Charlie Walker

Interested in driving change through sustainable solutions which meet society’s needs, not wants. A keen photographer outside of design.

Final Project

Aquapal | Accessible & Affordable River Health Testing Device

Currently only 14% of English rivers are in good ecological condition, with pollution causing significant damage to ecosystems. Aquapal addresses this pressing issue as a portable in-field testing device which enables regular river users to take action.

Aquapal prototype
Aquapal render

Intuitive Design

Specifically designed for the River Soar, Aquapal uses colorimetry technology and reagent tablets to test for three key parameters: dissolved oxygen, phosphate and nitrate. Abnormal concentrations of these parameters can indicate issues in the river, facilitating further testing with high-resolution equipment.

Holistic Approach

Through leveraging citizen science, pollutants are identified and data is demonstrated on an app, holding polluters accountable. Aquapal’s bottom-up approach engages communities in the protection of the natural world, promoting a sustainable future.

Bespoke Components

At the back of Aquapal is a tank, making collecting samples from the river straightforward. Samples are decanted into tubes for each of the three parameters before testing begins. The tubes are protected and hidden from external light by a sliding cap.

All-In-One Solution

Aquapal is accompanied by a carry case with slots for a cleaning cloth, reagent tablets, plastic gloves and a waste bottle to responsibly dispose of treated samples.

Purpose Built

An O-ring and conformity to IP68 ensures that all internal components are protected from the elements. Aquapal’s rugged and compact outer casing makes it suited for its environment. A removable battery cover at the base of the product allows the battery to be replaced and eliminates the need to discard the entire product.

Aquapal App

Aquapal’s app gives users the opportunity to better understand their test results in detail and view the data on a map. Test history for various locations can be viewed in order to see changes over time. The app brings the user closer to Aquapal and engages the company in the device post-purchase, ensuring circularity.

Prototype Development

Over the course of the project an iterative approach was undertaken with numerous prototypes built in tandem with research and sketch development.


  • Diploma in Professional Studies (2021-2022)
  • Gold Student Starpack Award (2020)
  • Architectural Photographer of the Year (LSU Media, 2020)
  • Certificate of Excellence in Product Design at A-level (2018)

Work Experience

Product Design Intern at Scope Design & Strategy, the Netherlands (6 months)

Visionary Thinkers

Visionary Creators

Visionary Makers