The event, at the Te Rapa pool in Hamilton, attracted 29 clubs from around New Zealand as well as an Australian under-20 team.
St Clair contested the championships with only 10 swimmers due to a large portion of its team being committed to university exams.
Despite being one of the smaller teams, it finished ninth overall, collecting two gold, two silver and six bronze medals in the process.
Carla Laughton and patient Chloe Harris won St Clair's first gold medal of the championships in the open women's line throw. Laughton continues to dominate the line throw event claiming her third national title in four years. The only year she missed out was to sister and club-mate Stephanie Laughton.
St Clair's other gold medal went to Jessie Schneiders in the under-16 women's 100m manikin tow with fins. Schneiders, a rising talent in the surf and on the sand, also showed her skills extend to the pool. A strong swim over the first 50m, aided by the large fibreglass fins and a skilled securing of the manikin into the rescue tube, allowed Schneiders to dominate the rest of the field.
The Laughton sisters teamed up with Carina Doyle and Chloe Harris and took the silver medal in the open women's medley relay. The St Clair foursome also claimed the silver medal in the open women's 4x50 obstacle relay.
Richard Harris took bronze in the open men's 100m manikin tow with fins and the open men's 100m manikin carry, and Doyle secured an individual bronze in the under-19 women's 100m manikin carry.
Jamie Mowat grabbed a bronze medal in the under-16 men's 100m rescue medley. Sisters Jessie and Lulu Schneiders shared third in the under-16 women's 50m swim with fins.
