📋 Case Study

Midwest Water Utility SCADA Modernization

Incompatible RTUs, no remote diagnostics, and chronic historian data loss during comms outages

🏗️ Project Overview

Legacy DOS-based SCADA upgrade across 17 pump stations and 3 reservoirs

🎯 Challenge

Incompatible RTUs, no remote diagnostics, and chronic historian data loss during comms outages

🔧 Design Approach

Phased deployment of OPC UA-enabled edge gateways with local SQLite buffering + MQTT telemetry to cloud historian

📐 Design Diagram

AI-generated project design illustration

📐 Key Calculations

Buffer Depth Requirement

Scan Rate × Tag Count × 15 min retention

Result: 2.1M records

Ensures zero data loss during 15-min WAN outage

MQTT QoS Selection

QoS 1 for critical alarms, QoS 0 for trend data

Result: Optimized bandwidth vs. reliability tradeoff

Reduced bandwidth by 42% without sacrificing alarm integrity

📊 Results

99.992% data availability, 70% reduction in truck rolls, full remote firmware updates enabled

💡 Lessons Learned

• •Local edge buffering is non-negotiable for rural WAN links
• •MQTT topic hierarchy must mirror physical asset hierarchy for scalability

✅ Key Takeaways

• 1Local edge buffering is non-negotiable for rural WAN links
• 2MQTT topic hierarchy must mirror physical asset hierarchy for scalability