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TP108 Rainfall Charts — Auckland Design Rainfall Map Selector

Select return period and pinpoint site rainfall from Auckland Council TP108 2-year, 10-year and 100-year design rainfall maps. Apply SW CoP climate change factors for NZ stormwater design.

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What this tool does

Auckland TP108 Rainfall Maps

Reference 2-year, 10-year and 100-year 24-hour design rainfall depth maps from Auckland Council Technical Publication 108 (TP108).

Climate Change Adjustment

Apply Auckland Council SW CoP climate change factors (2.1°C or 3.8°C temperature rise) to derive adjusted design rainfall for modern stormwater design.

Interactive Site Marker

Click on the rainfall map to drop a site marker, zoom and pan to pinpoint your location, then read off the rainfall percentile value.

Save & Restore Per Project

Persist selected return period, map marker position, and adjusted rainfall values against a project, then reload them later or update the saved record.

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Open TP108 Rainfall Chart Selector

Part of the Flowpath Engineering suite of free civil engineering tools for New Zealand.