Five years after Winter Storm Uri, San Antonio utilities expand winterization, backup power, and coordination

System failures in 2021 drove new operational and infrastructure priorities

In February 2021, Winter Storm Uri triggered widespread service disruptions across Texas, exposing weaknesses in electric generation, fuel supply, transmission and distribution systems, and water infrastructure. In San Antonio, both the city-owned electric and gas utility CPS Energy and the San Antonio Water System (SAWS) have since pursued upgrades aimed at limiting the risk that extreme cold and extended outages could again cascade into citywide power and water emergencies.

CPS Energy: earlier forecasting, grid automation, and winterization work

CPS Energy has expanded its pre-storm communications and strengthened internal weather monitoring by adding specialized forecasting capability. Operationally, the utility has also emphasized tools designed to shorten outage duration and reduce the number of customers affected by individual equipment failures.

A major focus has been the deployment of distribution automation equipment, including “smart switches” and related devices that can isolate faulted sections of the grid and reroute power where feasible. CPS Energy has also highlighted redesigned outage-mapping tools intended to improve customer transparency during restoration efforts.

On the generation and transmission side, CPS Energy has described winterization measures that include insulation and heat-tracing systems, sensors and thermostatic controls, and temporary enclosures intended to keep critical components within operating temperature ranges during freezing weather. The utility has also reported expanded vegetation-management work to reduce weather-driven line faults tied to tree contact, which can increase during freezing rain events.

• Distribution reliability: expanded use of automated switching designed to limit outage footprint
• Plant and transmission readiness: winterization measures to reduce cold-weather equipment failures
• Operational resilience: inventory readiness for emergency repairs and restoration

SAWS: large-scale backup generation strategy for pump stations

For SAWS, one of the central post-Uri initiatives has been backup power for pumping infrastructure to help maintain water pressure during extended electric outages. SAWS has pursued a multi-site generator program, including shared arrangements in which SAWS funds acquisition and installation while CPS Energy operates certain generators and may use them under defined conditions.

SAWS has also carried out winterization at pump stations, including insulation for exposed above-ground equipment and other protections intended to reduce freeze-related vulnerability.

Maintaining water pressure during long-duration power loss has been a primary planning target, with backup generation prioritized for critical pumping locations.

Statewide framework: stricter weatherization requirements and more inspections

After Uri, Texas adopted new weatherization requirements affecting portions of the electricity supply chain, including standards and enforcement structures for generator and transmission readiness. Natural-gas sector rules also took effect in 2022 requiring weatherization compliance at covered facilities. ERCOT has expanded winter preparedness activities in recent seasons, including additional inspections and programs aimed at supporting reliability during cold-weather peaks.

Inter-utility coordination becomes a formal part of severe-weather response

CPS Energy and SAWS have described strengthened coordination protocols for severe weather, including data sharing and joint planning to align restoration priorities and protect critical water and power assets. The shared objective is to reduce the likelihood that electric disruptions propagate into water-system failures, while improving restoration sequencing when outages occur.

Even with added redundancy, both utilities have emphasized that extreme weather can still produce service interruptions; the post-2021 effort has centered on reducing duration, limiting the scope of outages, and preserving core functions during prolonged cold events.