( CNN ) Countries around the world have launched massive aid operations to help victims of the Nepal earthquake , but distribution of aid faces challenges as Nepal is still trying to come to terms with the scale of the disaster . With over 4,400 dead , 8,000 injured and 8 million people across Nepal affected , numerous aid groups and at least 16 nations have rushed to send supplies and workers to the stricken country . But now the Nepalese government and army who are leading the disaster response face another problem : How to effectively coordinate and organize the massive influx of humanitarian aid . Here are three major obstacles that are hampering efforts of distribution . Nepal relies on only one international airport to receive and deliver aid . Relief organizations say the tarmac at Tribhuvan International Airport remains jam-packed with a large number of cargo planes . Several aircraft carrying essential supplies have been turned away , or diverted to India and elsewhere . `` The airport is totally congested . Even the planes which have landed , goods have n't been offloaded , '' Jagan Chapagain , the Asia Pacific Director of the IFRC ( International Federations of Red Cross and Red Crescent Societies ) told CNN . Flightradar24 , a live air traffic monitor , shows that incoming flights have had to circle in the air several times before being able to land . The United Nations Disaster Assessment and Coordination ( UNDAC ) team who is on the ground coordinating international relief efforts says they are doing all they can to address the problem . `` There are lots of flights arriving from around the world for search and rescue , and that 's the challenge we 're trying to address by supporting the airport staff directly , '' said Marcus Werne , a UNDAC team leader . But Chapagain says that airport management is still chaotic , with staff and military not being able to clear runways and offload supplies effectively . According to a U.N. situation report , main roads in Kathmandu are open , but remote areas are largely inaccessible . `` Due to the mountainous geography , infrastructure damage , collapsed bridges and damaged roads , access to many of the affected areas is reported to be extremely limited , '' read the report . The Nepalese government has not been able to provide relief to all affected areas due to difficulties in transporting goods , a government official told CNN . `` The helicopters are small . They do n't fly in windy and cloudy conditions . Given Nepal 's geographical terrain we can not use surface transport much but we are using it , '' said Sagar Mani Parajuli , the Joint Secretary for Nepal 's Home Ministry . The situation has deteriorated to the point where relief workers are as good as stranded . Pirtha Raj Joshi , a disaster management officer for Nepal Red Cross , had to walk 10 hours to reach a office in one of the severely affected districts , said Chapagain . Initial reports from the IFRC say that over 36,000 houses have been totally destroyed , with the number expected to rise as teams arriving in severely affected areas continue to assess damages . Just two days after the earthquake struck , Nepalese authorities leading the response are still trying to fully understand which areas have been affected , how they are affected and what the priorities are . `` Typically what we see , also in other emergencies , is that it takes a few days for supply lines , distribution lines to stabilize , '' UNDAC 's Werne told CNN . `` Right now we 're working with a lot of secondary data , and working on some of the key vulnerable areas identified prior to the earthquake , '' he added . The operation to get aid to survivors in Nepal is still `` very ad hoc '' and it will be a few days before the distribution becomes organized because the government is still constrained by the scale of the disaster , says Chapagain . CNN 's Manesh Shrestha in Kathmandu , and Bex Wright and Jethro Mullen in Hong Kong , contributed to this report .
Nepalese authorities struggle with trying to coordinate a massive influx of international aid . Relief organizations say lots of aid supplies remain stuck in cargo aircraft on the tarmac . Damaged roads and infrastructure have hampered distribution efforts and rescue teams trying to access remote areas .