Then there is also an economic factor. When a new suburb forms, they may no be able to afford a wastewater plant. So they may pay the bigger city to treat the water and wastewater for the new suburb. Usually a win-win because those people moved from the bigger city. But over time the suburb grows, all the problems above start happening and the bigger city generally has less revenue. The bigger city's plant is falling apart, they want to pay to rehab it. If big city raises rates the now mega-suburb might find it cheaper to go build their own plant rather than piping it back to big city. If that happens big city would need to build a brand new plant, which will cost more than the rehab. But without raising rates they can't pay for the rehab. So then nothing happens for years.