have adopted the methods and put them into practice.