Unmanned Aircraft Systems and the HCFCD
The Harris County Flood Control District is testing the use of small, unmanned, remotely guided aircraft as a cost-effective tool for conducting flood control project surveys, and for collecting maintenance-related data and imagery.
The Flood Control District joins a wide range of government agencies – from public works and parks departments to the U.S. Army Corps of Engineers – who use unmanned aircraft systems (UAS) to more safely and efficiently:
- Inspect infrastructure
- Collect geo-spatial data about what’s on the ground in a particular location
- Conduct plant and animal species surveys
The picture on the LEFT shows a typical UAV flight pattern within Flood Control District boundaries, and the nearby property and road images that could be captured as part of that flight. The picture on the RIGHT shows the final rendered image provided to the Flood Control District, masking private property and areas outside of Flood Control District boundaries.
With jurisdiction over more than 2,500 miles of open and closed channels across nearly 1,800 square miles, and with limited staff, the Flood Control District anticipates a variety of potential benefits from the use of UAS:
- They make the inspection process safer for inspectors who often need to access waterways and enter remote, overgrown areas.
- They allow inspectors to cover more ground in a work day, as compared to boots-on-the-ground inspections.
- Future applications could utilize different image-capturing capabilities to identify plant stress, and quantify success of site stabilization and tree planting sites. These tasks help to determine when a project has been successfully completed by a contractor, or to identify contractor performance issues.
Flood Control District use of UAS technology is guided by both federal and state law, including the Texas Privacy Act. Recent contractors, HUVRdata LLC and Precision Aerial Compliance Solutions, are among UAS service providers vetted and credentialed by the National UAS Credentialing Program (NUASCP).
UAS over Brickhouse Gully
Beginning July 24, 2017, the Harris County Flood Control District will be using an Unmanned Aircraft System to conduct an infrastructure assessment along a 7-mile section of Brickhouse Gully, a concrete-lined tributary of White Oak Bayou formally identified as HCFCD Unit E115-00-00. An Unmanned Aerial Vehicle operated by Michael Baker International, a licensed Flood Control District contractor, will fly over and along Brickhouse Gully within Flood Control District right-of-way, from the gully’s confluence with White Oak Bayou upstream to Clay Road.
The UAS infrastructure assessment will be compared to those conducted by ground survey crews. Regularly assessments of Flood Control District property are necessary to efficiently and accurately study drainage infrastructure, to determine if replacement or repairs are needed.
The UAS flights along Brickhouse Gully will take place only during daylight hours, over a period of several days, dependent upon weather conditions.
UAS on Cedar Bayou
In June 2017, UAS sub-contractor InControl Technologies Inc. conducted an aerial environmental assessment of Harris County property near Cedar Bayou in northeast Harris County. Data and images were collected in connection with a Flood Control District project to evaluate creation of a wetlands mitigation site for the Cedar Bayou watershed. Cedar Bayou is formally identified as HCFCD Unit Q100-00-00.
A wetlands mitigation site is a protected area in which valuable environmental resources are created, restored, enhanced or preserved. In the future, this 240-acre site may be used to increase the amount of protected wetlands as a replacement for wetlands that will be impacted or destroyed by other projects elsewhere in this part of Harris County.
R.G. Miller Engineers Inc., project design engineer for the Flood Control District, is overseeing all field surveys and investigations, including UAS operations.
UAS on White Oak Bayou
In September and October 2016, the Harris County Flood Control District conducted its first test of UAS to measure and assess Flood Control District basins and drainage channel easements. Austin-based HUVRdata LLC, a Flood Control District contractor, flew over White Oak Bayou and three stormwater detention basins in central Harris County, roughly between Fairbanks North Houston Road and North Houston Rosslyn Road. After collecting more than 3,000 images and related data during two days in the field September 28-29, the company is now preparing its final report.
The contractor used an Ascending Technologies Falcon 8 to survey approximately 329 acres in the project area, measuring maintained vs. unmaintained areas, including some with tree cover. This is an 8-rotor, v-shaped Vertical Take Off and Land (VTOL) aircraft, which weighs less than six pounds. The use of UAS will be compared to the use of ground crews in performing similar measurements. Frequently updated measurements of Flood Control District property are necessary to the efficient and accurate management of contract maintenance services such as mowing, which are typically bid by the acre.
This area was chosen to test UAS capabilities over densely populated urban areas located directly adjacent to Flood Control District infrastructure.
According to project flight rules, the UAS fly over and retain data about ONLY Flood Control District-owned property and right of way. Flight rules require that the Federal Aviation Administration-certified Pilot In Command:
- Maintain visual contact with the aircraft at all times
- Avoid flying over or collecting data about any persons not directly involved in the demonstration project, which includes adjacent homeowners.
- Fly only during daylight hours.
UAS at John Paul’s Landing Stormwater Detention Basin
Flood Control District UAS contractor Precision Aerial Compliance Solutions conducted aerial topographic surveys at the Stormwater Detention Basin at John Paul’s Landing in northwest Harris County in 2016 and 2017. Data and images provided timely information about current conditions at the 283-acre site, where work progresses on a $1.8 million capital project to expand the stormwater detention basin. Quick completion of the topographic surveys helped avoid delays in the project, which began in 2015 and continued with a second phase in 2016-17.
The basin at John Paul’s Landing, located in a mostly rural area of the Addicks Reservoir watershed, is a key element of the Upper Langham Creek Frontier Program. John Paul’s Landing is the site of a future Harris County Precinct 3 park.
Stormwater detention basins reduce flooding risks and damages during heavy rain events by safely storing excess floodwater and slowly releasing it back to the bayou when the threat of flooding has passed.
(Photo at John Paul's Landing of Jason Nicholas, pilot in command, and HCFCD construction inspector Larry Rosenthal, courtesy of Precision Aerial.)