Houston struggles with floods, outages, as the rain keeps falling


From the August 29, 2017 issue of Public Power Daily

Originally published August 28, 2017

 

By Jeannine Anderson
News Editor

Electric utility crews, including those at public power utilities, have been at the ready over the last few days to help with the disaster unfolding in Houston, but so far, the situation in the biggest city in Texas looks more like a matter of saving lives than of getting power restored. Texas Gov. Greg Abbott said Monday that he had activated the entire Texas National Guard of 12,000 to help with the severe flooding caused by Hurricane Harvey.

As of Monday, Aug. 28, 2,000 or more people had already been rescued from floodwaters, and it was expected that many thousands more would be forced to seek shelter. Both of Houston’s airports were closed, as were roads, schools and hospitals. President Trump is scheduled to visit the region on Tuesday. Over the weekend, at least 18 counties in Texas were declared a federal disaster area.

Brock Long, head of the Federal Emergency Management Agency, said on Monday that he expected more than 30,000 people to need emergency shelters. People who own boats or high-water vehicles were asked to help with rescue efforts.

On Sunday morning, Aug. 27, Houston Mayor Sylvester Turner said that “most major thoroughfares and their feeder roads” were impassible.

Hurricane Harvey made landfall at Corpus Christi, Texas, on Friday, with high winds and pounding rain, then became a tropical storm over the weekend. But it refused to move away, and the relentless rain has already set records and driven many people from their homes. Roads turned into canals.

Roughly 300,000 electricity customers were out of power in the Houston area on Monday. Those outages were mostly in the service territories of CenterPoint, an investor-owned utility based in Houston, and Texas AEP.  A number of rural electric cooperatives also had outages. In many cases, the outages were in homes that were flooded, and officials said that power could not be restored until the floodwaters subsided.

“Restoration efforts cannot begin until weather conditions are safe and high rainfall total and flooding could extend restoration times in many affected areas,” the Department of Energy said in an Aug. 26 briefing on the aftermath of Hurricane Harvey. “Before equipment in flooded areas can be reenergized, waters will need to recede and equipment at substations will need to dry out and be inspected for damage.”

The Electric Reliability Council of Texas late in the day Aug. 28 said that the ERCOT grid continues to be in stable condition following Hurricane Harvey. However, several transmission lines remain out of service, especially near Corpus Christi and Victoria where Hurricane Harvey made landfall, the grid operator said on a webpage that provides updates on the hurricane and its impact on the grid.

ERCOT reported that two major 345-kV transmission lines serving the Gulf Coast area were still out of service, along with many other high-voltage transmission lines. As of mid-day Aug. 28, a little more than 6,700 megawatts of generation capacity, including a very small percentage of renewables, were offline for reasons related to the storm.

Electricity demand in the days since landfall has been about 20,000 MW below typical August electricity use, peaking at less than 44,000 MW, due to a combination of structural damage along the coast and cooler temperatures in much of the region, the grid operator said.

"ERCOT operations will continue to focus on overall grid reliability during the restoration process, while transmission and distribution providers make repairs to power lines and electrical equipment. Additional engineers have been on site around the clock throughout the hurricane and tropical storm to support these operations and stay in constant communication with transmission and generation suppliers," ERCOT went on to say.

It said that system restoration times will vary depending on the extent of damage and location of the outage, as well as weather conditions in the coming days.

Public power utilities finish restoring power

For the most part, public power utilities were spared the full impact of Hurricane Harvey, said Walt Baum, executive director of the Texas Public Power Association, in an Aug. 28 interview with the American Public Power Association. TPPA is based in Austin, Texas.

Robstown, a city-owned utility that was in the storm’s direct path, was hit by strong winds, but had 95 percent of its customers back by Sunday evening, Baum said. The City of Cuero, which serves about 3,500 meters, had lost 1,000 of its customers because of the storm, but by Monday had pared that number down to 300, he said.

CPS Energy of San Antonio had 35,000 outages over the weekend, and had restored power to everyone by Monday, Baum said. Austin Energy had about 25,000 outages, and was still working to restore power to roughly 4,000, he said.

“We’ve been very impressed with the outreach from APPA, and from municipal systems throughout the country,” who have expressed eagerness to help their fellow utilities, Baum said. As of Monday afternoon, there was no need for mutual aid crews, he said.

APPA’s Mutual Aid Program was activated on Friday, said Mike Hyland, the Association's senior vice president for engineering services.

“The response from the national public power mutual aid network is amazing," Hyland said. "We hold daily calls with the affected utilities inside the Harvey footprint, and we use that information to inform our federal partners" at the Department of Energy, Department of Homeland Security and FEMA, he said.

"Having this ‘boots on the ground’ understanding of the issues facing our members in the impacted area is critical to the Mutual Aid Program success.”

Weather service: ‘all impacts unknown’

The National Weather Service said that 30 inches of rain or more had fallen already in some places in the Houston area, and that another 20 inches of rain or more could be on the way over the next few days, for a potential total of 50 inches.

“This event is unprecedented & all impacts are unknown and beyond anything experienced,” the weather service said in a tweet.

We are seeing catastrophic flooding, and this will likely expand and it will likely persist as it’s slow to recede,” Louis W. Uccellini, the NWS director, said Monday morning.

“You could not draw this forecast up,” FEMA chief Long said at the briefing. “You could not dream this forecast up.”

Houston residents were asked not to call the overburdened 911 number unless they either needed immediate medical attention or needed to be evacuated. They also were urged not to take refuge in attics, if flood waters rose, but rather to go to their rooftops where they could be seen. Chopping a hole in the roof with an axe became a safety measure.

“When escaping flood waters in your home DO NOT get trapped in your attic,” the National Weather Service tweeted. “Get on the roof and call 911.”

The Army Corps of Engineers began releasing water from two reservoirs west of Houston because the dams were under too much pressure.

“A flood of this magnitude is an 800-year event and it exceeds the design specifications of our levees,” said County Judge Robert Hebert.

NERC: Bulk power system ‘stable’

The North American Electric Reliability Council, or NERC, issued a statement on Aug. 28 saying that although there have been “some generation and transmission outages, the bulk power system has remained stable throughout this devastating, long-lasting storm.”

“We recognize that distribution systems in southeast Texas have been greatly impacted and utilities are coordinating with federal officials to restore power when and where possible, as ongoing rain and flooding creates a hazardous restoration environment,” NERC said. “Ensuring safety is a top priority as crews work to assess damage and restore power as quickly and safely as possible.”

NERC noted that the Department of Energy is issuing situation reports based on restoration activities that can be found on the Office of Electricity Delivery and Energy Reliability webpage.

Worries about flooding in Louisiana

In Texas and in Louisiana, those living near rivers kept a nervous eye on rainfall forecasts and river levels. On Monday, President Trump declared “emergency conditions” in Louisiana.

“Flooding is the major concern,” said Greg Labbe, transmission and distribution operations supervisor for the Lafayette Utility System in Lafayette, Louisiana, in an Aug. 28 interview with the American Public Power Association.

As of midday on Monday, LUS has had only a few outages, Labbe said.

“We’ve been lucky so far,” he said.

 

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