AGMARDT funded laboratory testing for Rivershot’s programme to develop ways to use satellite science to measure river water quality

“RIVERSHOT is an intelligent and innovative approach to water quality that is data-driven, highly directed, inquisitive and comprehensive in its commitment to learning and understanding,” says Paul Brown.

Former dairy farmer Paul, from Ashburton, is one of the core team of three driving development of the innovative programme which uses a combination of satellite-based spectral analysis and direct water sampling to monitor changes in river water quality and to identify nitrogen and e-coli levels.

AGMARDT provided funding to support regular testing of water samples during 2020 and 2021 to help RIVERSHOT test and adapt its processes.

“As a dairy farmer, I was very aware that dairy farming is blamed for a lot of river pollution and I wanted to look at ways to help,” says Paul. “The other members of our team are a computer scientist and a space scientist .

“RIVERSHOT portrays water quality by continuously tracking the extent of Nitrogen and E. coli content along the river. It works through a mixture of absorption, refraction and reflection of wavelengths. It is very complex but, by measuring wavelengths, you can detect what is in the water.”

While satellite-based programmes for analysis of lake water quality are already established, Paul  believes Rivershot technology is a world first for monitoring river water.

“Lakes are larger and more stable. Rivers are not as wide or deep and they move faster and weave through hills and urban and rural environments and various industry. There is the potential to monitor every river in New Zealand using this – and overseas too.

“Rather than taking river water samples in a handful of locations monthly, Rivershot looks across the whole river, taking up to 2000 test points per km, and averaging them over a length of river. Results will be presented within 48 hours of satellite imagery.”

Paul is funding technology development costs for the project and the AGMARDT funding enabled regular laboratory testing of river water samples to check against satellite analysis.

Initial pilot programmes were undertaken on the Avon, Cam, Kaiapoi and Rakaia rivers, with water samples taken on the same day as satellite imagery. The data set and analysis is being independently peer reviewed.

“We did a lot of testing with satellites and, at the same time, did traditional bucket testing,” says Paul. “We also used water testing data from LAWA (Land Air Water Aotearoa) to correlate our results.

“It’s been a constant process of developing our technology to overcome issues like flow and distinguishing stones from water. There have been many steps in the process but we have successfully demonstrated the process of using satellites to measure N and E. coli is possible on different types of rivers within NZ. We are now processing data from 60 rivers – mostly in the South Island but some in the North too.

“As an example, the Avon is one of the most tested rivers in the South Island – it is tested in seven places monthly by agencies like ECan and Christchurch City Council.. In one day, Rivershot can get 1,500 samples from the Avon. The Rakaia river is tested in two places monthly; we can get a shot every metre and over 50,000 samples in one day.”

The Rivershot team is now seeking partners to help take the programme to its next stage and ultimately to facilitate its uptake by agencies, government, independent groups and business groups, who can use it for their needs.

“We want to work with the right people for the right reasons,” says Paul.  Rivershot contributes to a sustainable river eco-system that benefits everyone.  Our system is a more holistic view of the whole river system and presents the results to clients very quickly. Therefore results can be acted upon  by those that monitor our rivers in real time to help prevent further pollution. Rivershot helps tell the whole story of the river , the good and the bad, as it passes through different localities that can effect water quality.

“Our aim is to become the trusted supplier of regular data from all possible fresh water rivers and waterways, and supply agencies, farmer groups, water care groups and individuals, that require this information to carry out their regulatory roles and maintain our fresh water standards for the benefit of all New Zealand.”