The flood sirens in Grimsby and Cleethorpes will be tested on Friday.
The 18 sirens were installed in 2006 and are used to warn more than 25,000 households and businesses about imminent tidal flooding.
The siren on the Willows Estate, Grimsby is also used to warn residents about flooding from the River Freshney.
The Environment Agency has said the sirens will be tested on Friday, August 29 between 10am and noon. Each group of sirens will be sounded three times for between 2 and 5 minutes. The siren will be followed by a voice message to advise a test is taking place, then a voice message will be heard giving a Severe Flood Warning. Once the message has finished, a wailing noise will be made and a message to confirm a test has been carried out will be played.
Environment Agency staff will be in the Freshney Place Shopping Centre on Thursday, August 28 from 9am to 5pm to answer questions about the sirens and flood risk.
The sirens were put into action last year when one of the most severe storm surges in 60 years flooded parts of Grimsby, Cleethorpes and Immingham.
On December 5, the sirens were repeatedly sounded while hundreds of residents were evacuated as a precaution.
Claire Rose, Flood Resilience Team Leader at the Environment Agency, said "Our flood defences reduce the risk of flooding to thousands of homes and businesses in Grimsby and Cleethorpes, but there is always a risk that they can fail or be overwhelmed.
"It is important people know what to do before, during and after a flood and identify actions they can take to protect themselves and their property. We'd love people to come and see us in Freshney Place to learn more about flood risk and what they can do to help themselves.
"It is important we test the sirens to make sure they will work during an emergency but we would like to apologise for any inconvenience the testing may cause."
For more information about flood risk call Floodline on 0345 988 1188 or visit www.environment-agency.gov.ukThe 18 sirens are located at: Blundell Park (Grimsby Town FC), Freshney Place shopping centre, Nelson House, People's Park, Grant Thorold Park, Sidney Park, Allotments adjacent to Kelham Road and Algernon Street, WIllows Primary School, Littlecoats Primary School, South Parade Junior School, Waterworks Cottage Lane, Edward Heneage Primary School, Reynolds Junior School, Old Clee Junior School, Cromwell Road/Boulevard Avenue, Park Street, Augusta Close.
