Kaeng Krachan National Park was established in 1981, the 28 th National Park in Thailand. It is the largest national park in Thailand, with 2,914.70 sq.km. of forest in the watersheds of the Phetchaburi and Pranburi rivers. It includes portions of Nong Ya Plong, and Kaeng Krachan districts in Phetchaburi Province and of Hua Hin district in Prachuap Khiri Khan Province.
His Majesty King Bhumipol Adulyadej has visited the site many times, both before and after the construction of the dam. He has always been very concerned about the conservation of this watershed area, an indicated in his speech of October 29, 1979. “ In Phetchaburi watershed forest, illegal logging or cultivation, because they cause drought.”
The National Park was designated on June 12, 1981 ; its original borders encompassed 2,478 sq.km.Later, in the park area was extended, as proposed by the Hua Hin Environmental Conservation Group, to cover the boundary between Phetchaburi and Prachuap Khiri Khan provinces.
The area, about 45 squares kilometers, consists of both ground and water in reservoir. The vastly forest upper the Kang Kra Jan Dam is on complicated mountain ranges which the highest peak is 1,200 meters above sea level and approximately high 500 meter above sea level. Most of the mountains are Granite Mountain, few are Limestone Mountains, and many are full of fluoride. And also most of the area is covered by rain forest so that is the source of Phet Buri River and Pran Buri River.
The park is compossed of two major watersheds. About half of the area drains to the Phetchaburi River, which flows to Kaeng Krachan dam at the eastern edge of the park and then down through farmland to the provincial capital of Phetchaburi. The southern haft of the park drains to the Pranburi River, which flows south to the Pranburi dam and then on to the town of Pranburi in Prachuab Khiri Khan Province. Because of abundant rainfall and undisturbed forest cover in these watersheds, the streams, waterfall and rivers of Keang Krachan flow year round.
The park is composed of two major watersheds and a large evergreen forest. About half of the area drains to Phetchaburi River, which flows to Kaeng Krachan dam and the southern half of the park drains to the Pranburi River. Humidity remains high throughout the year, with heavy rain during the rainy season and cool weather for much of the year. The steep forested areas of the park are even more humid than the young forest and cleared lands in the lower elevations.
In rainy season, the national park will be closed Ban Krang and Panoen Thung area during August and October every year for visitors safety and forest recovering.
Kaeng Krachan is located on the eastern slope of the Tenasserim Mountain Range at the border of Myanmar. It occupies the western half of Phetchaburi Province (Kaeng Krachan and Nong Ya Plong districts) and a portion of northern Prachuap Khiri Khan province (Hua Hin District).
Most of the park is covered in deep, steep forest. Over three-quarters of the area has slopes greater than 30 %, 85 % of the terrain is evergreen rainforest, another 10 % is mixed deciduous forest. The forest is rich and complex, with hanging lianas, ferns and orchids, and an abundance of fruiting trees and vines. The forest of kaeng Krachan is unusually diverse because of its location at the juncture of continental Asia and the Malaysian Peninsula. Continental species such as oaks, chestnuts, and maples are found here, as are peninsula palms and fruiting trees. Some of the valuable trees of Kaeng Krachan include makhamong (Afzelia), takhian (Hopea), chanthana (Tarena), yang (Dipterocarpus), taback (Lagerstroemia), pradu (Pterocarpus), kritsana (Aquilaria), and many more.
Like the plant community, the animals of Kaeng Krachan represent both Asiatic and Malaysian species. Over 400 species of birds are known to occur within the Park’s boundaries, and 57 mammals. Larger mammals include elephant, gaur, sambar deer, banteng, serow, and bear, indo-chinese tiger, leopard, both common and Fea’s muntjac. Malayan tapir, white-handed gibbon, dusky and banded langurs, Asian wild dog, otter, and wild boar. Among the birds recorded in the park are six species of hornbills, red junglefowl, both Kalij pheasant and grey peacock-pheasant, woolly-necked stork, black eagle, and many species of songbirds, woodpeckers and other forest birds. The ratchet-tailed treepie, first seen here by members of the Bangkok Bird Club (Bird Conservation Society of Thailand) on an outing in 1991, has not been recorded anywhere else in Thailand.