By Dagny Carlsson, For The Leader
At 3 a.m. on a stormy August night in 2017, the Bilderback family remained awake and alert. The rain dumped by Hurricane Harvey was rising quickly to their doorstep on Del Norte Street, forcing the family to bail the water from their front porch. The water was seeping through the sandbag barrier created to protect their front door, and the family was doing all they could to prevent it from entering the house.
They’d flooded before. In 2008, during the heavy rains that followed Hurricane Ike, Glen Bilderback woke up to 3 inches of water in his home as well as plugged-up bar ditches and overloaded culverts.
Less than a decade later, while the Bilderbacks worked for hours to prevent water from devastating their home for the second time, their neighbors on Lehman Street one block to the south slept soundly. Flooding risks had been mitigated on part of the latter street in 2011, when the City of Houston did work to address the issue.
The threat of flooding is still a concern for the Bilderbacks when major rain events, such as the steady downpour this week caused by Tropical Storm Beta, hit Houston.
“I can’t believe our problems haven’t been solved,” Bilderback said. “I’d thought when the city made improvements, it would have helped the entire neighborhood. Yet our house nearly flooded again (in 2017).”
The problem the Bilderback family faces is not new in Ella Lee Forest, a small, oval-shaped subdivision south of Pinemont Drive and west of Ella Boulevard. In October 2008, Kent Varner, a Lehman Street resident who then was president of the homeowners association, reached out to the city to address the flooding that Ella Lee Forest had experienced during Hurricane Ike.
He contacted the city repeatedly over the next two-and-a-half years, and in June 2011, the city published a drainage report that identified the neighborhood’s issues and suggested possible solutions that could be implemented.
“It took us three years to get them out there,” Varner said. “It usually takes around that time. They have to assemble their team of engineers, so it takes a while for them to actually get digging.”
Later in 2011, the city upgraded dozens of culverts along the neighborhood’s main drainage route, which dumps water in a tributary just outside the neighborhood. The corresponding outfall pipes running along Oak Forest Drive, one of four cross streets connecting Del Norte to the north and Lehman to the south, also were enlarged.
However, as the Bilderbacks can attest, the improvements after Ike in 2008 have not been noticeable to everyone in the neighborhood. In fact, the drainage report stated that the suggested changes “are not expected to prevent structural flooding,” and that the upgrades would “only improve the overall drainage conditions throughout the project area west of Oak Forest Drive,” leaving around two-thirds of the neighborhood without improvement.
With hurricane season in full swing, the pressure is on for these problems to be addressed before more damage is inflicted. Residents have suggested several theories on how Ella Lee Forest’s flooding issues can be addressed.
The first of the possible solutions deals with the continued enlargement of round, mostly concrete culverts that run underneath driveways throughout the neighborhood. Due to the neighborhood’s bar ditch system, culverts are integral to the task of moving water out of the neighborhood.
According to infrastructure data from Houston Public Works, obtained through an open records request, most of the driveway culverts in the neighborhood are 18 inches in diameter. On Del Norte, which drains to Lehman, 16 culverts are smaller than that and only two are wider.
Lehman has 10 culverts that are 22 or 24 inches in diameter. Most of the culverts on Oak Forest Drive and Maxroy Street, the two cross streets in the middle part of the subdivision, are least 24 inches wide.
“The (Harris County) Flood Control District doesn’t even allow pipes smaller than 24 inches anymore,” said Matt Zeve, director of operations at the flood control district. “A big part of the challenges that we face at the flood control district is retrofitting infrastructure that was put in place 40, 50, 60 years ago.”
Culverts a culprit?
Varner agreed that, despite the 2011 enlargement of the culverts in accordance with the recommendations put forth by the drainage report, culvert size in Ella Lee Forest remains an issue. He, along with several of his fellow neighbors, has encouraged Ella Lee residents to upgrade to 30-inch culverts when possible.
“We have 18-inch driveway culverts that feed into 42-inch outfall pipes,” Varner said. “To some extent, the pressure is on the individual homeowner to upgrade their culverts when they get a chance. Our goal is to have all new builds move more water.”
The drainage report identified a second potential threat in the form of silt buildup. In response, the flood control district initiated maintenance efforts to restore the neighboring tributary to its original condition. In 2019, it completed a de-silt of the ditch next to Ella Lee Forest, only six days before the rains from Tropical Storm Imelda struck Houston and brought widespread flooding, including in the neighborhood.
De-silting efforts also took place within the neighborhood. Some ditches in Ella Lee Forest were dug out by the city this June.
Still, de-silting efforts only provide temporary relief, and haven’t been enough to fully address flooding in the past. This could be an issue with how the neighborhood is designed to channel water: The neighborhood’s system is meant to allow water to flow from Del Norte to Lehman and from Lehman out to White Oak Bayou’s tributaries.
Yet, the 2011 report noted there are limited drainage points from Del Norte’s ditches to Lehman’s. Residents believe that while the later expansions of outfall pipes helped to alleviate some of the problem, inadequate culverts connecting Del Norte to Lehman kept water bottled up on Del Norte, leading to flooding.
“Enlarge the culverts,” Del Norte resident Tim Middleton said. “Basically, the problem here is water needs to get out of the neighborhood faster.”
Fortunately for Ella Lee Forest residents, upcoming projects may do more to shed light on the situation and assist homeowners in their fight for improved drainage infrastructure.
“In the coming months, HCFCD is looking to partner with the City of Houston to conduct a comprehensive study of the area around Del Norte to identify antiquated infrastructure and work toward reducing flood risk,” Zeve said.
After pinpointing problem areas, the flood control district can remove bottlenecks and ensure the culverts, ditches and detention basins are up-to-date.
A larger-scale project is already underway. MAAPNext (www.maapnext.org), wherein HCFCD has partnered with FEMA to create a county floodplain map, is intended to provide a greater understanding of flood risks across the city, including previously unmapped urban flooding. The project is scheduled to release its first maps in Spring 2022. According to Zeve, Ella Lee Forest is among the first areas scheduled to be mapped.
Additionally, city regulations regarding floodplains have become much stricter since Hurricane Harvey. The new standards increased the elevation requirements for new builds by several feet.
“September 1, 2018, the city updated their floodplain regulations,” Zeve said. “They were updated again in July of 2019. Now the flood control district is working with the city to update the regulations yet again.”
As a result, Houstonians can expect new development and construction to help reduce flooding rather than contribute to it.
While the influx of new research and comprehensive mapping are sure to bring attention to neighborhoods like Ella Lee Forest, in the meantime, residents can help ensure their ditches are effective by keeping them clear of litter, debris and decoration, and ensuring their culverts are unblocked.
Most importantly, though, Zeve said, “The Harris County Flood Control District strongly recommends that everyone in Houston buy flood insurance.”
The upcoming efforts aim to address the deficiencies in Houston’s flood prevention infrastructure and ensure that the drainage system in Ella Lee Forest becomes reliable for all residents, and not just on one of its main streets.
“We need to be squeaky wheels on this issue,” Bilderback said. “Either that, or we must resign ourselves to stocking sandbags.”