A call is to be made for a council to help clean up Norwich's most polluted street - by installing mossy air filtering technology.

Norfolk County Council is due to agree its budget for the forthcoming year on Monday.

But the opposition Liberal Democrat group is tabling an amendment to that budget, in which councillors will call for two CityTrees to be installed in Castle Meadow.

CityTrees, made by green technology firm Green City Solutions, use plants and mosses to filter pollutants from the air.

They have been trialled in a number of cities across the world including Amsterdam, Paris, Oslo and London.

A CityTree powers itself via solar panels, and rainwater is collected and redistributed using a built-in irrigation system.

They can provide a meeting area for people to sit, surrounded by clean air.

Norwich Evening News: Steffan Aquarone, leader of the Liberal Democrat group at Norfolk County Council. Picture: Alex BroadwaySteffan Aquarone, leader of the Liberal Democrat group at Norfolk County Council. Picture: Alex Broadway (Image: Alex Broadway © 2019 - alex@alexbroadway.co.uk - 07905628187)

Steffan Aquarone, leader of the Lib Dem group at County Hall, said it would cost about £60,000 to install and maintain two CityTrees in Castle Meadow.

He said: “We think CityTrees are a fantastic innovation that would fit well in our city. They combine the best of environmental solutions with attractive street furniture, and even WiFi hotspots.

“With environment and climate change desperately needing to be at the heart of everything Norfolk County Council does, we hope this is a no-brainer for the council to show it’s serious about leading the way in improving air quality and tackling climate change in Norfolk."

Analysis of air quality in Castle Meadow, carried out by Friends of the Earth, showed the street - which is off limits to general traffic but much used by buses - had levels of nitrogen dioxide above safety targets.

The nitrogen dioxide level there was recorded in 2018 at 54 micrograms per cubic metre of air, above the average air quality target of 40 micrograms.

Green City Solutions say that CityTrees can filter 3,500 cubic metres of air every hour, which corresponds to the hourly breathing volume of about 7,000 people.

The Conservative-controlled council's budget, which includes a council tax increase of almost 4pc, will be decided in a virtual meeting on Monday.