Island Water Park, a proposed recreational water sports facility heralded by Riverhead officials as a major tourist attraction and economic development initiative, has been issued a stop-work order by the town.  The order was issued Monday after town officials determined the developer of the facility was doing construction at the site without site plan or building permit approvals, according to Building and Planning Administrator Jefferson Murphree. Murphree said in a call on Wednesday the developer had done unpermitted grading and drainage work, and interior construction pouring concrete for an indoor wave pool. Island Water Park obtained preliminary approval from the town board July 7 for a revised site plan covering…