Using Low-Cost Equipment to Gather High Precision Data for Flood Modeling

An impact story

By: OMDTZ team

In collaboration with Deltares and with funding from GIZ, OMDTZ was able to collect accurate and precise river cross-section surveys using an innovative, low-cost technique developed by the Resilience Academy and OMDTZ. This is one of the first services by a local firm in Tanzania based on a new affordable chipset that allows for cm-precise GPS surveying. More services such as much needed cadastral mapping will follow.

A surveyor in the field holding a locally made survey tool in RTK mode

The low-cost technique makes use of a first of its kind affordable GPS chipset, that can provide cm-precise surveys. Professional grade equipment delivering this sort of precision normally costs in the order of 2,000 to 10,000 USD, but this equipment can be acquired for about 300 USD. Connected with a smart phone with the OpenDataKit surveying app, this opens doors to powerful services for e.g. much needed cadastral mapping, hydrological surveys, subsidence surveys, satellite ground-truthing and terrain reconstructions.

Recently, OMDTZ wrote an exciting blog about this, with contributions from the Resilience Academy and Deltares, showing one of their first services. They delivered very accurate river cross section data for the Msimbazi river, that knowledge institute Deltares, The Netherlands, consequently used to establish an accurate flood simulation model.

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Surveyed cross section locations
One of the surveyed transect, visualized in 3d using a Digital Terrain Model
A screenshot of one of the flood hazard maps produced using the new survey data

Universities in Tanzania working on Climate Risk Data Repository, University Student internships cooperation and develop open-access edu materials and training.

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