Volume 1
In Volume 1 see appendix 8: Wind Harvesting: Basic Airflow Relationships, Site Selection, Wind Pumping and Wind Power, Natural Ventilation, Windbreaks, and Snow- and Biomass-Drift Harvesting
Snow & Wind Harvesting
Well-placed and spaced vegetation or even a fence can create a windbreak or shelterbelt that slows wind speeds, allowing the snow, rain, organic matter, and/or top soil and fertility it carries to drop out and be harvested within or beside the shelterbelt—which can then support greater health and growth of the shelterbelt and that which it protects by deflecting the strongest winds over a downwind garden, orchard, pasture, playground, road, or home.
The resulting snowdrift of accumulating snow around the trees of a well-designed windbreak/shelterbelt, then melts—more than doubling the annual moisture available to the vegetation. Furthermore, the reduced wind speeds reduce water loss to evaporation, both within, and downwind of, the shelterbelt. And evaporative water loss is reduced still more within in the shade of a shelterbelt – most notable where the hot afternoon sun is shaded out (see the Sun & Shade Trap examples in chapter 4 of Rainwater Harvesting for Drylands and Beyond, Volume 1, 3rd Edition).
But if a windbreak/shelterbelt is too dense, or incorrectly spaced from that which it is trying to protect, it could produce eddy currents that form a snowdrift where you don’t want one, such as atop your house, road, or driveway.
Vegetation and built structures can also be arranged to enhance/increase air flow for passive cooling and ventilation. This consumes no power, nor the water consumed in the generation of electricity or production of fossil fuels.
Note that the interior ventilation is greatly enhanced with more than one wall opening. All other things being equal (wind direction, vegetation, and so forth), the top example with only one opening will be cave-like, with less ventilation, compared to the bottom example. Reproduced with permission from Rainwater Harvesting for Drylands and Beyond, Volume 1, 3rd Edition. Illustration by Joe Marshall
Additional snow-harvesting strategies
- Diverting and harvesting snow melt with snow berms – see chapter 9 of Rainwater Harvesting for Drylands and Beyond, Volume 2, 2nd Edition
- Untrampled snow in the built environment showing us unused paved areas that can be depaved with green infrastructure, such as treed rain gardens, and brought back to life – see chapter 8 of Rainwater Harvesting for Drylands and Beyond, Volume 2, 2nd Edition
Missed opportunity to harvest snow melt
Roof downspout pipe (above orange cone) directs rainwater and icy snow melt over the sidewalk, under bike racks, and then into the street.
Switch the location of the tree with that of the bike racks, and more of the water and ice would be absorbed by the tree and its soil —reducing hazards for all, while irrigating the tree for free.
Photo: Brad Lancaster
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Volume 2
In Volume 2 see the Harvesting Windswept Snow case study in chapter 3 and Snow Diversion Berms case study in chapter 9