1. Geographical Location and Area of the Lake
Lake Batur is an active caldera lake which is located at an altitude of 1,050 meters above sea level (asl). Geographically, Lake Batur is located at a position of 115o 22’42.3 “- 115o 25’33.0” East Longitude and 8o 13 ‘24.0 “- 8o 17’13.3” South Latitude. The surface area of the lake water is 16.05 km2, with a water volume of 815.38 million m3 and an average depth of 50.8 m. Lake Batur water comes from rainwater and seepage water from the surrounding mountains with a catchment area of 105.35 km2 (Umber: Bapedalda, Bali Province, 2004).
The length of the coastline (shoreline) of Lake Batur is approximately 21.4 km surrounded by land with two different topographies, namely in the western part it is a wavy lowland to a mountain (Mount Batur with an altitude of 1,717 meters above sea level) and in the north, east and south is an area of steep hills to mountains (Mount Abang with an altitude of 2,172 meters above sea level). As a water resource system, the waters of Lake Batur contain potential biological and non-biological resources that have not been adequately recorded and inventoried in the context of empowering them for the development of agricultural and fishery activities in general waters. The development of agriculture and fisheries in Lake Batur has a strategic meaning in the context of empowering the economy of the people around the lake.preservation of lake biodiversity and tourism development.
2. Climate
The area around Lake Batur is influenced by a tropical climate with two seasons, namely the rainy season which is marked by the blowing of the wind? West Monsoon? and the Wind-influenced Dry season? East Monsoon. The average daily wind speed per year is 0.62 m / sec.
3. Rainfall
The rainy season starts from December to May. The total annual rain averages 1,838.60 mm. Rainfall in December 2010 in the Kintamani area>
500 mm.
4. Air temperature and humidity
The condition of Lake Batur water temperature ranges from 22.8 – 26.60oC and the average annual relative humidity is 87.67%.
5. Hydrology
The water cycle or hydrological cycle is the continuous circulation of water from the atmosphere to the earth and back to the atmosphere of condensation, precipitation, evaporation and transpiration. Warming lake water and sea water by sunlight is the key to the process of the hydrological cycle which runs continuously. Water evaporates, then falls as precipitation in the form of rain. Lake Batur water comes from rainwater and water seeps from the mountains
6. Topography and Land Use
a. Topography
Lake Batur is located between 1,000 m above sea level. The topography is wavy to mountainous, with the physiography of the area including the caldera and volcanic valleys. Most of the slopes are relatively steep to very steep. Flat slopes with a steepness of less than 3% (0-3%) are only found around Lake Batur (Kedisan and Buahan Village), the rest are slopes that are slightly sloping / wavy (8-15%), sloping and hilly (15-30 %), rather steep (30-45%) and very steep (> 65%).
In the western part of Lake Batur is a low, undulating plateau to the mountain (Mount Batur with an altitude of 1,717 meters above sea level) and in the North, East and South it is a steep hilly area to the mountain (Mount Abang with an altitude of 2,172 meters above sea level). Meanwhile, based on the height above sea level, Lake Batur is located between 1000 m above sea level and the highest land is located between 3000-4000m above sea level.
b. Land Use Administration
The land area around Lake Batur in 2007 was 11,787 ha, which was used for:
– Tegalan: 5816.5 ha (49.35%), for cultivating vegetables and food crops.
– Plantation: 540.7 ha (4.59%), between 1997-2007 there was an increase in land use for plantation land for plantations reaching 18.55%.
– Community forest: 634.5 ha (5.38%) between 1997-2007 there was an increase in the use of community forest area reaching 11.94%.
– Yard: 261.4 ha (2.22%) between 1997-2007 there was an increase in land use for yards reaching 89.66%.
– State forest; 3281.7 ha (27.84), protected forest and natural tourism parks.
– Others: 1,251.9 (10.62%), critical land after the eruption of Mount Batur.