The record-setting floodwaters in Houston rose again as the remnants of Harvey remained on Monday, hovering over the fourth largest city as the downpour persisted and residents battled sinkholes, high water and growing frustration.

Even as a Tropical Storm, Harvey has been relentless, producing 30 inches of rain, a Herculean amount which was unfathomable, even to meteorologists. While it was downgraded from a Category 4 hurricane, the storm still has thrust thousands of people onto roadways and rooftops to be rescued by government and civilian boats and helicopters as others evacuated to higher grounds.

The Federal Emergency Management Agency said it estimates at least 450,000 people will need to seek federal aid as 30,000 people will seek help in shelters. Even as the death toll rose to ten people throughout the state, Harvey planned a return as it returned back to the Gulf of Mexico and is estimated to return to far eastern Texas and southwest Louisiana.

The worst case scenario is that Houston has not seen the last of Harvey and could generate even more damage than what it has already inflicted. In just three days, the destruction includes streets collapsing and an explosion which started a fire in downtown Houston on Monday at the Lone Star Legal Aid, a blaze that took four hours to distinguish.

Dramatic rescues occurred on Sunday as rescuers in helicopters plucked elderly and ill Houstonians off the rooftops of homes and apartment buildings while the Coast Guard and volunteers, including a 15-year old named Declan and his friends picked up strangers in their boat. A convoy from Louisiana, the "Cajun Navy," appeared on Sunday with their boats to come to the aid of their neighbors. One truck driver in an 18-wheeler was saved when a reporter from Houston's KHOU TV channel saw his predicament and flagged down the police.

Even more precarious situations could occur in the coming days as the National Hurricane Center is predicting that the catastrophic and "life-threatening" flooding will not be halted in southeastern Texas and anticipates another 15 to 25 inches. The deluge is spreading to southwestern Louisiana which is also expected to also receive 15 to 25 inches.

The unprecedented flooding could produce even more dire situations such as electrical fires, refinery explosions and underground storage tanks of gasoline floating.

Hurricane Harvey.
Hurricane Harvey.

"Refineries can experience flooding, power loss, fires and explosions," said Patrick DeHaan, a senior petroleum analyst for GasBuddy.com, a Boston-based provider of retail fuel pricing information and data. "Any unpredictable event that disrupts the delicate balance of supply and demand usually leads to higher gas prices."

The refining capacity in Texas has been decreased by 2.2 million of barrels of oil a day while the major ports in Corpus Christi and Houston were also closed.

Another major concern is whether the underground storage tanks in Houston are flooded or if they break out of the underground layer that they were installed in and become buoyant, said DeHaan. Across the U.S., there are 230 million barrels of gasoline or the equivalent of 20 days in storage.

"There are about 40 million barrels oil in Houston which are used in products such as gasoline and jet fuel," he said. "We will have to see how those tanks are holding up to flood water."

There have not been any reports of spills or damages to storage tanks in Corpus Christi, according to S&P Global Platts.

There are also concerns about the damage done to the Colonial Pipeline, which is a major distributor of gasoline, diesel and jet fuel and starts in Houston, runs through Louisiana and picks up products, then moves to Mississippi, Alabama, Georgia, up to the Carolinas and to Virginia.

"If it is not collecting gasoline from the refineries, it could be a real problem for other states," DeHaan said.

Late Sunday, the U.S. Army Corps of Engineers released water from two Houston-area reservoirs, the Addicks and Barker into Buffalo Bayou, the primary body of water running through the city. The planned release is intended to prevent water from flowing uncontrollably from the dams, but will flood surrounding homes.

If this tactic does not alleviate the rising water, the dams could fail to hold their existing levels of water and flood into downtown Houston, which is already inundated with massive rainfall. This could turn the already catastrophic flooding into an even more stupendous scenario as the city faces colossal damages with federal aid expected for several years to come.

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