AN investigation has been launched into the consequences of the storm that hit the city on Monday August 13, when more than 40mm of rain fell on the city in just over 15 minutes - leading to flash flooding.

A flood plan update report prepared for City of York Council’s executive member for environment, Cllr Andrew Waller, says more than 120mm of rainfall per hour was recorded in the city earlier this month and the Flood Risk Management Team is examining the consequences. Traffic was reduced to a crawl on several key streets, including Fulford Road, and firefighters were called in to help out after an Acomb property started flooding. Water Lane in Clifton was also closed after it was inundated with rainwater.

The report says: “Rainfall of this extreme nature will continue to test any drainage systems with significant ponding as the sheer volume of water cannot get into a full clear and cleansed system. We all need to consider how we can design, build, manage and live in infrastructure, homes and businesses that are resilient to such storms and the challenges we face with climatic change.”

The report says more than 23,000 of the city’s 43,000 gullies have been left “in a free running state” since the start of a cleaning programme. Officers said: “We have observed that the work completed to date has reduced the impact of a number of significant rainfall events on key areas across the city.”

But more than 900 drains were found to be in need of “significant engineering work” to improve the situation. Capital funding of £250,000 a year for the next three years has been put towards surveying and cleaning the network.

Community emergency plans and training are also being developed with parish councils.