tobasa geologi

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DRAFT: Not for Citation or Distribution Lake Toba

Experience and Lessons Learned Brief for12

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Lake Toba

Haryatiningsih MoedjodoPayaman Simanjuntak

Peter HehanussaLufiandi

Introduction

Lake Toba is Indonesias largest lake and the largest freshwater lake in Southeast Asia.

Located in the province of North Sumatra, approximately 176 km to the west of the provincial

capital, Medan. Lake Toba can be reached by car from Medan within three hours. By plane,

Medan is only 40 minutes away from Singapore and two hours from Jakarta, the capital city

of Indonesia.

As the largest volcanic lake in the world, the lake is approximately 87 km long from north tosouth and the width of 27 km from west to east. Located 905 meters above sea level and the

maximum depth of 529 meters, the lake is one of the countrys important tourist destinations.

The natural beauty of Lake Toba has been internationally recognized. The lakes blue waters,

gracious residents and fascinating Batak culture draw tourists from all over the globe to the

remote destination of Lake Toba1

In the middle of the lake, laid the wedge-shaped island called Samosir, thought to have

been created by subsequent upheavals between 30,000 and 75,000 years ago. This

spectacular island is one and half times larger than the entire Republic of Singapore.

Traveling from the lakes shore to the island of Samosir is a great adventure for visitors.

The Lake Toba water catchment area covers 3,658 sq km, of which the lake surface accounts

for 1,103 sq km. The remainder of the catchment area can be classified as 43% hilly and 30%

mountainous, with peaks more than 2,000 m above sea level. Biophysically, the cool and

refreshing environment, clean air, fertile soil and protein-rich resources of the region made it

as an ideal place for human settlement. No wonder that centuries ago the ancestors of the

Batak ethnic chose it as their permanent site for settlement. It was here that their descendant

developed into the five ethnic Batak groups, namely the Angkola-Mandailing, Karo, Pakpak-

Dairi, Simalungun and Toba. Samosir Island and the Toba lakeside is the site of the original

Batak culture, containing invaluable historical objects and artifacts, art and culture. In fact,

Batak culture is still alive and present here, preserved in its original form.

The unique geographical position also contained a range of economically significant sources

of livelihood for the population, mainly derived from the abundant fresh water resources and

the dense tropical rain forests. Today, the concentration of the human settlements scattered

all over the Lake Toba watershed are about 130, in the form of small villages to medium

towns. Figure 1shows the watershed and administrative boundaries of Lake Toba.

1Annette Souder, The new faces of development assistance, US Council of State Government News, June/July 1999,page 14.

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Figure 1: The watershed and administrative boundaries of Lake Toba

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The main environmental problem of Lake Toba

Population growth and development have impacted the lakes in many ways. The health ofLake Toba in Indonesia is severely threatened by pollution on the lake due to householdwastewater, oil spills from boats, trash thrown directly into the lake and streams and the fastgrowing water hyacinth that blocks access of the boats. Local people are less aware thanthey need to be of hygienic behavior, the cleanliness of their neighborhood and the need toprotect their lake which they use for drinking water and economic activities.

The untreated household wastes that mostly channeled directly into the lake and streams areconsidered as the main pollution problem to the lake. For those reason, in 1996, the

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Government of Indonesia through the Ministry of Public Works build a wastewater treatmentplant in Parapat-Ajibata town - the most inhabited towns in Lake Toba region with theinvestment of 3.2 million USD. Unfortunately, this treatment plant has never been actually useddue to lack of social marketing of the facility. Until the year of 2001, only fourteen householdsand two hotels hooked-up, whilst the facility was built with the capacity of 1,600 householdconnections. The other environmental threats of Lake Toba includes aquaculture,

hydropower, industrial water supply, polluted run off, point source pollution, toxics andwatershed

This report describes the activities, results and lessons learned of a pilot program todemonstrate ways of developing and implementing a community-based watershed actionplan. As an on the ground project that was carried out at the local level, this project is heavilycommunity-centered. Nevertheless, the government from the district up to the provinciallevel gave a great deal of support for the success of this project. The other technical supportcame from the World Bank Water and Sanitation Program in Indonesia and the Hanns SeidelFoundation (HSF).

The project history

In 2001, LakeNet partnered with the LTHF to implement a pilot project on community-basedwatershed management program for Lake Toba. The one-year demonstration program wasconducted as part of a six-year old sister lakes exchange partnership with Lake Champlain inthe U.S. The Lake Toba-Lake Champlain Sister Lakes Partnership began in 1996 with anexchange visit to Indonesia by the coordinator of the Lake Champlain Basin Program (LCBP)at the invitation of the Lake Toba Heritage Foundation (LTHF). The exchange program wascoordinated by LakeNet, a U.S.-based nonprofit organization dedicated to conserving lakesthroughout the world.

Vermont Agency for Natural Resources (VTANR), in collaboration with LakeNet applied forand was awarded a second grant in the amount of $40,000 through a special CSG/US-AEP

initiative to help bridge several exchange programs into an implementation phase. With thisbridge funding, project partners conducted a pilot program to demonstrate ways ofdeveloping and implementing a community-based watershed action plan.

The project activities as implemented

Based-on the objectives of the project, on-the ground activities that have been designedand implemented include:

Selection and training of environmental cadre

In early 2001, LakeNet Indonesia staff selected and trained ten environmental cadres within

Lake Toba watershed communities to serve as local leaders on environmental initiativesrelated to Lake Toba. Many of the cadres have demonstrated their ability to help implementand sustain activities begun during this project.

In-country study tour for environmental cadre

An effective transfer of knowledge for the environmental cadres through a two weeks in-country study tour to East and Central Java to observe and to study community mobilizationefforts and commitment-building in constructing, financing, managing and maintaining lowcost community-based sewer systems, the new low-cost composting technique in Malang,and the harvesting & utilization of water hyacinths in Cirebon and Yogyakarta.

Clean lake activities

Completion of clean lake activities along 5 km of the lakes shoreline in five communities.More than 770 people participated in these activities, some of which involved strenuous labor

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and difficult working conditions.

Training in environmental education & awareness for teachers

LakeNet Indonesia and LTHF staff and the local cadres put on a three day training workshopin Parapat in environmental education and awareness for elementary school teachers from

six regencies in the Lake Toba area using a specifically developed hands-on learning WaterModule.

Community meetings and action plans

The environmental cadres coordinated meetings involving 188 community members. Thepurpose of these meetings was to engage local residents in identifying and discussingenvironmental problems and concerns of Lake Toba and to formulate action plans to solvethe problems.

Awareness Campaign

LakeNet Indonesia and LTHF staff and the local cadres prepared, printed and distributed

25,000 copies of an information brochure in Indonesian language to promote environmentalawareness. The brochures were distributed to boat operators, and in community meetings,the utility bill office, churches, mosques, grocery stores, kiosks, and other public buildings.

The result of implemented actions

The project was implemented efficiently, and it greatly exceeded expectations in terms ofthe results and accomplishments. The most important results of the project include:

The clean lake activities by volunteers, which included the removal by hand of largepatches of water hyacinths, opened up landing areas for local fishing and ferry boats thathad been inaccessible for almost three years, at the same time they reduced invasive plant

populations. The study tour and on-the-job training (through participation in community meetings, clean

lake activities, teachers training and brochure distribution) resulted in the effective in-country transfer of knowledge to the environmental cadres. Many of the cadres havedemonstrated their ability to help implement and sustain activities begun during thisproject.

Teachers and representatives of three universities in the Lake Toba region gained importantenvironmental knowledge and educational materials.

Detailed resource inventory maps and action plans were completed in five communitiesusing a participatory approach.

New issues of concern on Lake Toba were identified for the first time, such as the increase in

the number of fish farms on the lake and their potential impact on water quality.

Citizens and the community as a whole gained awareness by participating in communitymeetings and clean lake activities.

Boat operators gained awareness of their role in environmental stewardship of Lake Toba asa result of meetings held with this important stakeholder group.

Local partners learned the benefits of involving people and working with the community inplanning and implementation activities.

Long-term, if fully implemented, the project can be expected to have social, economicand environmental impacts as improved sewage systems, invasive species reductions, trashreduction and improved local capacity will improve Lake Toba and community health, as

well as facilitating poverty alleviation.

Publication of results on the Lake Toba Online website and through LakeNets electronic

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forum of more than 900 members on lakes around the world.

Stakeholder participation

The most effective programs are those which involve citizens and other stakeholders from thevery beginning. The contribution of stakeholders involved in implementing and designing theaction are:

Grassroots

A total of almost 1,000 community members were involved in the clean lake and communitymeetings. Participants included boat operators, farmers, fishermen, small traders, vendors,housewives, and hotel owners. The ten environmental cadres were chosen from grassrootsparticipants and were central to all activities. Womenwere specifically targeted to involve inthe community meetings. The fact that 33% of the participants were women is a significantachievement due to the very paternalistic local culture. The women proved to be very activeand outspoken in the community discussion and made real contributions to the local actionplans. Many community members made in-kind contributions to the clean lake activities. For

example, one dedicated and innovative community member in East Java spent 2 days of histime to explain and show his effort in mobilizing the community to build a low-cost sewagetreatment plant and composting techniques and practices.

Government Officials

Government officials from the local Police and Sub-District (Kecamatan) Office were involvedin the clean lake activities. The Mayor of the City of Malang and his staff provided all of thefacilities needed during the study tour of the environmental cadres from Lake Toba. TheGovernor of North Sumatra gave his support to the environmental cadres before theydeparted for the study tour.

NGOs

The program was led by LakeNets Indonesia Country Director and the local staff of the LTHFin connection with local NGOs and community groups and other NGOs in the province andin Indonesia. The Hanns Seidel Foundation (HSF) provided the trainers and the environmentaleducation training materials for 41 schoolteachers.

Researchers

Three researchers who were involved in formulating an environmental education book for theelementary school children trained the teachers from the 6 regions of Lake Toba. Localuniversities surrounding Lake Toba sent their representatives to the 3 days teachers workshop.

BackgroundLake Toba is located at the center of a topographic elliptic culmination some 300 km long, asseen in the contour lines between 1001,000 m in the topographic map of North Sumatra. Thisculmination is called the Batak Tumor that runs parallel to Sumatra Island and the Lake Toba islocated at its very center. This 300 km long Batak Tumor is dissected a little west of its centerby the 1,625 long Sumatra Fault that run from the Sunda Strait to Banda Aceh. The origin ofLake Toba was first explained as a volcano-tectonic depression (Bemmelen 1949) and laterexplained as the result of a series of caldera formations combined with faulting (Nishimura,1984 and Hehanussa, 2000). The lake water body is 1,129 km2 in area, Samosir islands in thelake has a land area of 647 km2and a smaller Pardapur island is 7 km2. The lake length is 87km, its circumference measures 294 km.

The total lake basin area measures 1,783 km2

, which is surrounded by precipitous cliffs withelevations ranging between 400 to 1200 m above the lake water. The latitude and longitudeof the lake water area range between E 98o30'; S 3o05' and E 99o20'; S 2o40'. The surface

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Biomass

Table 1: Submerged macrophytes [g (wet.wt.)/m2]

Station Potamogeton

sp.

Myriophylum

spicatum

Others Total

Lotung 2,470 130 < 25 2,600Onan Runggu 2,800 150 0 2,950

Parbaloan Urat 1,833 310 520 2,663Tongging 1,947 157 < 25 2,104

Lumban Sitorus 150 1,640 0 1,750

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Hydro-meteorological features of the lake and its drainage basin

Table 2: Climate data at Balige

Mean Temp.

( oC )

Precipitation

( mm )

January 19.1 174February 20.1 167March 20.9 187

April 20.5 193May 21.0 133June 20.7 104July 21.2 71August 21.0 116September 21.0 132October 20.4 215November 20.5 188December 20.2 199

Annual 20.6 1,879

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after Nontji, 1990

Solar radiation: 15.7 MJ m2/day

The pattern of wind speed and direction varies, in January to April the wind speed can reach4m/s, in June 8.8 m/s, and in October 7.1 m/s. If strong wind blows in June to October, bigwaves as high as 1.8 m may be induced.

Surface water temperature are: Haranggaol: 27oC; Tigaras: 27; Tomok: 26; Simanindo: 27;Pangururan: 27; Nainggolan: 27; Parapat: 27; Porsea: 26oC.

Measurements for pH & COD (in mg/L) at seven stations along the coast of Lake Toba are: inLotung: 8.4 & 6.7; Situmeang: 7.9 & 6.8; Bukit: 8.4 & 9.3; Tongging I: 7.0 & 6.3; Tongging II: 7.9& 7.0; Onan Runggu: 7.6 & 7.0; Parapat: 8.2 & 8.0.

Geo-physical features of the lake and its drainage basin

The geology of Lake Toba is a challenging topic to study. The formation of this lake is theresult of a mega-volcanic-activity during the Quaternary era or the last two and a half millionyears of the earth's geological history. From a very broad analysis, this phenomenon was theresult of two major plates collision beginning during the Eosen era or 65 million years ago, i.e.the Indian Ocean or the Australian plates in the southwest and the Asian Plate located in thenortheast. This plate collision produced a long subduction zone that was accompanied by avolcanic chain along Sumatra-Jawa-Nusa Tenggara up to the Moluccas islands. In Sumatra itresulted in a large and long transform fault, the Sumatra Fault Zone (SFZ) which is over 1700km long, exposed from the Bay of Lampung in the south to the Aceh region in the northernend of Sumatra Island. Lake Toba is located not at the SFZ but some 20 km kilometer north-

east of this fault, while the Batang Toru and Renun Rivers are located and flowing along thefault.

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A wide range of reports on Lake Toba are in fields of geological, limnological, hydrological,climatological, biological, botany, fisheries, forestry, history and culture, as well as specifictechnical reports related to lake water exploitation. Scientific meetings and workshopsrelated to the hydrology, geology, water resources, sustainable exploitation, fisheries,industrial development, sustainable resource management, extreme lake water level drop,

and anthropogenic changes has been performed. Due to the large area and diverseproblems, only a very few reports provide a total overview of the lake problems.

There are reports produced by universities in Medan and the lake surrounding area, reportsby departments from the central government, annual reports from local offices or Dinas orsub-departments, workshops and seminars reports by the non-governmental institutions, andreport from meetings held by non-government-organizations. In the early 1990's geothermalenergy exploration has been executed and reported geothermal fields to the north andsouth of the lake catchment. There are international reports as result of internationalcooperation, a/o. between LIPI and Kyoto University, and between local NGO's and MonitorInternational.

A series of technical reports and books by the Asahan Authority has been produced. This was

related to the planning, construction, production, and conservation of hydro-electricity forthe aluminum smelter plant located in Kuala Tanjung in the east coast of Sumatra. Twohydro-plants each in Sigura-gura and another in Tangga plant produced a total 403 MW ofpower which in the 1980's was sufficient for the region. But lately, vast industrial and urbandevelopments turn out an increasing need for more power supply that is now supplied by anatural gas power station in the Belawan area.

Two major explanation of the lake geohistory or its origin was explained as (a) the product ofone single gigantic explosion or (b) product of multiple events. Each of these two hypotheseswas again divided or has branches of its explanation. There were lively debates on thegeological timing of the event, whether they occurred recently (less than 75,000 years ago)or were it the result of a series of geological up-doming, blasting, faulting, sedimentation, andup-wrapping which took place since 2 mill ion years ago.

Lake Toba was lately been reported as the largest caldera lake in the world. This conclusionwas based on a report by van Bemmelen who stated the lake as a volcano-tectonic de-pression. Figure 2 below shows the hypothetical diagram by van Bemmelen, 1949. Accordingto the hypothesis by van Bemmelen, the lake history started with the formation of a BatakTumor with an oval shaped, 275 km by 150 km region, located between the present WampuRiver in the north and the Barumun River in the south. The up doming produced a region withelevations up to 2,000 m shown by top of mountains such as Mt. Sibuatan (2,457 m) in the NW,Mt. Pangulubao (2,151 m) in the east, and Mt. Surungan (2,173 m) in the SE, and Mt. Uludarat(2,157 m) in the west.

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Another explanation that used a single mega-explosion origin of Lake Toba was in a report byNinkovich, 1975. Radiometric dating by K-Ar method of rock samples collected from theAsahan River valley combined with the fact that distribution of tuff (fine volcanic product thatwas air distributed) found in the Malaysia peninsula and in cores from deep sea drilling(project) in the Indian Ocean south of Ceylon, brought to the conclusion that the lake wasformed 75,000 years ago by one big-bang or one single large explosion.

In 1976 Tjia published his analyses of a rock sample taken in Tuktuk Siadong, in Samosir Island.Tjia reported and age of 1.9 million years that was accepted as the lower part of this volcaniccomplex. The rock sample shows a dense texture of welded tuff rock specimen i.e. anignimbrite was interpreted as the result of welding of hot volcanic products that has flowedas a 'nuee ardante' or hot cloud. This dense rock was the product of internal weldingoccurring in the hot tephra or volcanic products where heat was trapped during sedimenta-tion and cause welding of the tuff material which was deposited not far from the explosionvent or fissure.

During late 1960's to the 1980's there were series of international joint research in the SE Asiaregion. In north Sumatra region, from the Indian Ocean or sea-ward side, studies along theNias Island was done by Indonesia and the Scripps Institution while on-land studies in the

central part of Sumatra Island by the Indonesian Institute of Sciences and the Kyoto University.These studies have produced major scientific findings and contributed to the development ofthe hypothesis on global plate tectonics. The on land study produced reports on gravitysurveys, paleo-magnetism, radiometric dating-fission track and chronology, as well as tephra-stratigraphic studies.

Combined with previous scientific studies by Marel 1947, Tjia 1976, Karig 1978, Hamilton 1978,we came to the conclusion that the formation of Lake Toba was not a single event but acombination of complex of events. It was the product of a series of events occurring east ofthe Sumatra Fault. Other similar results were also encountered in study sites in the Lampungarea and Maninjau. These series of events occurred are closely related to the deep seatedoccurrence of the Sumatra Fault starting two million years ago. The up doming, calderaformations, lake formation, lake sediments rich in diatomaceous sediments as well as clasticsfrom fault scarps, are the product of these series of events and will be shortly discussed in thenext chapter.

The geology of the Toba and surrounding area may first be divided into the Quaternary andPre-Quaternary rocks. These Pre-Quaternary rocks are considered as the basement rock ofthe Toba Tuffs. They consist of metamorphosed limestone, shist and phylites of Carbon to JuraAge; a granite batholite of Carbon Age; and conglomerate, sandstone, and claystone ofTertiary age. These rocks are distributed at the higher mountainous areas of the surroundingToba area and on steep slopes of the lake rim they crop-out in the eastern, southern, andwestern part of the lake. They are well exposed along the easy access by road inSibagading, in Sipiso-piso, and in the Panguruan area. These rocks of Pre-Quaternary age areexposed at the faulted escarpments of the lake rim.

These Quaternary rocks have been previously described in most geological publications andmaps by one single term, the Toba Tuffs. The Japan-Indonesia joint field works and surveysduring the 1970's to 1980's revealed detailed data that came to a better volcano-stratigraphic subdivision of the rock units. The volcano-stratigraphy of the so called Toba Tuffshas been divided into detailed subdivisions as the:

(1) Post-Toba rocks and sediments(2) Toba consist of: {2a} Younger Toba Tuffs

{2b} Older Toba Tuffs(3) Pre-Toba sequences

These 'Toba Tuffs' deposits were produced in different geological times and from different

parts of the lake. To draw maps and set up stratigrahic column of these deposits, some ofthem are airborne deposits, are not always possible through the 'normal' geological methods.

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Many of these deposits are local in origin and their lateral distribution are selected orrestricted by the paleo-morphology of the area.

Toba Deposits are so called, because their occurrence was during or after the formation ofproto-toba lake. They consist of the older and the younger toba tuffs (2a and 2b). The OlderToba Tuffs consist of the Sigura-gura Formation and Lower Haranggaol Formation. These rock

units were deposited during 1.3 to 0.8 million years ago. They consist of hard welded tuffs darkgray in color. Field visits shows that their distribution were along the old Asahan valley and inthe Haranggaol area. In the Asahan valley their thickness may reach a hundred meters inthe deep paleo-valey but their lateral distribution is limited. This unit could be observed alongthe winding road between Simorea, Paritohan, ex-Sigura-gura waterfall, and ex-Tanggawaterfall.

Older-Toba Tuffs are the base of these volcanic sequences, they overlay the basement rocks.The age was measured at 2 to 1.9 million years old. This Tuk-tuk Dacite consist of a lower part,100-150 m of very densely welded tuffs that cropped out in Tuk-tuk Siadong, Samosir Island.The middle part which is 100-300 m thick is welded and shows little remains of flow structures.The upper part has the lowest welding structures, some are rather loose and still contain pu-mice blocks, and they are about 50 m thick. These sequences may be found at the steep

escarpments of the Samosir Island, near Parapat city at the Sibilating escarpment and theroad to the Partaking Cottage, and the best and continuous sequences are along thewinding road between Pangururan and Tele at the eastern rim of Lake Toba.

The Younger Toba Tuffs (2b) consist of the Upper Haranggaol Formation, Samosir Formation,Parapat Formation, and Porsea Formation. They range in age between 0.6 and 0.1 millionyears. There seems to be no distinct physical break between the deposition of Lower andUpper Haranggaol Formation. The Samosir Formation are rock units consisting of clasticsoverlain by diatomaceous sediments, some are exposed at Samosir Island. Porsea formationconsists of clastic in the lower part and diatomaceous deposits above.

The Post Toba rocks and sediments consist of the younger andesitic/ basaltic volcanicproducts formed during the late stage of a ring fault or the lake formation. They were formed

during the last 30,000 years in the northern and western ring faults in the rim of the lake. Theywere also the result of erosion and sedimentation processes during this last geologic event.

Environmental and Natural Resources

Human activities around Lake Toba are intensive with: (1) land use for rural and urban areas,(2) agricultural, (3) tourism, (4) industrial, (5) fisheries, and (6) as educational centers. Parts ofthe higher lake rim area consist of forest land with pines trees and shrubs. The western far endof the lake catchment toward the Renun River consist of (7) tropical rainforest which presentlyare partly being exploited for its wood/logging. Fisheries in the lake water and rivers wasformerly on (8) traditional local fish (ikan Toba) which was three decades ago invaded byalien-species (gurame) and lately again invaded by other fish species in fish cages breeding(ikan nila) in the lake. A (9) pulp factory and a (10) drinking water bottling industry hasdeveloped in the southern end of the lake.

Infrastructure and industries were developed during the last four decades in surrounding Tobaarea. Along the Asahan River were build three dams, one regulating dam and two powergenerating plants with construction started in 1978 and completed in 1981. The firstcommercial electric production was in 1982 used for the Tanjung Balai aluminum smelterplant that can produce 225,000 tons of aluminum annually. The energy hunger aluminumplant consumed the firm output of 403 MW of electricity produced by the two hydropowerplants along the Asahan River. A pulp factory was build a decade ago at the mouth ofAsahan River west of Porsea and bottled drinking water plant was reported in the Balige

area. Agricultural activities produced fruit and vegetables for Medan area and export toMalaysia and Singapore, pineapple and tea plantations, markisa plants, and onion grows

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well on the slopes surrounding the lake. A relative smaller in scale activities are cattle andpoultry. Flowers are grown in the high elevation areas in the northern part of the lake.

Table 3: Land use in the catchment area (1981)

Natural

Landscape

Area (km2) ( % )

Grass (alang-alang) 955.00 40.6Scrub 59.24 2.5Forest 159.66 6.8Reforestation 388.70 16.6Regreening 228.28 9.7Agriculture land 512.08 21.8Plantation 20.88 0.9Others 23.56 1.1

Total 2347.50 100.0

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Main type of woody vegetation: Tropical high mountain forest, Pines merkusii forest,Macadamia hilbrandii forest

Main type of herbaceous vegetation: Imperata cylindrica with Rhodomyrtus tomentos,Melastoma sp., and Gleichenia linearis

Main kind of crops: rice, sweet potato, maize, vegetables

Level of fertilizer application on crop fields: moderate

Political and Socio-economic Features

The establishment of Regional Autonomy Act has some impacts on the political, social and

economic condition to the local governments, including the Lake Toba region. Throughregional autonomy, six districts in Lake Toba region have a larger authority in themanagement of their area, including in preserving the Lake Toba region. Other than that,local governments also have a better chance to work directly with the internationalagencies.

The jurisdictional features

Based on Act No. 22 year 1999 on Regional Autonomy, the Province is responsible tocoordinate certain issues involving two district or more. In this case, the management of LakeToba involves 6 Districts: Toba Samosir; North Tapanuli, Simalungun; Karo, Dairi and HumbangHasundutan. Lake Toba has also indirect influences on two other Districts, namely Asahan

and Tanjung Balai which are located at the down stream of Asahan River.

Administratively, by far the largest part of the Lake Toba water catchment area (87%) issituated in the North Tapanuli District (Kabupaten, or District), with the balance dividedamong the regencies of Simalungun (8.4%), Karo (2%) and Dairi (2.5%). Naturally the NorthTapanuli District also houses the largest part (81%) of the total 517,050 inhabitants of the LakeToba water catchment. The same district has also the highest population density, with 185people per sq km, followed by Simalungun (l4l people per sq km), Dairi (93 people per sq km)and Karo (57 people per sq km).

The political significance and implications through its history

Lake Toba region has been proposed by UNESCO to be designated as a Biosphere Reserves,focused on three main activities: conservation of bio-diversity; economic and socialdevelopment; and preservation of associated cultural values. With the biosphere reserves

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status it was expected that Lake Toba will receive international attention and inviteinternational participation in its development and preservation.

According to the Act No.24, 1992 about the Spatial Planning, the Biosphere Reserves isidentical with Special Region, a region with prioritized spatial planning. Designation of aregion as a Special Region needs a Presidential Decree. Two aspects that have to be

considered if Lake Toba region will be designated as a Special Region through PresidentialDecree are:

- The spirit of the Law No 22 of the year 1998 should be obviously reflected with theemphasize on community empowerment in the development process and preservationof Lake Toba region.

- The availability of adequate instruments for the implementation of the PresidentialDecree.

The last aspect become very important to be considered in designating Lake Toba asSpecial Region in view of the fact that in Indonesia the implementation of a policy with or

without juridical status are very weak. This situation could make the policy in designating LakeToba as special region turn out to be meaningless. Some examples of the weak policyimplementation in Lake Toba region are:

- In 1990, the provincial government of North Sumatra issued the regulation of themanagement of Lake Toba region which prohibited the building construction withintens of meters from the shoreline. This regulation have never been implemented, it wasloyally stayed in the librarys bookshelf for long time.

- The government had issued Presidential Decree No 96 of the year 1998 concerning theprohibition of foreign investment for aquaculture in inland waters. Obviously, most of thecage aquaculture in Lake Toba is owned by foreign investors.

The past social and economic development history and trends

Lake Toba is the major ecosystems of North Sumatra, a priority region for developmentplanning in Indonesia. The primary economic sector (64%) in Lake Toba region is agriculture,mostly rice field as rice is the staple food in the region. Forest and plantation (cocoa, coffee,and tea) are other main natural resources that have been contribute to the economy of theregion beside tourism due to the beauty of the lake and culture that surround it. The blendbetween scenic beauty of the region with its ecological significance on the one hand andthe fact that the area is the site of the original Batak culture on the other is an eco-culturaltourism attraction worth further development in the future.

In the period of 1996-1997, the number of foreign tourists visiting Indonesia has been

increased significantly, from 596 million to 613 million people. Along with the economic crisisthat hit Indonesia in 1998, the number of the incoming tourists to Indonesia has beendeclined, including to Lake Toba region. The number of incoming foreign tourists to Indonesiais still far below its number to Singapore, Thailand and Malaysia, even though Indonesia haslarger tourist area and attractions. The tourism potential in Indonesia has not been optimallymanaged.

The economic potential of the region first became significantly obvious in 1982 with theconstruction and operation of PT. Inalums aluminum plant. The plant required large amountof electrical energy, which is obtained very economically by PLTA Asahan (hydro-electricpower generation) through utilizing the potential energy of the lake water resulting from theheight differential between Lake Toba and the foothill region. Since 1985, PT. Inalum spends

2.6 million US dollars for the use of Lake Toba conservation programs. This Inalums annual feewas provided as a contribution for the Lake Toba preservation since they have used the LakeToba water to support the operation of the aluminum factory. The fund has been prioritized to

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be used for the management of critical land in the Lake Toba watershed, Asahan River andthe District of Tanjung Balai.

The forestry potential was also developed since 1985 with the presence of Indorayons pulpmill and rayon plant, using, as raw material, wood from the forests in five kabupatens(districts): Dairi, Karo, Simalungun, North Tapanuli and South Tapanuli. The operation of

Indorayon was based-on the Joint Decree signed by the Research Minister andEnvironmental Minister to give the green light for the plants construction and operation in1986. Indorayon has produced 1.8 million tons of pulp within ten years, during the period of1988 to 1998. Whereas from 1993 to 1998 it has produced 0.25 tons of rayon fiber as the rawmaterial for textiles. These productions were estimated to have consumed around 10 millioncubic meters of wood. Indorayon has offered 1% of their net income or about 6.6 billionrupiahs to the Toba Samosir District to be used for the environmental management.

Institutional and Managerial Features

Preservation of the Lake Toba region as the natural resources that has the values, function,

and benefits for its inhabitants depend on who and how the lake is managed. Until now, LakeToba region has no management committee that is administered in a conceptual,professional, systematic, and integrated way, taking into consideration that this lake coversthe area of six different local governments.

The political, legal and institutional frameworks

The concept of management committee for Lake Toba has been proposed by variousstakeholders, from government, private sector, NGOs up to the community which aimed tothe optimal development and preservation of Lake Toba. It has never been materialized, dueto different perceptions and interests among the stakeholders. The formation of themanagement committee for Lake Toba is vital for the coordination of the stakeholders.

The absence of the management committee led to the absence of the agreed vision on thepreservation efforts of Lake Toba region. All efforts or activities were partially conducted bygovernment, NGOs, private sector and community groups. As the result, the impact of theseefforts is too small to be recognized. More than that, the character of the program that tendto be a crash program shows the lack of planning and sustainable implementation of theprogram.

Nevertheless, the absence of the Lake Toba management committee not becomes aconstraint for the cooperation between some active NGOs with various internationalorganizations such as:

- Based on collaborative work carried out by UNESCO with the Lake Toba HeritageFoundation during 1996 and 1997, three field projects were launched in the Lake Tobaarea from 1998 into 1999 that focused on communication and education to build localcapacities for community-based conservation/alternative income generation.

- Lake Toba has joined LakeNet, where numbers of large lakes allover the world isinterconnected for the integrated sustainable lake management.

- Cooperation with Hanns Seidel Foundation for the capacity building in the Lake Tobaregion through practical environmental education for the youths and elementaryschool children.

Due to the lack of the management committee, all of those cooperation efforts were notadequately disseminated, the progress of the efforts were hardly recognized, especially by

the government agencies and other organizations.

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shoreline that was also included in the LakeNets watershed management pilot project. GKPSmade a good progress in its Environmental preservation in Nagori Sihalpe village. Thesuccess of the villages tree planting won the first award in the Simalugun DistrictsEnvironment Day and received a badge of appreciation from the President of Indonesia.Success is also on organic farming, cage fishing and waste management in the villages.

There are certainly some more activities at the grassroots level in Lake Toba region that hasbeen implemented by other NGOs or community groups. Unfortunately, there is no record onthe numbers of active NGOs in Lake Toba region moreover an adequate documentation orreporting system of their programs as a reference. For those reason, in early 2000, UNESCOsponsored a national workshop on Strengthening communication and local capacities forcommunity-based participatory environmental management of Lake Toba in Samosir Island.This workshop was administered by LTHF, 20 out of 70 participants are representative of localNGOs. The rest were representative of universities, LIPI (Indonesian Research Institute), localgovernment agencies, press and international agencies i.e. UNDP and UNESCO.

The final report from this workshop included a comprehensive directory of local NGOs that willbe further updated in an UNESCO Lake Toba Handbook for sustainable natural resource

management.

Biophysical Environment

The changes in Lake Toba region such as the reduction of the water level and pollution of thelake affected not only the social and economic situation of the region, also affected thebiophysical environment.

Past and Current Conditions

Currently only 70 out of 202 rivers that discharge into Lake Toba flow all the year round.According to historical data studies by Sastromijoyo, 1990, the discharge from Lake Tobahave shown a decrease during three phases:

Period 1920-1932, average inflow discharge to Lake Toba was 110.4 m3/s Period 1957 - 1975 average inflow discharge to Lake Toba was 104.4 m3/s Period 1976 - 1988, average inflow discharge to Lake Toba was 90 m3/s

Water level of Lake Toba between 1984 and 1987 suffers a continuous decline in water levelof 2.5 m. The outflow from the lake is used for power electric generation which provides solesupply to an aluminum smelter.

The rainfall data are too poor a quality to show whether there has been any significantchange, but indications are that a decline of the order of 10% may well have occurred.(Anonym, 1990). Other factors such as land use change may have contributed to thechange.

The first topographic map of the lake region was measured in 1887 by F. van Brenner and vanMechel. In 1909 and 1913 the Porsea and Siruar region was washed by severe floods. Theseevents were followed in 1915 by the blasting of Batu Bongbong near Siruar that haveobstructed the Asahan river flow. In 1918 it was first planned by the Dienst voor Waterkrachten Electriciteitto construct a hydropower plant in the Asahan River. After several failed workplans, in 1978 physical work started for building the Sigura-gura underground power plantfollowed in 1979 for Siruar regulating dam located upstream. The work concluded at end of1982 by the operation of Tangga hydropower plant which is located downstream of Sigura-gura on the 1st of January 1983.

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History of lake degradation1

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In December 1957 the lake water level stood at 905.61 m. In December 1987 it was at 903.65and in 1990 mi was 902.70 m. Because of this continuous lake level decline the AsahanAuthority reduced water flow to the hydropower from 102 to 82 m3/s. This decreaseconsequently have an effect to the aluminum smelter production lines in Kuala Tanjung, an

investment of 2 billion USD, from 225,000 to 185,000 ton/y. The cause of this water leveldecline is unknown whether it is geologic of origin, climatic change, or increasingevaporation due to land use changes.

Pollution from domestic waste has affected the water quality of the lake. In the 1970s therewere no signs of water hyacinths on the lake but since 1990s they were observed in theParapat area. Secchi disk reading of the water column in the center of the lake in 2001 was11 m while in the Bay of Parapat near the Ajibata harbor it was less than 2.8 meters. Fishcage culture started to develop since mid 1990 and has contributed to the pollution of thelake water. Now, in the year 2003, north of the Bay of Sigapiton, in Tomok, Simanindo, andPangururan at Samosir Island, and in Haranggaol there were extensive fish cage culturedevelopments.

At the mouth of Asahan River a pulp and paper factory was build in south Toba area, at alocation between Porsea and Siruar regulating dam. Rejection by local population becauseof the smell produced by the factory have temporary closed the plant. The plant wastemporary shut down and is now reducing its total activity to only producing pulp with apromise to provide better waste water treatment plant.

Lake and drainage basin resource conflict

Introduction of alien fish species.Local government/farmers have introduced fish of alienspecies that will infiltrate (swim) into the whole lake area. These alien species have toadapt to their new ecosystem. Adapt might also mean will dominate the ecosystem. Theother problems came from the cage aquaculture. The fish food poured into the lake adds up

the water pollution problems. The cage aquaculture owned by foreign investors such as fromSweden is estimated to reach 150,000 units. There is no data on the community own cageaquaculture.

The construction of a hydropower plant. The construction of the hydropower plant south ofSilalahi at the west coast of Lake Toba took water from Renun River that flows some 13 kmwest of the lake. This is an example of interbasin water transport that has not been sufficientlyexplored on its Physico-bio-chemical effects. It will transport a minimum of 7 m3/s water thatfall from the lake rim down some 300 m to produce 90 MW of electricity and add additionalwater to the lake.

The construction of pulp and rayon industry, Indorayon. A pulp and rayon industry wasconstructed in Porsea village of Toba Samosir District with the investment of 40 million US

dollars. The Indorayon plant required 400,000 cubic meters of water per day for processing,which was taken from the Asahan River. The used water was returned to the Asahan River,undoubtedly mixed with various toxic materials derived from the processing chemicals andsubstance originated from the wood, as well as substance produced from the reaction ofboth sources of chemicals. Of particular concern are toxic substances of the AOX category(Adsorbable Organic Halides), such as dioxin, pentachlorophenol and trichlorophenol. Theseare the sources of substances in the liquid effluent.2

Apart from the above toxic substances, during the processing of pulp, rayon, and theproduction of process chemicals, various gases and vapors were released into the air, themajority of which were toxic and foul-smelling. Although at that time the most objectionableeffect felt by the community was the odor, over the long term, the toxic effect is the most

2 The impacts of PT. Inti Indorayon Utamas Operations on the Environment of Lake Toba, LTHF, 2000, page 6

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alarming. The majority of gasses released from the pulping process is collectively known asNon Condensable Gasses (NCG), especially H

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2S and MMC (Methylmercaptan).

However, from the beginning, the presence of Indorayon was felt to bring negative impactson the natural surrounding and the human population, in the form of damage to theecosystem of Lake Toba region and sufferings to the community living in the area. These

impacts have, of late, become more oppressive, which must be monitored and managed inan integrated and professional manner in order to alleviate human sufferings and preservethe environment of Lake Toba region.

Management Environment

The preservation of Lake Toba is closely related to the other aspects, including the peoplesbehavior and the local culture. In ecology, which meant the rules in a household is not onlyconsists of the house itself, but the people who live in the house and their activities are alsoincluded. The meaning of ecology has to be thoroughly understood by the businesses,beaurocrats and the lakes community. A numbers of factors that led to environmentaldegradation of Lake Toba region are:

The spatial planning of Lake Toba region has not been adequately addressed.

Imbalance outflow of water, due to the total volume of water that has been use forAsahan hydropower is far beyond the water inflow to the lake and the obstructedhydrological cycle due to the deforestration.

An environmentally friendly effort in increasing the productivity of land has not beenimplemented yet.

Lack of a thorough understanding about the local socio-cultural characteristics that ledto the pollution of the lake due to the waste disposal both from the household and

industries; the use of chemical fertilizer; and the cage aquaculture.

The fast growing water hyacinth.

Lake Management Programs and Processes

The local regulation about the Management of Lake Toba region has been issued by theProvincial Government of North Sumatra in 1990. However, the spatial planning of Lake Tobaregion has never been developed. The preservation efforts were implemented independentlyby the government, NGOs, private sectors and community groups. Some of the preservationprogram that has been done in Lake Toba region is among others:

The plan to create the Lake Toba management committee as a vehicle to develop avision which then elaborated in the spatial planning of Lake Toba region agreed by allof the stakeholders.

The water quality of Lake Toba has been deteriorated during the last decade; thereforere-forestration has been selected as the priority. The reforestration program covers 50%of the total area of Lake Toba region.

Promote the organic farming system to discourage the use of chemical fertilizer.

Increase the awareness and community involvement in the preservation of Lake Toba.

Management of the household and industrial wastes.

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The physical development in Lake Toba region has created some negative impacts for theenvironment. The negative impact that could be easily detected is the degraded waterquality due to the wastes generated from the developed area that were channeled directlyinto the lake.

Parapat-Ajibata wastewater treatment plant.Parapat is one and the busiest tourist center inLake Toba region. The tourist area of Parapat located on the shores of Lake Toba has an areaof 140 hectares. The planned residents total 16,000 not including the tourists themselvesincreases the problems of sewage from households and businesses. Almost all of theuntreated household waste disposed directly into the lake. The quality of water has beenreduced to the point that it is necessary to institute immediate steps to solve the problem withthe construction of a waste water treatment plant. In 1994, water quality in the surroundingrivers exceed a level of pollution with a measured amount of 28 mg/l BOD (5 mg/l isconsidered good) and is estimated to increase 1.5 times by the year 2010. The level ofpollution in the lake along the shore is 6.9 mg/l to 52.2 mg/l BOD and is estimated to increase1.5 times by 2010.

The development of the sewerage system was started from the dense population around thelake, the area of hotels and restaurants by using a conventional sewerage system. Thewastewater from households, hotels and restaurants channeled to a main wastewater pipe.From the pipe it is then processed and put into the aeration ponds. Construction of theParapat-Ajibata wastewater treatment plant began in the month of October 1994 whenfunds from an OECF sector loan in the amount of 7.3 billion rupiahs equal to 3.2 million US$was available. Most of the constructed 1.5 km main and secondary sewer pipes located atthe Parapat sub-district of Simalungun Regency while the 2,010 m3 capacity of sewagetreatment plant with aerated lagoon system located at Ajibata sub-district of North TapanuliRegency. This facility is equipped with pump lifts at three sites each with a capacity of 60-l/second and 5.3-m head, and with a pressure pump in one site with a capacity of 60

l/second and 41.94 m head.

The Parapat-Ajibata treatment plant was constructed with the capacity to serve 17,400people with an addition of about 4,500 tourists per day in the high season. Due to the lack ofthe social marketing of the facility, only 2 hotels and 14 households were connected. Lakespollution due to the untreated domestic wastes is households and community issues, and,thus requires recognition of specific situational social and cultural factors.

There is no data on the investment for the reduction of lake stresses that were channeledthrough the NGOs working in Lake Toba region. Nevertheless, the fund from various sourcesfor all of the program implementation in Lake Toba under the sister lakes partnership betweenLake Toba and Lake Champlain, including the program implementation at the grassroots

level that has been invested is 129,000 US dollars.

Environmental Status

The water quality in Lake Toba during the last few years has been obviously deteriorated. Theoil content of the lake water reached the level of 7.5-35 mg/l. biologically, the lake waterpollution obviously indicated by the evidence of pathogen bacteria such as faecal coliformof 1,000 mpn/100ml and total coliform of 20,000 mpn/100 ml of water.3The Parapat-Ajibatawastewater treatment plant seems to be a wasted investment, unless a pro-active socialmarketing of the facility were implemented. Maintaining a clean environment is one aspectof the Lake Toba watershed management program which is highly related to the behavior of

3Parlagutan Siahaan, Pesan danau Toba (Message from Lake Toba bulletin), September 1999, page 8

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the people in the surrounding communities. The way the community treats its environmentdepends on its level of understanding and knowledge.

Enabling Environment

The visions of the Lake Toba preservation that were agreed by all stakeholders become acritical point that has to be solved. With this vision there are a number of expectedadvantages for the preservation of Lake Toba, i.e.:

The efficiency of allocated resources for the preservation efforts of Lake Toba region

The impact of existing efforts on the preservation of Lake Toba could be easilyrecognized by the community

Law enforcement is expected to be improved as it is supported by all stakeholders

In order to formulate a decent spatial planning of Lake Toba region which based-on theagreed vision, there are needs to conduct some research and obtain the complete anaccurate data. The availability of adequate and reliable data is very important for the holistic

approach of the preservation of Lake Toba that led to the success with significant impacts forall of the stakeholders.

The increase in awareness and community involvement are not limited only on theimplementation stage but has to include the preparation and design of the programs. With adialogues approach that combines the bottom-up and top-down approach in the programpreparation, it is expected to increase the community commitment in the preservation ofLake Toba. The cooperation with international organizations has to benefit all sides involved inthe program, mainly the community. Therefore, there will be more effective result of thecooperation.

From the institutional aspect, the Presidential Decree about the Management of Lake Toba

Region was almost signed on March 15, 1999 when the President planned to visit Lake Tobato launch the tree planting program. The concept of the Presidential Decree was drafted bythe Department of Tourism, Art and Culture. The socialization of the draft Presidential Decreeto the related stakeholders raised different perceptions amongst them and led to adisagreement which became the reason for it to not being signed by the President. The maindiscrepancies in the perception towards the concept of the Presidential Decree were amongothers:

The Lake Toba region will never be designated as conservation area where the Batakpeople could not do anything in their own land. However, some parts of the Lake Tobaregion such as the steeply sloping riverbank or mountain side which are critical tolandslide have to be protected.

The Lake Toba region do not refuse the existence of industries, on the contrary it invitesthem for the shake of the regions prosperity. Only industries with negative impact to theenvironment that will be rejected.

The planned Lake Toba Management Body (LTMB) is not an authority or the like; butan institution responsible for coordinating the planned programs; implementation of thepreservation program; harmonious development of Lake Toba region; and serves therespective five regencies by providing high level human resources also in-country andinternational networking capacity.

LTMB is supposed not become a new beaurocracy in Lake Toba region, it has to be aninstitution that encourage the local community participation even internationalcommunity to dedicate their maximum efforts to Lake Toba through information,coordinative support and real case.

LTMB is not a new superior of the respective five Bupati (Head of the Regency) or aninstitution that takes over the authority of the local government, but a partner that is

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able to assist in integrating the use of various natural resources.

LTMB do not have the intention to designate Lake Toba region as the Worlds Heritagesite since its create more disadvantage than the advantages. The more suitable statusfor Lake Toba region is as a Biosphere Reserves.

LTMB will not only be partnered with the government, but with all of the stakeholders:

governments, NGOs, local organizations, traditional society, industries, universities, press,churches, international agencies, investors and individuals.

The accountability and transparency in financial management in the preservation of LakeToba region is a must. The experience in the past where the financial aid of 50 billion rupiahsor about 5.8 million US Dollars per year (current exchange rate of Rp.8,500 per USD) from PT.Inalum that was intended to be used for the preservation of Lake Toba has gone with thewind. Since 1982, the Inalum Company has the obligation to the Department of Finance topay an annual fee of 5.8 million USD, based-on its production and the price of aluminum atinternational market. The use of this financial aid was unclear.

Despite the pro and cons about the Lake Toba management committee that never beenmaterialized, the Governor of North Sumatra, in 2002, has established the Coordinating Boardfor Lake Toba Ecosystem Preservation. The structure of the Board is based on ex-officiorepresentation i.e.: chairman (Governor of North Sumatra); vice-chairman (vice Governor ofNorth Sumatra); secretary (Head of Provincial Environmental Impact Management Agency);vice-secretary (Head of Provincial Planning Board); and members (representatives of the 8Districts, representatives of LTHF and representatives other NGOs)

The Coordinating Board has the following functions of coordinating the environmental controlof the Lake Toba ecosystem; monitoring the environmental impacts of the Lake Tobaecosystem; coordinating the environmental quality recovery in all Districts surrounding LakeToba; and mobilizing peoples participation for the conservation of Lake Toba ecosystem.

Under the board, the governor also established a Technical Advisory Committee, consists of:Head of Provincial Environmental Impact Management Agency as the chairman; Head ofProvincial Planning Board as the vice chairman; Deputy Head of Provincial EnvironmentalImpact Management Agency as secretary; and the relevant provincial Technical Agenciesand Bureaus also the Asahan Aluminum Authority as members.

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Figure 3:

Organization Structure of Coordinating Board

for Lake Toba Ecosystem Preservation

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Key Lessons Learned

If environmental policies are to make an impact at the community level, it makes sense to

conduct research at the community level and to involve the community as the majorstakeholder to the possible extend.

During the past three decades, the government of Indonesia has used centralized, top-downapproach in many development sectors, resulted in lots of abandoned infrastructures andfacilities with large investment. The political changes in 1998 have created a biggerautonomy for the provincial and the local governments and so opened a wider chance forcommunity direct involvement in development activities.

Community-based activities with profound participatory approach such as this one hopefullycould bring into the policy development process the voices of usually excluded principalstakeholder group the community. From the experiences of this project, policy makers can

draw insight what works and why, and use that knowledge to create strategies to bridge thegap between national policy and local practice.

From the experience of applying a community-based approach to manage a large lakewatershed in a developing country, a number of key lessons have emerged both on thesuccesses and failures, led to a more interesting learning of what might we have donedifferently with hindsight. The project partners believe that the experience and knowledgegained from this project has important implications for the future of Lake Toba as well as otherprojects in Indonesia and beyond.

Sustainability

Changing attitudes and behaviors, involving citizens and stakeholders, raising awarenessabout environmental issues and reaching consensus in a community on a vision and actionplan are all aspects of successful watershed management that take time and require andongoing effort. A community-based approach offers the most promising strategy forsustainable watershed management of Lake Toba. Whether planning a wastewatertreatment facility, solving water supply problems, implementing measures to improve waterquality or trying to change personal hygiene behaviors, the most effective programs arethose which involve citizens and stakeholders from the very beginning and are relativelysimple and low-cost to implement.

The main obstacle to project sustainability is the security of funding, both to implement the

water action plans that have been formulated by the communities, and to replicate theactivities in other area of the region. The program is highly replicable, and the methodology isalready being applied in eight other lake regions throughout the world through a LakeNettechnical assistance and exchange program. This community-based program provides anoutstanding example of moving from vision to action as described in the Framework forAction.

Partnership, participation and stimulating ownership

The involvement of environmental stakeholders at all levels is indispensable, one of thembeing the grassroots community. The Lake Toba watershed management is impossible

without the involvement of the communities living in it.

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The adoption of participatory approaches into the development projects in Indonesia hasbeen increasing over the past several years. Field observations have convinced many,including development practitioners, that the participation of the client community in thedecision-making process greatly influences the implementation and sustainability of theproject. The participatory approach is an effort to solve common problems through buildingand use of community knowledge upon matters related to the problem. The dynamic,

demand-based and change-oriented participatory approach improves care and capabilityof the community by giving them skills to analyze and solve their own problems. Theparticipatory data and information collection and inventory process by the communitystimulates the sense of belongings and involvement in the implementation of the plan theythemselves developed.

However, the community alone could not solve all of the environmental problems since manyparties from the government, businesses, industrialists, researchers, environmentalist evenpoliticians has their own interest in Lake Toba region, there should be a willingness tocommunicate to each other and work hand-in-hand in saving this worlds treasure.

Community motivator

Community members are the best influencers and communicators for change. People aremore easily convinced by their neighbors experiences and tend to trust those they live withrather than outsiders. When a new facility such as the community-based wastewatertreatment plant is introduced, its pros and cons must be fully understood before it getsaccepted. Explanation by outsiders may serve to inform people, but they trust and acceptthe information to be true only when a relative, neighbor or a local leader checks it out andconfirm it.

Many of the ten environmental cadres who were selected from the local respectivecommunity included in the project have demonstrated their ability to help implementactivities begun during this project. However, the sustainability of their willingness to be the

community motivator after the project is over could not be guaranteed as it is a very highdedicated work. A more thorough selection process of the environmental cadres as theindigenous potential change agents is needed. At least three months or more is necessary todevote to the exploration of the dedicated, committed and trust worthy indigenous potentialchange agents. A scheme of small incentives is important to support the environmentalcadres for the time and energy they devote to promoting environmental awareness andinitiatives.

Resource availability

There is a considerable resource, initiative and understanding of Lake Toba environmentalproblems amongst professionals, at all levels: national, provincial and district. Appropriate

processes and opportunities are required, for this resource to be tapped and its potentialrealized. Many researches have been done, which unfortunately have not been widelydisseminated moreover understood by the community as the principal stakeholders. Theyneed to be translated into a more communicable and understandable language for thecommunity.

Recommended initiatives

Implementation of the community action plan

The community action plans that have been prepared by the community need to beimplemented. The real participatory process in preparing the community action plan is the

seed of sustainability that need to be maintained. The unmet expectation of the communitythat usually happened in the past has to be avoided. If the community is successful inimplementing their action plan with a little financial and technical support from outside it will

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become a very good real example that could trigger other community to replicate theprocess.

Continuation of environmental education training

Behavior change does not happen until people realize or experience the benefit resulting

from the change. Behavior can be said to have changed only when newer behaviorpatterns replace older one consistently and are sustained thereafter. Measuring the changeof behavior as a result of environmental education of schoolchildren would certainly take avery long time, but the results can be far more effective and sustainable.

Training for the elementary school teachers on the practical environmental education (PLH)have to be continued and expanded to cover more teachers and community leaders inLake Toba region. The implementation of environmental education is a very appropriatemeans for raising awareness at the elementary school level because the subject is filled withsocial, cultural and ethical norms that are most likely learned in the structured environmentfound in schools. PLH is urgently needed to help students develop an attitude of caring forthe environment and avoiding behaviors that hurt the environment in their early years. PLH

can also help students begin to realize that they themselves are an inseparable part of theenvironment and to feel a sense of stewardship and moral commitment to environmentalconservation.

Environmental education at the elementary school level is not an independent subject at thecurrent time. It is generally taught as part of other subjects such as social science, naturalscience and family welfare. As a result, environmental awareness tends to be low amongschool-age children. At the later stage, mainstreaming the PLH into the local curriculum ofenvironmental education would be a great advantage for the health of Lake Toba.

Support the LTHFs Clean Lake Activities on an ongoing basis

Global Environment Facility invested $750,000 in the control of water hyacinths on LakeVictoria with limited results to show for it. In this project, clean lake activities in five keyshoreline areas cost less than $2,000 and yielded tremendous results, both in terms ofimprovements in the environment and a heightened awareness in the communities. Themain difference between the approaches on these two lakes was the application of a hand-pulling technique on Lake Toba versus mechanical and other techniques on Lake Victoriawhere the problem is said to be much more severe. Even so, a simple, community-basedapproach works in the case of water hyacinths on Lake Toba.

Create the Lake Toba Science & Education Center

Declining environmental quality, including water quality degradation due to untreated

wastewater entering the lake, is evident in the region. A better informed and more involvedcitizenry and improved cooperation among the numerous public and private stakeholders inthe region are key to successful implementation of conservation and sustainabledevelopment initiatives. Creating a center which can serve as a clearinghouse of informationand place for learning about Lake Toba will be an important step toward addressing theseneeds for the region.

Establish a research and monitoring program for Lake Toba

Until today there is no research and systematic monitoring program has been established onLake Toba. Several research studies have documented some of the basic characteristics ofthe lake and watershed, but these have been exclusively reconnaissance surveys. Along with

the development of educational programs for the Center, a plan should be developed for aresearch and monitoring program that would be conducted at the center and throughpartner institutions.

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