Replacing spreadsheet billing for a regional water utility
A full commercial platform covering meter reading, tariff calculation, invoicing and mobile money collection for a utility serving tens of thousands of connections.
Client: Regional water utility (anonymised)
- Reading to invoice, from several days
- Same day
- Payment reconciliation, previously weekly and manual
- Automated
- Readings lost to connectivity gaps in the field
- Zero
- Non-revenue water, measurable for the first time
- Visible
Readings were captured on paper, keyed into spreadsheets days later, and billed against tariffs maintained in a separate workbook. Nobody could say with confidence how much water had been consumed but not billed. Collections relied on customers walking to a counter, and reconciliation between the cashier's book and the bank happened weekly at best.
We deployed AQUAOS: an offline-first Flutter reading app with route sequencing, photo evidence and anomaly prompts; a rules-based tariff engine supporting category and consumption bands; automated invoicing per cycle; and mobile money integration reconciled against receivables the moment a payment settles. A migration pipeline validated and loaded historic customer, meter and balance data before cutover, with parallel running for two full billing cycles.
Technologies used
- Next.js
- TypeScript
- Flutter
- Node.js
- PostgreSQL
- Redis
- Docker
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