WHEN you look at the Mimmshall Brook, in North Mymms, on a normal day you would never suspect such a stream would be capable of getting to such heights that at times it can flood a whole community.

However as history suggests, with decades of disastrous deluges on Warrengate Road residents’ homes, the brook bursting its bank is not a rare event.

So, in 2004, a �2m defence barrier was erected and since that date it has already protected the bungalows from devastation on two occasions – the last of which was in August after 1.5 inches of rain fell in a matter of hours.

This week the Hatfield-based Environment Agency, which built the steel construction as part of the Alleviation Scheme, which also saw a section of wall raised, invited the Welwyn Hatfield Times to the scene for its officers emergency response test.

It was an imaginary scenario on this occasion, yet the weather was so cold and windy that it proved an almost perfect replica for what will come when the Warrengate Road floodgates next have to be closed.

All that was missing was the overflow – but that is a substantial miss as the gates are so heavy that it takes two men a running head start to physically close them... and that’s without the mass of water.

The aim for the Environment Agency (its Thames NE Area Operations Delivery team) though is to get to the scene within at least two hours of the first call, no matter where they are, so hopefully on arrival there wouldn’t be too much water.

To calculate the amount of water there are electronic measuring devices up and down the river. The initial risk level of when the agency first starts preparing for action is around 76 metres above sea level.

Once on site the operation team has to close off the surrounding roads and put in traffic diversions.

Next step is to brush along the path where the gate closes and then to finally unlock it and get it closed.

Vanisha Lutchmadoo, who organised the exercise, said: “One in six properties in England and Wales are at risk of flooding.

“It is vital that our staff are trained and well prepared for any situation.

“This exercise is designed to test the skills, response and decision-making abilities of our officers during a flooding incident.”

She added: “These defences are an important part of how we can reduce the risk of flooding.”

To find out if your property is at risk of flooding and eligible for the Floodline Warnings Direct service, call the floodline on 0845 988 1188 or click on the link (top right).