After the water purification units are up and running, officials expected 300,000 litres of water to be produced by the end of Saturday. Water also apparently was being brought in from the Dominican Republic.
U.S. troops have arrived -- 4,200 on the ground and on ships off the coast -- and thousands more are expected ashore by next week.
Despite being in Haiti for less than 24 hours, the carrier USS Carl Vinson has "contributed tremendously" in getting supplies to the airport and other landing zones, Navy Rear Adm. Victor G. Guillory told reporters in a conference call today. The 19 helicopters aboard the carrier are being used to deliver food, water and medicine.
This morning there were at least 20 sorties from the airport moving food and water to landing zones in the city near distribution nodes.
"The Navy is doing its best to flow material as quickly as possible ... getting better supplies to the people who need it," Guillory said. "I will tell you it will get better over time."
Because the port facilities at Port-au-Prince have suffered major damage, the Navy is sending the salvage ship USS Grasp, along with a complement of construction divers. The divers will see how extensive the damage is and whether some of the port facilities might be repaired. They're also looking at sending mobile piers.
American officials also are helping Haiti manage flights in and out of the damaged airport in Port-au-Prince.
In the longer term, the USNS Comfort, a floating hospital with a crew of 500 sailors, doctors and nurses, is expected to drop anchor outside Port-au-Prince this coming week, about nine days after Tuesday's earthquake.
According to the U.S. Navy, if the ship were on the ground in the United States, it would be the nation's biggest hospital. It has enough supplies and staff to treat 40,000 Haitians over the next several weeks, the ship's captain said.
Everyone on board has seen the pictures from Haiti.
"It has, at times, you know, been overwhelming emotionally," Lt. Cmd. Thomas Olivero said. "What's hard is to see everything that's going on over there and not being there. ... We will do everything we can. I mean, that's what we are going there for."
ABC News' Kate Snow, Chris Cuomo, Rachel Martin, David Kerley, Luis Martinez, Richard Besser and Christine Romo contributed to this report.