abandoned
canal
cave
construction
corridor
creepy
dark
dirty
drain
drainage
dry
duct
escape
fear
flow
grunge
grungy
horror
industrial
industry
municipal
mystery
outfall
passage
pipe
pipeline
precipitation
rain
rainwater
rough
runoff
rusty
sanitary
scary
sewage
sewage system
sewer
sewerage
storm water
stormwater
stream
system
tunnel
underground
urban
waste
wastewater
water
waterpipe