Words to Describe penstock

How penstock often is described ("________ penstock")

• closed
• foot
• single
• wooden
• longer
• inch
• diameter
• vertical
• welded
• common
• iron
• huge
• main
• open
• cylindrical
• particular
• second
• underground
• corresponding
• short
• riveted
• circular
• long
• separate
• horizontal
• large
• exposed
• stave
• concrete
• neat