* Peru to auction reconstruction contracts in August or September
* Damaged minerals railway to take two weeks to become operative
* Donations in Peru tapering off, local El Nino expected until May
* Local economists have put cost of rebuilding at $6 billion
By Mitra Taj and Marco Aquino
LIMA, March 31 (Reuters) - Peru needs more international aid to help hundreds of thousands of people cope with continuing floods and mudslides that have killed more than 100 people and torn apart much of the country's infrastructure, the transportation minister said Friday.
Minister Martin Vizcarra told Reuters that the government will likely award reconstruction contracts in August or September, once heavy rains and the current crisis have subsided.
Peruvians displaced by raging rivers and landslides still need bottled water, canned food, tents, toilet paper, medicine and other basics to survive coming months, Vizcarra said.
Peru has distributed 4,000 tonnes of aid so far, most of it donated by Peruvian families and companies and institutions, but another 4,000 tonnes will likely be needed in coming months, Vizcarra said.
Local donations were tapering off as raging rivers and mudslides continue to slam parts of Peru.
"Every family, company has a limit to what it can give," Vizcarra told Reuters in an interview. "But people are going to be in need for a long time. There are families that have nothing."
He noted that Peru prefers goods that could be distributed immediately to cash donations.
A railway used to transport zinc and copper concentrates from mines in central Peru to port will likely take another two weeks to become operative, Vizcarra said.
The government will likely hold public tenders for "packets" of projects - such as bridges needed in a region - to ensure a swift recovery.
So far, more than 200 bridges and more than 2,000 kilometers of highway have been wiped out, Vizcarra said. Scientists in Peru now expect the localized version of El Nino that appeared suddenly off of Peru's coast this year to stretch into May, though April rains should not be as intense as the downpours still battering the northern coast.
The United States said Thursday that it had allocated more than $775,000 to help Peru, about half of China's donation of $1.5 million to the Andean country.
Economists in Peru have put the cost of reconstruction at more than $6 billion - more than 3 percent of gross domestic product.
(Reporting By Mitra Taj and Marco Aquino; Editing by Eric Meijer)