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Study objectives
The Kok River Basin study (1998-2000) had two objectives. One was to produce
a framework for integrated planning and management of water resources and the
environment of the Kok River Basin. Another was to serve as a pilot study , from
which experience can be drawn to similar integrated management studies and
practices elsewhere in the Mekong Basin.
Management basis
The development of Kok River Basin is exposed to several external driving
forces. These are determinants, or causes in cause-effect relationships, which
affect the Basin and its water resources, and thereby, directly or indirectly,
the course of its development. Examples are population pressure; pressure from
global and regional competition; increased demand of public services (like
education and health care), and the associated need of funding; and increased
energy prices.
Between them, these forces seem to point at three needs: (i) A need of change (or to adapt to changes); (ii) a need of higher product value per unit of water; and (iii) a need of sustainability.
Apart from the external forces, the development is determined by the demand and availability of raw water, various issues related to specific sectors, and environmental and social consequences of development. Some of the aspects can be controlled by management, while others cannot. Many of the opportunities and constraints will change with time. In other cases, our knowledge about them and the understanding of their significance will change with time.
Integrated management
Integrated management of water resources and the environment is directed
towards the many inter-sectoral dependencies that may be less visible in each
sector plan. Integrated management is well suited for steering the development
clear of constraints, and, at best, to provide an added value to the sector
plans by identifying options and opportunities that may have been overlooked
because they relate to a combination of sectors rather than a single one.
Conceptually, the management can be regarded as three parallel processes, which are closely related and equally important: (i) Goal formulation; (ii) implementation; and (iii) knowledge-building.
Development objective
Management should build on a formulation and occasional re-formulation of clear,
agreed, long-term development objectives. The formulation of such objectives
is a process in itself. While they may be easy to draft in general terms, it may
be time-consuming and intricate to achieve some practical extent of consensus
about them among the stakeholders.
Once agreed on, the objectives can serve as the starting point for policy formulation and implementation. In this connection, the objectives can also serve as a reference for delegation of responsibility from the decision-makers to the specialists.
The following double development objective has been suggested for management of water resources and the environment of Kok River Basin:
An allocation of water resources that is physically feasible, socio-economically suitable, and environmentally sustainable; and
an environmental state of the Kok River Basin complying with standards that have been agreed between the stakeholders.
Natural resources and ecosystems
The Kok River Basin is characterised by stressed ecosystems, distorted water
yields caused by deforestation, soil erosion, landslides and downstream
sedimentation, and, in turn, reduced soil fertility caused by soil erosion and
leaching of nutrients. Visible effects are lack of water in the dry season,
lowering of the groundwater table, and increased floods in the rainy season.
The major part of the project area is influenced by human activities. This is obviously the case for the agricultural farmlands, but even the upland forest areas largely appear as disturbed, encroached, partly cultivated, or recently re-planted. The forests have been under strong pressure for many decades, being felled for timber and for expansion of agricultural land. Today, the status of remaining forests is at 'caution level'
Public water supply
There are two large waterworks in the Basin, operated by PWA: Chiang Rai and
Fang. Another PWA plant is under construction in Chai Prakarn. Elsewhere, the
domestic demand is served by small-scale facilities or individual withdrawals,
based on either surface water or groundwater. The total present demand for
domestic supplies (in the entire Basin) is around 2 m3/s. The corresponding
return flows are estimated at 80 percent.
Groundwater
While
the surface water resources are fully utilised, the groundwater resources (if
they exist) are almost undeveloped. This offer a particular opportunity for
regulation of groundwater abstraction. Well yields are generally characterised
as 'high', and no shortages have been reported. There is no information
available about the size and distribution of the groundwater resources.
Groundwater management must involve effective prevention of contamination. This comprises (1) good practices for use of pesticides and fertilisers, including a ban on the most severe contaminants; (2) retention of all toxic compounds at the point of origin; and (3) disposal of solid waste by means that prevent contamination by infiltration.
Irrigation
Today and in the future, the agricultural sector is by far the largest water
consumer in the basin. Existing irrigation schemes cover a total area of 675,460
rai (1081 km2). The schemes are either diversion schemes or pump irrigation
schemes. All are based on surface water.
There are eight planned reservoirs in the Fang, Upper Lao and Suai sub-basins. They represent an expansion by 30 percent of the area that is irrigable today. The effective impact is larger, because the scarcity of water implies that not all the present irrigation project areas can actually be irrigated, particularly in the dry season (but in some cases not even in the rainy season). It is expected that the actually irrigated areas will increase by 55 percent and 33 percent in the dry and the wet season, respectively.
There is a need of rehabilitation or upgrading of some of the existing schemes, in order to improve their water efficiency. There is also scope for non-structural development measures, like improvement of irrigation management and field application efficiencies. It is evaluated that such measures can improve the water efficiency from 30 percent today to 40 percent in the future. This makes it possible to increase the irrigable area by 10 and 7 percent in the wet and the dry season, respectively. This improvement can be achieved at little or no environmental cost.
Hydropower
There are three mini-hydropower plants in the project area. All are located
in the Fang sub-basin.
Two hydropower schemes are planned: (1) Nam Kok hydropower project (in Myanmar) (storage volume 3,033 Mm3); and (2) Upper Fang multi-purpose project. If the Nam Kok project is implemented, it will cause a general, positive change in the water availability in the Upper and Lower Kok sub-basins. There is scope for an additional (although moderate) development of hydropower in connection with some of the planned irrigation reservoirs. If energy prices will escalate over the next decades, there will be a strong motivation to implement schemes that are feasible or nearly feasible with today's cost-benefit ratio.
Forestry
Since 1989, there has been no commercial forestry in the project area, in
spite of forests covering 47 percent of its area. This is because the forest
areas are now in a state of restoration, following over-exploitation in the
past. The restoration process is supported by a general ban on logging.
In the long term, there is a clear scope for commercial forestry. Once restored, and with proper management, a part of the forest area will become an important commercial asset.
Separate goals must be pursued for upland agro-forestry cultivation. The mountainous forest ecosystems are fragile and under pressure. Agro-forestry is an option for sustaining the upland and mountainous ecosystems, while, at the same time, stabilising the living conditions of the farmers. Management options comprise (i) stabilisation of sloping areas; (ii) maintenance and improvement of the soil fertility; and (iii) improvement of the microclimate. In the medium term, in order to prevent stagnation and marginalisation, additional sources of income must be sought as a supplement to subsistence cultivation.
Wetlands
The two major wetlands in the project area are Nong Luang and Nong Wiang.
Both are partly regulated by structures, and are fairly influenced by human
settling and utilisation. Their ecosystems and biodiversity are not well known.
Both areas are used as water sources and for fishing. Some informal restrictions
on fishing and hunting have been self-imposed by the local communities.
Fisheries
More than a hundred fish species are reported in the project area, including
several economic species. Some species migrate between the Mekong and the Kok
River Basin, where they breed. The yield is relatively low. The standing stock
is estimated at 3-4 kg/rai, which is well below the national average of 15
kg/rai. Fishing is mainly practised for own consumption.
Development of capture fisheries must aim at (1) preservation of biodiversity and habitats (including water quality, important migration routes and breeding grounds), and (2) prevention of over-exploitation. The potential for commercial development is small, but the possibility exists of increasing the yield from capture fisheries in (present and future) reservoirs. A particular concern is the risk of contamination of edible fish by pesticides.
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Tourism
The tourism sector appears as an attractive option for economic development
in the medium term, and, in case of prudent management, in the long term as
well. The development should aim at higher earnings per day spent by
tourists, minimising the environmental impact, and maximising the socio-economic
benefits.
Surface water quality
The water quality and the aquatic ecosystems are exposed to the combined
effects of two threats: (i) The risk of a reduced streamflow in the dry season,
caused by the increased demand of water; and (ii) the risk of an increased
pollution load, caused by population growth, changed lifestyles, intensified
tourism, and intensified agricultural and industrial production.
Today,
there are no sewered areas at all in the basin, and no treatment plants have
been established. Sewage stabilisation ponds are under construction to serve
Chiang Rai Town.
Industries are typically processing plants for fruits and vegetables, or noodle factories. They produce mainly organic sewage. Most industries are located around Chiang Rai, and in the Fang and Upper Lao sub-basins.
No information is available about loadings other than BOD, nutrients and bacteria. It is not known whether heavy metals, chlorinated hydrocarbons and other serious pollutants are released to the environment within the project area.
Loadings from agriculture are influenced by (i) a prudent use of pesticides (including types of pesticides, and application practices); and (ii) appropriate land use management, aiming at protection of headwaters, and prevention of widespread soil erosion. Loadings from industries and hospitals (other than BOD and nutrients) should be controlled at the source.
The rivers do not seem to be exposed much beyond their assimilative capacity in terms of BOD, nutrients or bacteria, although increased levels have been measured at places. There is a fair diversity of fishes, vegetation, plankton and invertebrates. Only a few measurements have been made of pesticides in the aquatic environment, and no information is available about contamination of fish caught in the rivers.
Solid waste
In general, the disposal of solid waste is under pressure, because the
quantities escalate due to urbanisation and changed lifestyles. At the same
time, disposal practices are not in place, or disposal routines and facilities
(like incinerators) are in need of upgrading or restoration.
Domestic waste and toxic, infectious or otherwise hazardous waste impose different pollution risks and disposal requirements. The two categories should be segregated at the source and handled separately.
Management should include non-structural measures. The public should be encouraged to Reduce, Reuse, Recycle and Repair the waste. In this connection, economic incentives (fees and subsidies) may be considered.
Stakeholder participation
A precondition for successful management is a joint orientation among
stakeholders, including consensus on sector objectives and strategies, and
acceptance of rules and/or practices for water sharing and water quality.
This requires in turn (i) Added value of integrated management (as compared with sector planning); (ii) active participation by stakeholders in goal formulation and plan implementation; (iii) balance between stakeholder interests; and (iv) adequate information flow.
The process should proceed through the public representative institutions (the provincial governments and the tambons). The active involvement of these institutions is a mutual advantage that can strengthen the institutions and the planning process at the same time. In many cases, NGOs are in a particular position to supply knowledge and experience about concerns, priorities and constraints that can affect implementation of the various policies.
Monitoring
Monitoring is required in order to keep the development on the right track.
Apart from changes brought about by the plan implementation, numerous other
changes will appear. These can affect both the validity of the development
objectives, the various sector goals, the supplies, the demands, and the
consequences of different courses of action. Even if there were no changes at
all, an improved knowledge can in itself put the planning in a new perspective.
A substantial monitoring is in progress under various authorities. The monitoring is incomplete, however. For example, little is known today about groundwater availability or groundwater quality.
An important objective of the monitoring is to extend the knowledge base for over-all system descriptions like the ones prepared in connection with the present project. Better knowledge will allow for more accurate estimates of (for example) the availability of groundwater, or the ecological demand of surface water. This will in turn improve the analysis of various strategies for water allocation.
Another important objective is an early identification of threats, while there is still scope for mitigation, or of new opportunities, while they still exist.