2017 July 19  I just talked with a friend whose job involves streetwater harvesting.  According to her, in most parts of Tucson the aquifer is too far below ground level for water collected by raingarden basins to reach it.  She says when I talk with City officials I’ll probably have most traction if I focus on how streetwater harvesting benefits stormwater management, especially since the City of Tucson is distributing sandbags to help deal with this year’s monsoon flooding.  I’ll research raingardens and aquifer recharge more, but in the meantime I’ve revised what I wrote yesterday.  

2017 July 18 Watershed Management Group has a vision of restoring Tucson’s “heritage of flowing creeks and rivers”. To do that, we as a community have to start putting more water back into the ground than we take out. Restoring the historic flow of our waterways seems like a good goal. So, consistent with regenerative sustainability principles, Campus Farm Green will minimize its water use and aim to recharge more water than it uses.

But on the typical sized city lot, not enough rainwater to offset residents’ water use falls on the property. One water conservation/recharge method that holds promise to get around this problem and provides multiple associated benefits is to harvest the rainwater collected by streets.

Tucson ordinances now allow curbs, which traditionally act as mini-levees to flooded streets, to be breached so that streetwater can flow into raingardens between the curb and the sidewalk. The water enables the trees, shrubs, and groundcover in the raingardens to flourish, which improves the streetscape. The gardens reduce and help manage stormwater in the street and clean the water while returning it to the ground.

Unfortunately the current streetwater harvesting ordinance allows the water to be used only on public land. This severely limits water harvesting potential and means that as things now stand Campus Farm Green can’t be developed to harvest streetwater.

We’ve talked with a variety of City officials about this. All are in favor of allowing streetwater to be used and recharged on private property, but so far the regulations haven’t been revised to allow that. But we’re continuing the dialog and hopefully change will come soon enough that Campus Farm Green will be able to harvest streetwater to help achieve its goal to put more water back into the ground than its residents use.