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<Technology Needs for Lake Management in Indonesia - Investigation of Rawa Danau and Rawa Pening, Java> K. Technological Requirements for Ecologically Sustainable Management of Rawa Danau 2. Particular Technological Requirements Hard and soft technology will be used for particular phases or purposes. Preliminary assessments, mapping and survey requirements If a decision is made to proceed with the implementation of the proposal to create a small dam at the exit from the caldera, then this proposal will have to be subject to the usual Environmental Impact Assessment procedures used in Indonesia in the AMDAL process. A thorough Environmental Impact Assessment will detail the possible direct effects of the construction work on the environment and will define the best methods of minimisation of adverse effects. This assessment procedure should also include such environmentally sound technologies as Environmental Risk Assessment. There are well known appropriate technologies for the control of soil erosion and for the loss of clay to the river during the construction phase. The suitability of such techniques has to be considered. The preferred positions of waste disposal and toilet facilities for construction workers is part of the preliminary planning process, as is the production of detailed maps and surveys of the area involved. During this phase much of the preparatory work for items detailed in the later sections of this report should be undertaken. All these items should be incorporated in planning and implementation documents prior to approval being given for implementation of the project. This Project is supported by IETC which is promoting the use of Environmentally Sound Technologies. While such technologies are well known and should be implemented in this project, it is important to recognise that the successful implementation of the technology depends on its incorporation in the planning process at an early stage. Initial surveys and accurate mapping of the floor of the caldera will include mapping of the areas of swamp forest and of abandoned padi fields, along with accurate height measures of the floor of the caldera. This would enable accurate mapping of the extent of any lake created in the caldera. These surveys of the floor of the caldera should allow determination of which kampungs will be directly affected by flooding, and which areas of sawah will be flooded. During the initial phase a detailed survey has to be undertaken of the exit from the caldera, including collection of samples of rock to allow estimation of the permeability of the rock, and the suitability of the area for construction of a dam. Surveys should be undertaken to determine the distribution of rare swamp forest vegetation, particularly the species of trees recognised to be of high conservation value, and to determine the extent of re-generation and seedling distribution. Surveys should be undertaken to assess the extent of soil erosion in the catchment of Rawa Danau. This should enable assessment of the appropriate sites for silt traps and check dams on inflowing rivers which should be surveyed at this time. Socio-economic surveys should allow assessment of the value to local residents of the land which would be lost if the dam were constructed, and estimation of the comparative value of fish ponds if these were constructed adjacent to the proposed lake. These would offer an alternative source of income for local residents. Educational Programs and provision of information As soon as possible after a decision to proceed with construction of a dam and to attempt to restore the lake to its former size, a concerted effort has to be made to explain the objectives of the project and its consequences to local residents. Local people living in or near the caldera will be affected by the restoration of the lake. In some cases people will lose their houses, in others they may lose much of their padi fields. It is essential to explain to these people that this is not a random action on the part of the Government. People will be compensated in various ways for the impacts on their lives. For instance, fish ponds will be provided for some people who have lost their padi fields. The educational program has to be accompanied by talks and by pamphlets explaining what is going to happen in the area. There must be talks about the nature of the caldera, the history of its drainage, and the value to Indonesia of the Cagar Alam. Training programs should deal with the use of fish ponds, the supply of fish for stocking on ponds, the work involved in acting as a guide, the need to know about the biology and ecology of the area, the objectives of ecotourism and the need for conservation. Such training programs may call for specialist educators. Trained environmental advisors should live in the area and provide on-going advice to villagers as to what is happening on a week to week basis. These advisors should have pamphlets for distribution and they should act as the information source for the people in the area. Public information centres should also be established in the local towns and cities such as Serang and Cilegon, so that people can call in and obtain information about the plans. In this way rumour and wrong information can be minimised. Requirements during the construction phase During construction of the dam, a by-pass has to be constructed to allow the flow of water down the valley of the Ci Danau river. Appropriate technologies should be implemented to minimise the amount of environmental damage during construction. Access roads should be properly constructed and sealed to minimise erosion of clay and soil which would lead to increased sedimentation at the water off-take downstream. Provision should be made for boat ramps and boat access via the sealed road to the construction site. Silt and clay traps should be established to minimise the pollution of water by runoff from the construction site carrying clay and silt. The flooding phase Due care has to be taken during this phase to ensure that no lives are threatened. Good and efficient communication, information and transport systems are essential. The rise in the height of the water has to be monitored. Water levels should be increased gradually over a five year period to allow vegetation, fauna and soil to adjust to the changed water regime, while minimising mortality among wildlife and vegetation. There is a high probability that many species of wildlife will be at risk of becoming stranded on small transient islands and drowning. These individuals should be rescued, and released either in the swamp forest, or on land near the Hutan Lindung of Gunung Tukung Gede. This will call for regular patrols by boat and vigilance by staff of the Forestry Department. During this phase local residents may find access to the swamp forest has become easier. Stealing of firewood is likely to increase along with poaching, and the collection of wildlife from transient islands. Frequent patrolling and effective law enforcement by staff of the Conservation Directorate General of the Forestry Department are essential. The early restoration phase During the initial five seasons after restoration of the lake one would anticipate that there will be large unpredictable fluctuations in the populations of animals and plants in the caldera. Aquatic plants particularly Salvinia and Eichornia are likely to spread. Outbreaks of particular species of snails and insects such as chironomids are likely to occur. During this period five or six permanent transects should be established and clearly marked. The transects should run from north to south across the area of the swamp forest. There should be regular biennial surveys on these established and permanently marked transects, to allow assessment of the effects of flooding on particular species. Data from transects should be collected and maintained in two separate centres, one being near the lake in the management offices, and the other in a research centre such as Biotrop. The transects should all be photographed from ground level at intervals of three months, from permanent markers placed on the transects. At each marker four photographs should be taken, one each in the directions, north, south, east and west. The markers should be placed on the transects at intervals of 100 metres. The transects should, as far as possible, follow straight lines through the swamp forest. The photographs should present a permanent record of the vegetation at each site and should enable staff to determine very rapidly whether the vegetation is being destroyed or not. It should enable assessment of whether the destruction is focused on particular species of trees. It should also enable assessment of whether the restoration of the lake has any effect on the growth and development of trees and other vegetation in the Cagar Alam. Socio-economic surveys should be made to establish the impact on local residents of the flooding and the effectiveness of the measures taken to alleviate consequential hardship. The value to Krakatau Steel of access to increased water supplies should be assessed in terms of economics and the cost of alternative sources. The value of various environmentally sound technologies used in the area should be assessed. These would include the introduction of fish which eat Water Hyacinth, and other undesirable water plants. Positive efforts should be made to eliminate seedlings of Mimosa pigra. The distribution of Water Hyacinth (Eichornia crassipes), and Salvinia molesta plants should be mapped. Effective patrolling and implementation of environmental laws by staff of the Conservation Directorate General of the Forestry Department are essential. Quadrats should be established at selected points in the Cagar Alam where the vegetation is accurately mapped and recorded. This would be a suitable project for students from a local University working under the supervision of a scientist from a university or from an organisation such as the Herbarium Bogoriense or Biotrop. Periodic trapping of small mammals should be undertaken at regular intervals along the transects to ascertain what the populations of small mammals actually are. This should be repeated seasonally and over a period of years to determine the effect of flooding and restoration of the lake. All small mammals should be released after determination of vital statistics. Similar traps could be established for small reptiles and for some invertebrate species, including insects and snails. These might be pitfall traps, using jars, and the animals would not be released afterwards. The monitoring program This can be seen as a phase which starts during the time when the lake is being flooded and which should continue indefinitely into the future. It will depend on the initial survey data and will build on that data to allow assessment of the efficiency and relative value of the measures suggested and implemented. It allows for positive and negative feedback on the management operations of the lake. If a particular aspect of the management of the water in the lake produces adverse effects on some of the ecological components of the caldera, then the monitoring program should reveal this fact before any irreparable damage is done to the ecosystem. Monitoring is essential in a new project such as this. Assessment of the data collected is an essential component of monitoring. Implementation of appropriate managerial responses is an automatic component of an effective monitoring system. The effects of flooding and restoration of the lake can be monitored in different ways. Some of the methods of assessment of the ecological and economic impacts are listed in the previous section. After construction of the dam and in the course of five years of seasonal flooding upstream of the dam on the Ci Danau river, new environmental issues and problems may appear. Development of tourism These new developments will include an increase in tourism and recreation, including, possibly, water skiing, sailing, and power boating on the restored lake. Tourism could be encouraged but constraints should be imposed on the area of the lake allocated for tourism and the form of tourism. The use of power boats should be prohibited as the disturbance of the sediment on the bottom of a shallow lake is unacceptable. Powerful outboard engines disturb sediments and in this lake would increase the organic content of the water, thus reducing water quality. An additional factor which should limit the use of power boats is the fact that so far no motor boats or engines of any kind are allowed in the caldera by the local people. This is a traditional religious custom which should be strongly supported. In the interests of the wildlife in the Cagar Alam it is very desirable to minimise any loud noises in the caldera. It will be necessary to define certain areas on land and on water with different conservation values, and to define the activities which would be permitted in those areas. The first area to be defined is the area of Cagar Alam or Strict Nature Reserve. This should remain largely as it is at present. Areas of the new lake within the boundaries of the present Cagar Alam should be automatically incorporated in the Cagar Alam. No access to this area by members of the public should be permitted. The gathering of firewood in the Cagar Alam by local villagers should be prevented. No fishing of any kind should be allowed in the channels and open water areas of the Cagar Alam. Persons caught fishing or hunting wildlife in the Cagar Alam should be dealt with as prescribed under the existing legislation. The fact that certain individuals have been punished for contravention of the law should be publicised by the use of notices on boards at various points of possible access to the Cagar Alam. The names of those involved should be made available to the local authorities, including the forest guards, to facilitate detection of habitual offenders. The second area to be defined should be a small area of Suaka Margasatwa, along the edge of the Cagar Alam. This should include all land on the eastern side of the new lake bordering the Cagar Alam. In open water the area of Suaka Margasatwa should extend 150 metres from the eastern shore. The area should be clearly defined with markers on land and on water and the markers must carry notices warning tourists that this is a limited access area. Thus, direct access to the Cagar Alam by people in boats on the lake should be prevented, by the creation of this band of Suaka Margasatwa. The area of Suaka Margasatwa should include the areas of swamp forest on the banks of the Ci Danau river which are at present outside the Cagar Alam. Tourism should be allowed within the area of Suaka Margasatwa. The form of tourism should be strictly controlled, and should follow the principles and practices of ecotourism. Maps and pamphlets dealing with the area and its fauna and flora should be available for tourists. Management principles should be explained in pamphlets. All tourists in the Suaka Margasatwa should be accompanied by guides, who are competent boat handlers, who know the paths and the common species of trees, mammals, birds, reptiles, fish, and insects found in the Suaka Margasatwa. Tourists should be required to stay on defined paths in the Suaka Margasatwa. Local villagers should be employed as guides and in the construction of board walks through areas of swamp forest to allow ecotourism at all seasons and under all lake conditions. No recreational tourism should be allowed in this area. The only tourist boats allowed in this area should be canoes. Fishing by line and hook should not be allowed in this area. Gathering of firewood should not be allowed, as this is an area in which gradual regeneration of the swamp forest might be expected to occur. The third area to be defined should be an area for recreational tourism. This could be a Taman Reckreasi (Recreation Park). This should be provided with facilities such as food stalls and soft drink sellers should be allowed in the area. Small sailing boats should be allowed in the area and swimming could be permitted. Canoes should be allowed and fishing by hook and line permitted. Shelters and simple permanent seats should be provided at all public parking areas and at intervals on the shore of the lake. Such shelters could be combined with native vegetation, and in particular with trees, to provide a more natural environment. Toilet facilities are essential and should be provided at parking areas. Appropriate designs for drainage should be used to ensure that effluent from the toilets is properly treated in the soil. Under no circumstances should there be any direct overflow of effluent from toilets to the lake. Large containers for garbage should be provided at these points and emptied regularly. Food and drink sellers operating in the recreation area should be persuaded, as part of their job, to use the garbage facilities and to encourage tourists and visitors to use the garbage facilities. There should be many opportunities for local employment in this area. Maps of the Recreation Area should be prominently displayed at intervals on the shore in permanent weatherproof notice boards. They must be displayed in the parking areas as well as in other sites. The position of the various facilities must be shown on the maps along with the boundaries of the recreation area. These notice boards must show the boundaries of the recreation area and provide an explanation of the function and objectives of the conservation areas. The notice boards must provide details of what activities are allowed in the recreation area, and what activities are not permitted. Potential for new levels of encroachment on the Cagar Alam The restoration of the lake will provide greater opportunities for illegal access by boat to the Cagar Alam for those who may wish to obtain wood and food from that area, as well as for those who wish to do some sport hunting. An effort has to be made to stop any such expansion of illegal activities. Using the monitoring data obtained previously, during the flooding phase, the status of particular tree species in the swamp forest can be assessed. The extent of regeneration of such species can be assessed. The spectrum of wildlife species observed can be assessed , again using data from the permanent transects. Thus it should be possible to establish whether illegal use of the Cagar Alam has increased or decreased after flooding of the restored lake. If increased illegal use of the Cagar Alam is detected it should be possible to focus increased patrol activity on those areas where the impact is greatest. Assessment of the impact of lake restoration on the local population Surveys should be undertaken to assess in what ways the restoration of the lake has affected the life of people living in kampungs on the floor of the caldera. There may be a variety of different types of effects, some of which may not be immediately apparent. The socio-economic status of families before and after the restoration should be compared to assess whether the measures taken to provide alternative sources of income for local residents have proved to be adequate. The survey should include such obvious factors as the family income and sources of income. The value of fish from fish ponds to the average family should be determined. The health of the families should be assessed to determine whether the presence of more permanent water in a new lake has affected the rate of transmission of malaria and other mosquito borne diseases. In the Mekong Basin the creation of new dams and lakes led to many cases of infection with intestinal parasites. This occurred because people were not used to having access to quantities of cheap and easily obtained fish, so were not aware of the need to cook fish thoroughly. Following the failure to cook the fish thoroughly many parasites were transmitted to the human population, including, for instance, the tapeworm Schistocephalus and various species of nematodes. Public Review and assessment of the Project Public reviews of the effects of flooding and lake restoration and an assessment of its success or failure should be held after five years and after ten years. At these public reviews, all relevant data and documents from Government and private sources about the success or failure of the project should be available. These reviews might be funded by an international body, to be responsible for the circulation of documents referring to the restoration of the lake. The results of these reviews should be published internationally to act as guidelines for similar projects on the restoration of tropical lakes. The criteria used in assessment should be based on those listed above, where comparative data are available on conditions prior to flooding of the lake. There is an opportunity for the development of new methods of assessment of such projects and for the development of new criteria for the evaluation of the success or failure of the Project. It is very desirable to establish certain criteria in advance and to retain these as markers. They must not be seen as targets, as the "target" principle, at least in some countries, means that the entire project energy goes into ensuring that the targets are met rather than that the overall project is successful.
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