Lingering concerns over water quality on O'ahu's south shore will affect at least two surfing contests this month.

The T&C Grom Contest and Air Invitational scheduled for this weekend at Queen's Surf, Waikiki, has been canceled. More than 150 youth surfers were expected to participate in the Grom Contest (the Air Invitational is for professional surfers).

"Because our event involves young children, we didn't want to take any chances," T&C Surf marketing director Lani Isherwood said. "We considered alternate dates, but permits are difficult to get, especially during the summer. We'll just look forward to coming back next year, hopefully."

Also, the Local Motion Surf Into Summer contest will be held at Sandy Beach, May 27 to 29. It was originally scheduled to take place at the Ala Moana Bowls, near Magic Island.

"We consulted with our major sponsors, and all agreed that it wasn't worth the risk to keep the event at Bowls this year," Local Motion marketing director Mitch McEwen said.

The Surf Into Summer normally draws more than 300 entries, and is considered the largest amateur surfing contest in the state.

'EDDIE' WATCH WILL CONTINUE THROUGH 2016

Quiksilver reached an agreement to remain the title sponsor of the Quiksilver In Memory of Eddie Aikau Big Wave Invitational surfing contest through the 2015-16 winter season.

The event can run at Waimea Bay only on a day when traditional wave heights reach at least 20 feet. Because of its strict standards, it is considered one of the most prestigious events in all of surfing.

"It is our commitment to the Aikaus, and to the memory of Eddie, that we will ensure this event stays true to its roots, continuing on as a living tribute to Aikau and to the brotherhood of big-wave riding," Quiksilver chief executive officer Bob McKnight said.

The event has been completed just seven times since the first one in 1984. The contest was not staged last season because wave conditions were never up to standard during the holding period.

The event was created to honor Eddie Aikau, a former big-wave surfer and lifeguard at Waimea Bay who was lost at sea during a solo rescue attempt for the voyaging canoe Hokule'a. Aikau would have been 60 on May 4.