Regional Environmental Technical Assistance 5771
Poverty Reduction & Environmental Management in Remote Greater
Mekong Subregion Watersheds Project (Phase I)

RRA Report on

MAE GOK WATERSHED IN CHIANG MAI AND CHIANG RAI PROVINCES

Watershed Profile

By

Mr Colin McQuistan

1.0 Introduction: The Mae Gok Watershed.

The introductory data focuses upon secondary sources collected from provincial departments of various government agencies. This provides an introduction to the present situation in the watershed area as a whole.

1.1 Project area and target of study

The Mae Gok watershed is located in southeastern Myanmar and northern Thailand and covers a total area of 10,870 km². The river Mae Gok originates in Myanmar and covers an area of approximately 2,980 km² in Shan State of Myanmar. The River Mae Gok enters Thailand at the village of Ban Tha Don, in Mae Ai district of Chiang Mai province. The watershed in Thailand covers an area of approximately 7,990 km².

In Thailand, the Mae Gok watershed covers 8 separate districts and 2 minor districts of Chiang Mai and Chiang Rai provinces. This area encompasses a total of 63 sub-districts with 677 villages as registered by the Department of Local Administration (DOLA) of the Interior Ministry. The watershed in Thailand constitutes the Mae Gok river and three principle tributaries, these are the Fang river, Lao river and Suai river. The basic physical attributes of the entire watershed are as follows;

The basal stream flow as measured at the 25 principle water monitoring stations on the Mae Gok river indicate an average flow of 5,280 Million m³ /year. Of this total, an average of 330 Million m³/year is diverted or stored within the watershed. This results in the average stream flow of 4,950 Million m³/year entering the Mekong River.

Table 1.1: The stream flow of the three major tributaries

In 1992 there were almost 240 separate water development projects of various Thai government agencies in the Mae Gok watershed. These ranged in size from farm ponds to village weirs and small scale dams. These projects have a combined irrigation benefit to almost 90,370 hectares. The majority of these projects belong to either the Department of Local Administration or the Royal Irrigation Department.

At present there are 3 water power electricity projects under construction in the Mae Gok watershed. Two of these projects are from the Department of Energy Development and Promotion and the third from the Provincial Electricity Generating Authority. These hydropower projects have a combined power production of 8,675 kilowatts or approximately 29.4 million units.

The water from the Mae Gok watershed is utilised for numerous purposes. The majority demand is for agricultural irrigation, which accounts for almost 96%, with only 4% used for consumption, tourism, and industry. This water demand is predicted to increase but the overall proportion in each activity remains the same.

A study of reservoir simulation utilising the HEC-3 model to predict water supply and demand indicates that overall the water supply situation for the Mae Gok watershed is adequate up to the year 2006, if no major changes in the hydrologic system occur. Although the model predicts shortages in some areas for agriculture especially in the Mae Sao and Mae Lao project areas and for potable water in the Chai Prakan and Fang district. Although the model predicts shortages in the short term they do not appear serious whereas the long term predictions suggest serious problems if the supply and demand situation does not change.

The current physical situation in the Mae Gok watershed suggests the following priority projects for the sustainable development of this watershed.

• Long-term developed plan (before 2006).

• High potential developed plan.

1.2 Land utilisation

Chiang Mai and Chiang Mai are the two most northerly provinces in Thailand both with their northern borders joining Myanmar. Both provinces have a long history of human occupation with Chinag Mai once being the centre of the Lanna kingdom. Both provinces have a wealth of natural resources with large areas of natural forest, agricultural lowland and upland areas inhabited with ethnic hilltribes. This mosaic of land use types, developed to a great extent by the various resident population results in a very diverse landscape. Table 1.2 indicates the land utilisation for the two provinces in terms of agricultural land, Forest land and land used for other purposes.

Table 1.2: Land utilization in Chiang Rai and Chiang Mai : 1985-1993

1.3 Public health facilities

Chiang Mai is a center of high education for northern Thailand with excellent further and higher education facilities. This situation results in the proportion of medical and public health staff to the resident population being higher than in neighbouring provinces. Although this situation occurs in the provincial centres, in the remote districts such as in the Mae Gok watershed the medical provision is poor. Thus if figures for the province as a whole are examined the supply of medical facilities appears adequate.

Table 1.3: The provision of medical staff Chiang Mai and Chiang Rai provinces

If medical staff in the remote districts are examined it is found that the staff supplies reported above are focussed upon the district centres. Thus the provision of medical staff in the Mae Gok watershed itself is poor.

The provision of public health service facilities ranging from large hospitals to small clinics in the two provinces is indicated in table 1.4. As with medical staff these facilities are focussed upon the district centres. The supply of medical facilities to rural areas is often very poor with a total absence of medical facilities for the people living in the mountain regions.

Table 1.4: Medical facilities in Chiang Mai and Chiang Rai provinces

1.4 Social and economic situation

In 1998 the average income for the entire population of the northern region of Thailand was $621 per year. The population of Chiang Mai province reported the highest income for the region with an average of $798. By comparison the average income for Chiang Rai province was $557 which is significantly lower than the average income for the northern region. These figures compare to the national average income of $1,053 per year.

A survey of single household employment in the Mae Gok watershed in 1992 by Chiang Mai university found that single household employment figures are highly contradictory when compared between the two provinces. For example the data for Chiang Rai province ranks occupations in the following order; Farming, Service sector, Arable crops, and Trade followed by a minority in other groups. Whereas, for Chiang Mai province the Service sector is number one followed by other agriculture with rice farming ranked only as number four. This discrepancy is caused by numerous factors, but fundamental to this is the excessively small sample size. Single occupation households constitute only 5% of the registered population and even less when the unregistered hilltribes population is included. Even though this data is highly questionable one important point is indicated. The figures for the service sector in the two provinces are comparable. Thus service sector individuals receive adequate returns and perhaps have insufficient time to undertake additional occupations.

Table 1.5: The number of single occupation households for
specific activities in the Mae Gok watershed

The situation regarding land tenure in the Mae Gok watershed indicates that approximately 50% of the land area is converted to permanent agriculture. A total area of 876,011 Rai is covered by forest of which 855,941% is National Forest Reserve (See section 1.4, page 8). Land is also set aside as community forest land with a total area of 55,221 Rai designated. Of this community forest area only 10,035 Rai has been replanted or 18.2%. For the distribution of land use types see table 1.6.

Table 1.6: Land Tenure status

The second largest land category in the Mae Gok watershed which covers 45.9% of the area or 855,941 Rai is national reserved forest. This large proportion of land, most of which is situated over 500m, above mean sea level is regarded as forest area and is managed by the Royal Forest Department as conservation areas, protected either as national parks, wildlife sanctuaries or class A, protected watersheds.

Table 1.7: Arable agricultural statistics for the Mae Gok watershed

Table 1.8: Livestock raising in the Mae Gok watershed

The distribution of the 1,843,576 Rai of agricultural land which has land documents, in terms of farm size is as follows.

Table 1.9: Farm size distribution

Most industry in the Mae Gok watershed concerns small scale primary agricultural processing. For example rice milling and tobacco drying are the two principle industries. Subsidiary industries present especially located around urban areas include, tea processing and food canning. The majority of these industries are located in Fang district, Chiang Mai province and in the urban area of Chiang Rai.

The principle water sources in the Mae Gok watershed are ponds, streams, rivers, small reservoirs, water-well, and bore holes. The principle river of the Mae Gok watershed is the Mae Gok which flows for approximately 147 kilometers from the Myanmar border in the west to the Mekong river in the east. Flowing into the Mae Gok are three principle tributaries the Fang, Lao, and Suai rivers.

Table 1.10: Dendrology of the tributaries of the Mae Gok river

Data collected in 1992¹ indicated that on average each village registered by the Department of Local Administration (DOLA) in the Mae Gok watershed has 1 community bore hole, 13 private bore holes, 2 community water-wells, and 104 private water-wells.

Table 1.11: Water supply in the Mae Gok watershed

In the Mae Gok watershed there is a problem with drinking water supply. About 45% of households do not have adequate year round supply of clean water as the figures in table 1.12 indicate. In total approximately 53,735 household suffer from a drinking water shortage during the dry season. Traditionally villagers collect rainfall during the rainy season and this is stored for drinking purposes in the dry season. If in previous times this rainwater supply was adequate, then either the amount of rainfall has reduced, the consumptive demand has increased or alternative "stop gap" supplies have disappeared?

Table 1.12: Potable water supply in the Mae Gok watershed

Due to the high agricultural prices that can be achieved for production of crops in the dry season many farmers in the Mae Gok watershed attempt to cultivate crops during this period. To be able to produce crops during this time the farmer must have an alternative source of water, this supply source ranges from wells, bore holes to ponds and other Rainwater storage devices. At present, for off season production 76% of the irrigation supply comes from shallow source wells for example surface ponds or shallow wells a smaller majority utlise deep water bore holes while others rely upon infrequent and unpredictable Rainfall. In most years, this alternative supply is inadequate for the majority of farmers in the Mae Gok watershed.

Table 1.13: Irrigation supplies in the Mae Gok watershed

This shortage results in inefficient land use. In 1992, 394 villages or 58% of all villages in the Mae Gok watershed reported problems concerning insufficient irrigation for agriculture. The farmers from each village are asked to classify their village in terms of; insufficient, adequate or plentiful concerning dry season water supply. This classification is undertaken for a variety of crops from high water demand agriculture such as a second rice crop, through short-term crops, long-term crops, vegetables to fruit which are lower water demanding crop systems. It is found that the majority of villagers suffer water shortage as indicated in table 1.14.

Table 1.14: Water supply sources in the Mae Gok watershed

When the problems related to water use are translated into land use efficiency then the following trends emerge. Villages reporting severe water shortage totals 289 villages, thus 43% indicate serious land inefficiency. An additional 313 villages or 47% indicate a moderate problem. Only 69 villages report adequate water supply, enabling high capacity land use. This suggests that only 10% of the land in the Mae Gok watershed is being used efficiently.

Table 1.15: Number of villages that report a water problem in the Mae Gok watershed

The Mae Gok watershed’s principle factor resulting in poor land use efficiency is the lack of irrigation supply during the dry season. A total of 60.4% of farmers reported that insufficient irrigation supply was their principle agricultural problem. Additional problems faced by farmers in the watershed include financial restrictions and associated problems. Interestingly a lot of the farmers in the watershed are contract farmers. They borrow money in advance to produce a specific crop, such as Tobacco or vegetables. The farmer enters into a contract to produce a specific amount, at a certain quality. But often the farmers find that due to poor rainfall or other problems the contract crop is of poor quality and they cannot thus pay off their debt. This debt is then calculated at very high rates with the farmer becoming tied to a particular company and their crop in a recurring debt cycle.

Interestingly, traditional agricultural problems such as land infertility, flooding, knowledge and labour shortages are not reported in this watershed (see table 1.16).

Table 1.16: Specific agricultural problems reported in the Mae Gok Watershed