To enter the park, first you must cross the Dong Nai river ... Nam Cat Tien is protected on two sides by the river - which makes an unabiguous boundary against forest clearance.
Denuded hills on opposite bank
The river level varies by more than 6 metres in some parts - especially near the park HQ ...
The same stretch of river during the dry                                  ... and rainy seasons        Managing for the rainy season water levels:
Raised walkway near the 'crocodile lake', which floods extensively during the rainy season	Ford on the park road: dry for much of the year, this is crucial for forest drainage during the rainy season
	There is an increasing awareness amongst policy makers of the various services that forests perform: including absorbing carbon dioxide and providing clean water. Denuded slopes on river banks result in soil erosion, which not only causes rapid loss of fertility for the land in question, but also loads mud (and possibly agricultural chemicals) into rivers. This is illustrated well in the picture here, which shows the confluence of clean creek water, originating from Park forest, with muddy water from the Dong Nai river. This leads downstream into the Tri An reservoir: the main water supply for Ho Chi Minh City.