Litmus Towers

The ‘Litmus Towers’ (or ‘towers of lights’ or ‘those strange towers along the A13’) were installed in 2005 on four adjacent roundabouts, as a large scale artwork which would display data about the surrounding environment, hence the name.

Each Litmus Tower is made up of a 12 metre high galvanised steel frame, topped with 175 carbon fibre tubes with a single coloured LED at the end. The LED’s work together to display data in the form of numbers, to people travelling on the surrounding roads.

tower of lights rainham A13 marsh way

The Four Litmus Towers

The situation of each Litmus Tower was carefully considered to draw attention to the surrounding brownfield land, and promote the forthcoming regeneration of the area. Each Litmus Tower is designed to display different data, as follows:

  1. Marsh Way North – traffic counter, showing how many cars have used the slip road and displaying the figure in turquoise lights
  2. Marsh Way South – displaying power generated by the nearby wind turbine, in kilowatts
  3. Ferry Lane North – demonstrating the light level, in lux
  4. Ferry Lane South – illustrating the tidal level nearby, displayed in yellow

History of the Litmus Towers

In 2012, funding was secured to refurbish the Litmus Towers. Originally constructed with a steel frame supporting acrylic panels, the Towers had begun to experience some degradation due to the environmental conditions they were exposed to. Foliage had also begun to grow inside the Towers, causing potential issues with electronics.

litmus tower before refurbishment

A thorough analysis of the condition of the Towers identified several areas for improvement.

1. Materials – the decision was taken to replace the acrylic panels with an anodised aluminium exterior, better able to withstand external forces whilst still retaining the original brief for the Towers.

2. LED’s – knowledge of LED behaviour has increased significantly since the Litmus Towers were originally installed. Complete replacement was recommended, with redundancies built in to ensure that the failure of a single LED will not cause failures of surrounding LED’s – something which was an issue with the original Towers as the LED’s were clustered in groups of 3.

3. Power and control – inadequate sealing had allowed spiders, slugs, snails and damp to access the control panels, leading to corrosion.