Reprint from the Progress Times - June 15, 2007
©Progress Times 2007 - All Rights Reserved

County: Buy Flood Insurance Now Before FEMA Re-Draws Flood Maps

By Kathy Olivarez

“Hidalgo County residents who live in the new flood zones that are to go into effect in September should buy flood insurance now,” Godfrey Garza, Hidalgo County Drainage District Manager and Flood Plain Administrator told the Progress Times in an interview held Wednesday, June 13.

“If they do, they will pay a minimum rate and be grandfathered in at that rate when the new flood zone maps are issued in September. Rates for flood insurance for those living in those areas will skyrocket when the maps become official.”

The area Garza is referring to is basically anything south of Expressway 83. Over thousands of years the Rio Grande has moved steadily southward. At one time the riverbank was located where Expressway 83 now stands. It was built along a natural ridge that was once the old riverbank.

Should there be a catastrophic flooding event where the levees did not hold and the river overflowed, the water could flow over the banks as far north as the expressway. According to Garza the way floodwaters flow in the Valley is that anything south of Expressway 83 would move toward the Rio Grande River. Anything north of the expressway would move northeast toward the Laguna Madre through Willacy County.

Garza said areas that would be vulnerable to flooding would include everything in Hunt Valley Development, Cimarron, Seven Oaks and Tierra Dorada on Scheubach Road in Mission. It would include Balboa Acres (with an estimated population of 20,000 people) and the area of the McAllen Airport. Estimates say the airport could be under as much as 10 feet of water.

FEMA will bring new flood plain maps out in September, which show all of these areas are now in potential flood zones. There are several reasons for this change. They are currently conducting hydrologic tests to determine just how deeply underwater the area would be.

The first is the result of a lawsuit between the International Boundary Water Commission and the U.S. Fish & Wildlife over the amount of brush that will be allowed to exist in the floodplain. The brush provides food and habitat for the wildlife that lives along the river. However, Garza said that the more brush allowed in the floodbasin, the higher water will rise in a time of flood.

A second factor comes from knowledge gained after the horrific flooding of New Orleans after Hurricane Katrina. A one-foot freeboard for levees was considered to be a normal safety factor for the levees built in this country built in the 1940s and 1950s. The term means that the levees were built one foot higher than the highest level that floodwaters had ever reached in the area.

The one-foot freeboard levees were insufficient to hold the water generated by Hurricane Katrina. The new standard is now three feet. In some instances even a freeboard of four to five feet might be considered too low.

Garza said the flood factors are based upon the volume of water not a storm. In fact, the Valley could be “bone dry without a drop of water” and still flood if a storm pours water into the river's drainage basin. It could happen anywhere along the river's course from El Paso to the mouth of the river. Even if the storm does not hit the river directly and instead dumps volumes of water into one of the rivers that feeds into the Rio Grande the potential for flooding is there.

One likely scenario for the Valley would be like the case of Hurricane Gilbert that went over Monterrey and caused tremendous flooding and death when the river flooded. Eventually that water made its way down the Mexican river that feeds into the Rio Grande north of Falcon Dam. Because the water in the dam was so low at the time it refilled it and water was released into the riverbed. But fortunately there was no flooding that the levees could not handle.

Garza said it depends on the volume of water. He brought up Hurricane Beulah, the storm that hit the Valley directly 40 years ago. While it was rated a level three storm because of wind, the storm was a torrential rainstorm that created a 130-year storm scenario.

It was decided in the 1950s to build Falcon Dam to provide for flood control, a source of irrigation and to provide power for the Rio Grande Valley. It was just an act of luck that the dam was nearly completed just shortly before Hurricane Beulah hit. It had been predicted that it would take five years to fill the dam. The floodwaters from Hurricane Beulah filled the dam to capacity. Had the dam not been in place the Rio Grande Valley would have been severely flooded.

FEMA's new maps are expected to include large areas of the Rio Grande Valley in the floodplain. Elevations vary across the city with a difference of 75 feet in elevation from the river to the highest point in north Mission. The land continues to rise to the northwest with McCook being 150 feet above the level of the river. But most of the land to the east lies below what FEMA considers to be a flood zone. Garza said most of the land east of Stewart Road all the way to Raymondville will be in the new flood zone.

Garza said things have changed since the 1960s. Most of the area in question was used for agricultural purposes at that time. Today, the area is much more urbanized. This is a major factor in the redesigning of Valley flood maps by FEMA.

After Hurricane Beulah, a closure at Anzalduas Dam was built to close the old flood system, which is now considered to be four to five feet too low. Water was redirected into the Arroyo Colorado floodway, developed south of the old floodway, closer to the river. However, after looking at what happened to New Orleans after Hurricane Katrina, it has been determined that certain areas of the current levee system might not be adequate to meet the need. A nine-mile stretch from Penitas to Anzaldaus Dam needs immediate repairs, which Garza estimates would cost $28 million.

However repairing just this area will not solve the problem. If other levees in the system remain lower, the water will just flow around the repaired levees to fill the flood basin. To repair the levees in all of Hidalgo County would cost an estimated $80 million. Garza said Cameron County would also have to address their flood problems if the situation is to be completely resolved.

Garza was among a group of Hidalgo County officials including Judge J.D. Salinas who recently went to Washington, D.C. to ask for money to repair the levees. While they were promised $2-$3 million in federal money to help with repairs, the truth is that most federal money is going to the war in Iraq, to fight terrorism and to Homeland Security.

A bill generated in the White House calls for another $5 million to be allocated to repairs of levees along the Rio Grande River. Congressional leadership is trying to get the amount raised to $15 million.

“In reality, although repairing the levees should be done with federal money, it looks like the county is going to have to pay for it instead,” said Garza.

He pointed out that a recent $100 million bond election passed by voters had $10 million included for repair of the levee from Anzalduas Dam to the Mission Inlet, a distance of four to five miles.

“But just repairing this area will not stop the area from flooding,” sad Garza. The water will just come around the repaired levees from areas where the water is lower. We may have to rethink the way we are going to allocate this money and spend more of it on repairing the levees.”

Currently, the cities do not have the money needed to build the levees. They will have to rely on the drainage district to come up with a solution. What cities do have is a plan to relocate people from the south part of Mission to north Mission in case of a flood threat.

“People need to understand that even if the Valley is bone dry when the warning is given, they need to evacuate before the water comes. The water that could flood the Valley may be coming from El Paso or some other spot along the Rio Grande, or from one of the feeder rivers in Mexico,” said Garza.

Hidalgo County officials along with Garza are working to find a solution to the problem that will stave off the new flood zone insurance rates that will go into effect. They hope that some kind of temporary agreement can be reached that will keep most of Hidalgo County and the Rio Grande Valley out of the proposed flood zone. But there are no guarantees this will happen. Those who want to be on the safe side should look into purchasing flood insurance now.