A judge said the charges, which could have set a dangerous precedent against nonviolent protest, should never have been brought.
Newark distributed filters and took measures to address lead in its water supply, but residents say they don't go far enough.
On Wednesday afternoon, the Stansted 15 walked out of court free after the judge in the case declined to send them to prison.
The Stansted 15 face years of imprisonment after they stopped a plane from carrying asylum-seekers to countries where they may have faced persecution.
The Stansted 15 shut down an airport to stop the British government returning asylum-seekers to countries where they may have faced persecution.