Satoshi's Sidewalk #5: What to do With All That Water
Everyone has a plan until they find out where the water flows are.
Let’s say you’re working on a brand new development. You’ve tied up the land and have big plans. Start allocating space for streets, homes, commercial centers. We’re talking Master Planned Utopia. All is neat and orderly.
All of your scheming rests on one assumption: the water flow estimates are correct.
The saying goes that there are two certainties in life: death and taxes. We can append this with “there will only ever be 21 million bitcoin” and “the water must go somewhere.”
In an urban setting, water is off-loaded from the property to the city’s stormwater waste system. Urban areas lack storage facilities, and the land is better utilized for other purposes. Downtown areas and city centers were typically founded at higher elevations than the surrounding terrain and water flows naturally leave or flow around the city. This works until it doesn’t. Land area expansion of a city moves towards the next highest elevation until the lower areas are all that remain.
Depending on the state, water flows cannot be “dumped” and cities must have a method for ultimate mediation. Phoenix occupies what is known as the Salt River Valley which has pre-existing washes and “rivers.” Water flows are channeled to the Gila, Salt, and Agua Fria Rivers. Without these river outlets the stormwater waste systems simply do not exist.
Suburban developments are required to carry their own water for a certain period of time. This is commonly known as X-amount of years flood - a 100-year flood for example. A developer and the civil engineer are required to design the drainage of a site to hold a once-in-a-hundred year storm for Y-amount of hours. Rainfall over that amount is no longer the responsibility of the developer.
There are many ways to control water flows. Some inexpensive and above ground, some incredibly expensive and below ground. Suburban projects use the former and not the latter method. This uses up more land for non-productive activities. Suburban land not developed is natural geographic land which can absorb the water, instead of flowing down paved streets.
With development, the water must flow.