The hospice is looking for people to join the Hertfordshire team New Kids on the Dock to take the plunge and help raise vital funds.
But hurry, because entries close on Friday, May 27.
Team leader Fran and her five-strong team are self-confessed rookies when it comes to swimming al fresco.
But the long-term friends, who met when they lived in Nottingham more than a decade ago, say they love how invigorated they feel after a training swim and can’t wait to catch up when they dive in on Saturday, May 28.
“We’ll probably swim breaststroke so we can chat as we go!” says Fran, who completed her second practice swim in Denham last weekend. She hopes to cover 1.5km on the day but says the team members will probably end up swimming different distances.
She added: “Some of us haven’t swum more than a couple of lengths for many years so we’re each working on technique and stamina but taking it at our own pace.”
Fran swims in an indoor pool most Thursdays when she takes her daughters swimming but admits the open water swimming is a very different experience.
“Ever since some of us sampled open water swimming together on a camping weekend last year, where we jumped into a freezing cold lake in just our swimming costumes, we’ve found it really invigorating. But since that first dip - wetsuits have been a must!”
The cause is close to Fran’s heart too. As a former events fundraiser for Rennie Grove, she knows how much work goes into hosting these events – and how important the charity’s unique service is in the local community.
“Already this year, three of our neighbours have needed the nurses’ care,” she says. “It all just feels particularly relevant right now.”
Sign up online before 11 am on May 27 and choose from the charity’s ‘get in and splash challenge’, loops of 100m to 750m in distance or 5K plus for experienced open water swimmers.