Fifteen years after the Deepwater Horizon oil rig exploded off the Gulf Coast, killing 11 and sending 134 million gallons (507.2 million liters) of crude gushing into the ocean, the effects of the nation’s worst offshore oil spill are still being felt.

Oil company BP paid billions of dollars in damages, propelling ambitious coastal restoration projects across five states. Yet cleanup workers and local residents who suffered health impacts they attribute to the oil spill have struggled to have their cases heard in court and few have received significant compensation.

Conservation groups say the spill catalyzed innovative restoration work across the Gulf Coast, but are alarmed at the recent halt of a flagship land-creation project in Louisiana. As the Trump administration expands offshore oil and gas, they are concerned the best opportunities for rebuilding the Gulf Coast are slipping away.