Possible Clues:

• See-through
• Clear
• Clear spring after flowed into river
• See-through patterns ran randomly
• Like a glass - and it could make parents rant
• Able to be seen through
• Unpolluted river flowing round resort - managed to get over
• Coaches not needing one generator? That's clear
• Managed second, even in temporary accommodation, that's clear
• Easy to see or impossible to see