The urban forest in Telagasari, which was inaugurated in 1996 with an area of , has now shrunk to just around . The forest in the middle of this city has been surrounded by residential areas. The protected forest of the Manggar River also suffered considerable damage, which is around 60%. The reservoirs in this forest are also threatened because coal mining fields and brick mills were set up so close that there was siltation of reservoir water. The majority of those who founded it were even known to be immigrant communities. In addition, the construction of the Samarinda-Balikpapan toll road planned by the East Kalimantan government which divides the forest for 8 kilometers across the reservoir could damage the quality of the clean water reserve in Balikpapan.