The experienced duo have been Britain’s best two platform divers for years, but youngsters like Lois Toulson, Georgia Ward and fellow Plymouth divers Victoria Vincent, Robyn Birch and Shanice Lobb are pushing them hard.
However, Couch and Barrow showed their experience in Southend to handle the pressure and fill the top two spots.
World Series champion Couch won with a score of 346.80 points, with 2014 European champion Barrow just behind on 343.70 and teenage European Games champion Toulson third with 340.40.
In a high-class final, fellow Plymouth divers Birch was fifth (304.30), Lobb sixth (301.90) and Vincent seventh (290.25).
Afterwards Couch said: “It was an intense competition and I definitely felt that the pressure was on, but I focused on what I had to do and forgot everything else and that worked for me as I got the gold medal.”
There was an impressive debut from Tom Daley and Dan Goodfellow in the men’s synchro platform event.
Although they had no competition, after the late withdraw of another pair, Daley and Plymouth Diving’s Goodfellow produced an encouraging display to score 387.99 points, including more than 82 points for their final dive.
They will both compete in the individual event on Sunday, along with Matthew Dixon and Aidan Heslop.