Case Study: Sheppard Air Force Base Stormwater Survey

The Halff-led project team is setting new standards in stormwater asset management through the U.S. Air Force’s Sheppard Air Force Base project.

Keeping the military base and airfield functional for pilot training is extremely important for Sheppard Air Force Base (AFB). This survey and evaluation helped the Base achieve these goals, where high-impact and time-constrained deliverables did not stop the team from taking an innovative approach.

Background

Many military bases—including Sheppard Air Force Base in Wichita Falls, TX—have been directed in recent years to conduct asset inventories and condition assessments on their water, wastewaster and stormwater systems to determine the impact on environmental compliance.

As an active training base, Sheppard AFB has faced an increasing number of compliance and flooding issues due to aged and degraded stormwater infrastructure and increased development. Conducting a detailed inventory and assessment of the stormwater system is essential to meet environmental standards and guarantee uninterrupted operation of the airfield and base activities.

The project evaluated storm-sanitary cross connections due to high levels of infiltration and inflow.

Halff was contracted by SLA-Cyntergy to conduct a storm drain survey, database integration and hydrological and hydraulic (H&H) study of the base’s existing storm drain system. Sheppard AFB needed a comprehensive understanding of the base’s stormwater infrastructure to manage assets effectively and mitigate flooding risks.

This project required evaluation of the current stormwater system to make recommendations for system improvements. Tasks in the evaluation included a thorough review of the base’s stormwater system asset inventory, data-gap analysis, system-wide condition assessment with engineering repair prioritization, spatial database integration of all findings and system-wide H&H modeling.

The deliverables produced the necessary information to define stormwater system sub-basins, to update the base-line stormwater system asset inventory and condition and to deliver the critical improvement recommendations needed at the base.

Challenges

The Halff team was presented with a substantial challenge: they had to update an extensive GIS asset inventory for Sheppard AFB, which included numerous assets that were either outdated, erroneous or missing entirely.

A project of this magnitude would ordinarily span multiple years, but due to the urgency of supporting H&H modeling efforts, it was imperative to complete the inventory within a single year.

There were a significant number of assets missing from the inventory, and the discovery of unknown pipes in the GIS data were especially important for the project’s flood modeling component.

The project involved a thorough manual review, quality control and data integrity checks of the existing asset inventory in GIS and CAD. While the GIS database was built before this project, the dataset required many updates to make it an accurate representation of today’s physical system. These updates involved system-wide field data verification and correction, which further impacted the project’s scope and approach.

The project team encountered additional challenges due to Sheppard AFB’s strict database schema, which did not align with Halff’s usual setup and adaptation. It would require the Halff team to get creative and use a different approach to ensure accuracy.

Approach

Coordinating all the moving pieces required the right technology, excellent QA/QC and above all, communication.

Four teams and the prime, SLA-Cyntergy, were involved in the project, as well as air force base staff. Halff performed GIS, surveying, infrastructure engineering evaluation and water resource services for Sheppard AFB. The Halff-led project team carried out a comprehensive storm drain GIS inventory and condition assessment, which used several key techniques:

• • • Field data acquisition technologies: The team collected a massive amount of media and CCTV data with the help of mobile surveying and 360-degree manhole scanning.
    • GIS technology standards: Halff adhered to GeoBase guidelines to ensure best practices and standards were met while conducting a condition assessment and stormwater asset inventory, which facilitated the H&H modeling of the stormwater system at Sheppard Air Force Base.
    • Computer vision: Artificial Intelligence (AI) machine-model review helped support a “second opinion” QA/QC of defects by flagging discrepancies between AI-detected defects and vendor-reported pipe defects for further manual review.

The use of a machine-learning object detection model came from the need for a more detailed review, offering a cost-effective solution.

Tools like Python and Arcade attribute rules were used by Halff’s project team to maintain data integrity and mass populate survey data during the database updates. To supplement the base’s pre-defined database schema, Halff established additional GIS datasets to house field-gathered data, images and videos. This approach ensured the comprehensive capture and referencing of all essential information.

This graphic (left) displays CAD symbology representing a grate inlet, included as polylines. The recommended update was to remove the CAD polylines and add a grate inlet. The storm drain pipes were then updated to connect to the new inlet point.

Accuracy was essential for preparing high-impact deliverables. To effectively prioritize maintenance activities or capital projects, base staff need to know the accurate, relevant characteristics of modeled features, including locations and asset counts. Industry best practices for asset management were utilized to support the inventory maintenance in support of the hydraulic modeling effort.

Field data was incorporated to update the existing GIS information, and the revised storm drain GIS dataset was transferred to (H&H) modelers for system-wide drainage analysis.

Halff’s survey team collected lidar scans of inlets to aid in evaluation and analysis of the storm drain system.

Final project deliverables included a fully updated stormwater utilities GIS asset inventory, survey and condition assessment datasets, and recommendations with planning-level cost estimates for repair, replacement and improvements to the base’s stormwater system.

Results & Benefits

The critical insights gained during the inventory and condition assessment led to effective engineering recommendations for system repairs and upgrades.

Much of the project’s success can be attributed to Halff’s excellent organization of data, skillful use of tools, and thorough communication among the teams, subcontractor and client. Communication across multiple disciplines, excellent review and QC of high-impact deliverables, and the application of an AI computer vision model enhanced project efficiency and accuracy.

New stormwater assets that were collected brought greater accuracy from the original data (left). Field verification enabled more accurate representation of the storm drain system in advance of H&H modeling.

The unique combination of GIS technology, engineering evaluation of stormwater infrastructure and hydraulic modeling helped enhance Sheppard Air Force Base’s stormwater management in a powerful way. This project not only met U.S. Air Force GeoBase requirements, but also set a new standard in stormwater asset management.

The Halff-led project team achieved significant success in enhancing stormwater management at Sheppard Air Force Base through an innovative approach. By conducting a comprehensive field survey, condition assessment and meticulous GIS updates, the team provided critical insights that led to effective recommendations for system repairs and upgrades.

A more resilient and strategic future is now possible for Sheppard Air Force Base with actionable insights and a foundation for success, to keep the airfield functional for years to come.

Need expert help from Halff? Our talented industry professionals bring years of expertise and knowledge for your projects.

Let Halff help you take the first step contacting GIS Team Leader Jennifer Worthington (jWorthington@halff.com) or AI/Infrastructure Management Team Leader Matt Stahl (mStahl@halff.com).