Drainage: you don’t really think about it until the floodwater creeps up on you.
The Rio Grande Valley experienced its worst flooding in modern-day history in 1967, when Hurricane Beulah hit. The Category 3 hurricane unleashed a torrential downpour that brought with it over 160-mile-per-hour winds and caused more than $1.2 billion in damages across the area.
The heavy rainfall, coupled with runoff waters from the Rio Grande watershed, overpowered the levees on the Arroyo Colorado and sent floodwaters into many residential areas, said Barry Goldsmith, warning coordination meteorologist with the National Weather Service in Brownsville.
Photographs of Beulah’s aftermath show the rooftops of homes peeking just above the surface level, with some areas taking almost two weeks to see waters recede.
The city of McAllen recently posted an image on Twitter of the flooding near the intersection of 23rd Street and Expressway 83. The street looked like a river with a few streetlights and business signs protruding just a few feet from the water.
Beulah served as a wakeup call for residents and area leaders who began envisioning a regional drainage system that would prevent such future damage from happening in the Rio Grande Valley, where the water naturally flows northeast into the bay instead of south into the Rio Grande.
The area’s topography — which is mostly flat and by no means a valley — creates a logistical dilemma to get runoff into the Laguna Madre, where it is currently being diverted with the help of a regional drainage system.
LOCAL VS FEDERAL
In 1965, two years before Beulah touched land, Hidalgo County commissioners worked with the Soil Conservation Service to conduct a drainage study to identify the area’s needs.
“Our main floodwater channel needed to be developed,” Hidalgo County Drainage District No. 1 Director Raul Sesin said.
After the 1967 hurricane, commissioners looked to the U.S. Army Corps of Engineers for help.
Commissioners held a public meeting with the federal agency and asked the leaders there to consider using the CSC study for guidance, but the Corps refused to use it, indicating the agency had to conduct its own study.
It would take about five years to conduct the new study, the Corps told the county, and then another two years to complete the design work.
“So you’re looking at like seven years before you can even start going to Congress for money,” Sesin explained.
Instead of waiting for the federal government, the county hired two local engineering firms, passed a bond issuance and developed a master plan that would take water from the county through a main floodwater channel into Willacy County before being released into the Laguna Madre.
There was only one problem. The main floodwater channel was designed to cut through part of the El Sauz Ranch in Willacy County and the owners didn’t initially agree with it.
The ranch was founded in 1792 and encompassed more than 584,000 acres. There was no way of getting to the Laguna Madre without going through the ranch.
“The El Sauz Ranch wasn’t receptive until their operation changed from ranching to agriculture,” Sesin said. “A lot of farmers cleared the land during that period and they were given three years of free rent.”
The dispute between the ranch and the county would last about four years. In 1980 both entities finally reached an agreement and began acquiring the right of way to begin constructing the current system, which takes water from cities in Hidalgo County, funnels it into county outfalls and then sends it through the main floodwater channel before being released into the bay.
The master plan called for the construction of about 200 miles worth of drainage and cost upward of $58 million, Sesin said.
ROOM FOR IMPROVEMENT
The county’s master plan was designed with a nine-and-a-half-year agricultural runoff in mind, which left ample room for improvement.
In the years following the completion of the regional drainage system, which occurred in the late 1980s, Hidalgo County has added about 100 more miles of drainage infrastructure to support rapid urbanization and its growing needs.
Hurricane Dolly and other rain events have since tested the system and pinpointed its weaknesses.
“Every storm that hits us, we’re always learning something new,” Hidalgo County Precinct 4 Commissioner Joseph Palacios said.
Many of the affected communities are located in the rural areas in Edinburg, north of Donna and other surrounding municipalities.
“That area experiences a lot of flooding because it’s very flat and everything flows east to Precinct 1,” Sesin said.
The county’s drainage district director is working on a monumental project to expand the system’s capacity through the construction of new ditches, the expansion of ones already in place and thorough interlocal agreements with other entities.
His crews have begun widening nearly 30 miles of existing ditches, increasing their capacity by 70 percent. Current and future plans will be designed with a 25-year event in mind, he said, but the whole endeavor could take upwards of 20 years.
“We haven’t done this type of work — the magnitude — ever,” Sesin said, adding most of the work is being done in-house.
Events are measured based on the probability and intensity of each storm.
A 10-year storm has a 10 percent chance of happening, while a 25-year storm has 4 percent chance.
The flooding each brings is based on various factors, including the intensity of the storm, duration of the storm, size of the drainage area and soil conditions. The Rio Grande Valley tends to have a clay-like soil that is great for agriculture, but is not very permeable.
Events are usually measured based on the amount of rainfall over a period of time.
A 25-year storm will shed about 3.40 inches of rain every hour and almost seven inches of rain per day based on the conditions of the Rio Grande Valley.
“Our system originally does not take into account the additional runoff being generated from urbanization,” Sesin said. “Hence the need for us to continue to improve our system; which we are doing.”
Dolly and her aftermath prompted an idea to expand the system through partnerships with the irrigation districts, whose main purpose is to send water into agricultural fields.
Irrigation districts are not usually in the business of drainage, but farmers also need to clear excess water from their land as fast as possible, so irrigation districts usually build ditches alongside their pipes.
During Dolly, these ditches carried a lot of water, but many of them did not have proper outfalls, which sent water from those ditches into surrounding low-lying communities, causing major flooding as a result.
Oscar Garza, then commissioner for Precinct 4, had the idea to work with irrigation districts to improve the ditches and provide adequate outfalls. He went a step further and suggested the work be handled in-house.
“The visionary behind that was Commissioner Garza,” Sesin said. “He was instrumental in the engineering and in-house construction.”
Today, the county has interlocal agreements with various irrigation districts to maintain and upgrade about 150 miles worth of ditches and to make sure they have a proper outfall.
The new connections between the county and the irrigation district have benefited 12 different subdivisions in Precinct 4, or about 6,000 people, Palacios said.
NEW ERA
Sesin, who just completed his second year at the helm of the district, is the first licensed engineer that has ever headed the department.
He’s developed an in-house approach that is bearing the brunt of the work, saving the county money and time, Palacios said.
“We have a whole in-house engineering team,” Sesin said. “We have our own surveying teams that gather data out in the field so we can use it for designs, which was never done in the district before. So in the last two years we focused on a lot of that stuff.”
Before leading the district, Sesin served as the planning administrator for the county and has been employed with the county since 1998.
“I had a real good feel because, working at the (county) I saw a lot of the issues that we had,” he said. “So I focused on areas that experienced a lot of flooding or had issues during heavy events.”
Sesin took over after the former director Godfrey Garza stepped down. The county and Godfrey Garza had a major falling out because the former director made millions of dollars in commission fees from the construction of the border wall levee system, which the county argues he had no right to do. The county is currently moving forward with a lawsuit against the former district manager, who was hired as a contractor to lead the district and was not a county employee.
Sesin, a salaried employee, said he can’t speak for the work Garza did while he was at the helm, but said his staff has noticed a shift in management styles.
“I feel good about the direction that we’re going,” he said. “I have faith and trust in my staff to continue doing what we’re doing.”
And that includes the construction of the Raymondville Drain — a project more than 20 years in the making — that will improve drainage in the northwest side of the county by channeling it across northern Willacy County and into the bay.
“Drainage infrastructure will always remain one of our highest priorities being that our county continues to grow at astronomical rates,” Palacios said. “If we can’t preserve our constituents’ personal property, then we’re adversely affecting the county as a whole.”
