The Nam Ngum 1 heavily influences local agriculture irrigation. According to the 2005 national census, subsistence-based agriculture is the main form of livelihood generation for the majority of citizens, and 75 percent of the population in basin provinces report agriculture as their primary form of employment. Some government officials and academics have raised concerns about if the water required for hydropower generation could co-exist with the water being used for irrigation expansion. A study from Duke recently used the Nam Ngum dam as a case study to model the effects of current and expanded hydropower usage on the river. The study determined that if high-levels of water availability continue tradeoffs between agricultural and hydropower goals will be modest because with high-levels of water irrigation expansion will not significantly effect hydropower generation or vice versa. However, the study did find that under dry conditions the tradeoff between expanded irrigation and hydropower increases. The study determined that continued hydropower generation and hydropower expansion could become exceedingly difficult in such conditions. This is because future returns from Nam Ngum dam and expanded agriculture are largely dependent on high levels of rainfall and water levels. Accordingly, the expected future economic returns from the Nam Ngum dam as well as agriculture expansion in the Vientiane province would be severely decreased in dry conditions. As a result of the potential impact of dry conditions, there is widespread uncertainty about the future of Nam Ngum 1 and further hydropower project on the Nam Ngum. Some scholars have become concerned that climate change may lead to decreased levels of rainfall. As with fishing in the reservoir, the government of the Lao PDR will likely have to take steps to address hydrology issues in the future.