According to Dwi, based on data from the University of Lambung Mangkurat (ULM) Banjarmasin, now the intrusion of seawater into the mainland has reached 60-70 kilometers.
That means, he added, the natural conditions of South Kalimantan have been very alarming that it needs effort from all parties to immediately recover the existing environmental conditions.
"At the seminar, ULM delivered data that the intrusion of seawater to the mainland is much worse than 10 years ago," he said in Banjarmasin on Thursday.
The intrusion of saltwater is the movement of saltwater into freshwater aquifers that can contaminate drinking water sources. Intrusion can occur naturally to a certain degree in most coastal aquifers, due to hydraulic connections between groundwater and seawater.
The more severe the intrusion of seawater to the land during the dry season will cause the river water in some areas in South Kalimantan to become brackish and cannot be consumed.
Overcoming it, he added, it is necessary efforts of all parties concerned to restore environmental conditions with a lot of planting trees, especially on critical land.
In addition, he added, it needs the government's commitment to preserve the environment by not easy to grant mining and other licenses to water storage areas.
If the water storage area should be used for other purposes, he added, efforts should be made that would not damage the environment and disrupt the water storage function.
"Currently, we must really be able to use nature for water availability, nature must be fully guarded," he said.
Another effort to maintain water conditions, especially during the dry season, is with the construction of dams.