The residents blocked the N2 highway between Sir Lowry’s Pass and Hazeldene on Monday.
Residents barricaded the road with concrete slabs, burning tyres and other debris. Some were seen destroying traffic lights.
The demonstrators are reportedly unhappy with electricity and other service delivery issues in the area.
“A charge of public violence is being investigated and 19 people have been arrested
[17 males and two females],” police said in a statement.