Effective December 19, 2008, all public swimming pools and spas must be in compliance with the provisions of the Virginia Graeme Baker Pool and Spa Safety Act.  The Act requires that all suction outlets be equipped with ANSI A112.19.8 - 2007 approved VGB covers.  If the pool is not designed with split main drains and equalizers (with drains separated at least 36 inches apart), the pool must have unblockable drains or have a secondary safety device, such as a safety vacuum release system (SVRS).

Many pools do not comply with the new law by merely changing the main drain covers, because the sump below the drain covers must meet the manufacturer's written specifications. In some cases, this will involve modifications and design of a new sump.  I can help with these.
In California, a C-53 contractor's license is required to modify the sump.