The swath of destruction read like a message scrawled across the city of Galveston, Texas: Ike was here.

Aerial footage shows homes ripped from their foundations, animals seeking refuge on what's left of raised porches and boats floating listlessly on their sides in the ocean.

Idyllic seaside towns across the south-eastern coast of the state, such as Galveston, were left half-submerged in water after the hurricane hit on Saturday and officials can't speculate when levels will recede.

Officials have told all residents to stay away from Galveston, as they predict it could take up to a month to restore power and that roads are still flooded.

For those that did stay, many had to be rescued on Sunday after ignoring a mandatory evacuation order.

Search teams rescued nearly 2,000 people in the wake of hurricane Ike on Sunday.

At a news conference Sunday afternoon, authorities said 1,984 people had been rescued so far, including 394 by air.

Crews began the door-to-door ground search -- the state's largest rescue operation in history -- for trapped residents on Sunday.

Search teams were looking for residents who may have been stuck in the upper floors or attics in their homes because of high flood waters.

"It's really an army of rescue folks that are along the coast, all the way up to Louisiana," Glenn Cannon, of the Federal Emergency Management Agency (FEMA) disaster operations, told CTV Newsnet Sunday.

"So today's activity is kind of the more intensive grid-by-grid, door-to-door search of affected properties, those that are still isolated and those that have been obviously flooded. But I think we'll be in good shape by the end of today."

Many of those who have been rescued have been healthy and uninjured, Cannon said.

However, there have been four hurricane-related deaths reported so far and officials believe that number will climb.

The city, worried about residents' safety, has announced a curfew that will last until Saturday. Residents are not allowed on the streets between 9 p.m. and 6 a.m. except in emergency situations.

In Houston, skyscrapers' windows were shattered and roads were strewn with downed trees and debris.

Efforts are underway to restore water pressure and electricity to the hundreds of thousands of residents who are without power.

Electricity has been restored to one Houston medical centre and to the water pumping stations, Mayor Bill White told reporters Sunday.

However, more than one million residents are still without electricity. White has asked officials from the private company that owns and operates the power lines to make quick work of power restoration.

"We have emphasized to them the fact that everything humanly possible should be done to get our electrical power grid in this area back up as soon as possible," White said.

He asked residents to be patient because it's work that "can't be done in a day. If you see all the downed power lines you'll understand what I'm talking about."

Residents are also urged to take precautions with the water supply.

"We have no evidence that there's been any contamination of the water," White said. "But we are legally required to ask residents to use bottled water, to boil water, take precautions and to continue to conserve water until we are sure that our water supply is safe and tested as the law requires it to be."

Energy hub takes a hit

Hurricane Ike tore apart at least 10 oil production platforms and damaged some pipelines in the Gulf of Mexico, U.S. officials said Sunday.

Lars Herbst, regional director for the U.S. Minerals Management Service, told the Associated Press that flyovers show the area was hit harder than when Gustav struck two weeks ago.

There is no word yet on how big the destroyed platforms were or how much oil production in the Gulf of Mexico will be affected.

There are about 3,800 production platforms in the Gulf and just about 100 per cent of crude production in the region has stopped since just before Gustav's arrival two weeks ago.

Approximately 98 per cent of natural gas production is also on hold.

As crews survey the damage left behind by Ike, it appears the eye of the storm missed many of the region's key refineries and chemical plants, which are located near Houston.

Had the storm hit those areas more directly, "the economic costs could have been much greater," said Chris Johnson, a commercial property insurer.

"If the eye of that storm had been as much as 30 kilometres east, we would have a lot more havoc and damage than we did," he told The Associated Press. Nevertheless, more than half of the refineries in Texas remain closed because of Ike.

Herbst said it was too early to tell if they were approaching the damage levels seen three years ago when both hurricane Katrina and Rita hit.

In 2005, hurricane Katrina destroyed 44 platforms while hurricane Rita destroyed 64 quickly after that. Both storms damaged about 150 pipelines that gather and transport oil and natural gas from offshore wells.

Ike moves north

According to the U.S. National Hurricane Center, Ike was 65 kilometres west of Toledo, Ohio at 5 p.m. ET on Sunday. It was categorized as a tropical depression as its winds slowed down to less than 60 km/h.

The storm is expected to bring some rain and wind to parts of Central and Atlantic Canada. Environment Canada said the Greater Toronto Area will be hit with about 30 millimetres of rain Sunday.

Ike left billions in damage after it left the Caribbean earlier in the week. It also claimed at least 80 lives in the region, mostly in Haiti. In Cuba, Ike tore down aging buildings and devastated tobacco crops on the western coast of Havana.

About 2.6 million people -- about a fifth of Cuba's population -- fled from the storm, leaving communities and seaside towns.

With files from The Associated Press