Water

To optimize water usage, we need to: 

  • reduce water demand through efficiency and conservation
  • reduce water losses in transport and distribution systems, including utility and building losses
  • recycle water appropriately and separately for drinking and irrigation
  • reuse sanitary gray water in local landscapes
  • make better and more efficient use of rainwater and natural filtration systems
  • increase water supply through desalinization
  • address climate change (global warming) 

Mandate regionally-appropriate landscaping and agriculture

  • Penalize, then ban, landscapes that consume excessive water in regions that are drought-prone or which receive their water from distant or threatened sources (aquifers, rivers, etc.)
  • Penalize, then ban, growing of water-intensive crops that consume excessive water in regions that are drought-prone or which receive their water from distant or threatened sources (aquifers, rivers, etc.)

Mandate water-efficient irrigation systems

  • Penalize, then ban, wasteful irrigation practices such as flood irrigation, over-watering, running sprinklers during the day, etc.

Recycle Water

  • Mandate gray-water recycling systems in all new commercial and residential buildings
  • Tax credits for investment in gray-water recycling systems

Renew the water infrastructure

  • Repair and replace aging water distribution infrastructure to minimize loss in the system “before the meter”. Use this as an opportunity to revolutionize the systems as listed above.

Make cities more porous

  • Incentivize paving systems that allow water to soak into the ground (e.g. pavers vs. concrete or asphalt) for commercial, residential, and municipal properties
  • Direct runoff into natural terrestrial areas that can use it — ponds, gardens, woodlands, etc.

Desalinate sea water

  • Divert excess renewable energy production into ecologically sensitive seawater desalination (as well as energy storage)

Discussion

Not only is climate change increasing water demand while threatening our sources of fresh water (snow and ice, surface water, aquifer renewal), but water pumping and distribution is a major consumer of energy, accounting for 4% of electrical usage. On the flip side, thermoelectric power generation (coal, gas, nuclear) is the largest consumer of water, substantially ahead of irrigation.

Unfortunately, much of the water exported by water utilities for consumption is wasted due to leakage in the transportation and distribution infrastructure. According to a 2016 report by the America Water Works Association (AWWA), and WaterWorld.com, real non-revenue water losses are huge, averaging 30-40%, while some systems can lose up to 70%. 

Climate change is increasing our water demand

Rising temperatures increase evaporation, drying the ground and forcing plants and animals –including food crops, landscapes, livestock, and people — to consume more water to stay hydrated and cool.

Climate change is reducing our fresh water supply

Warming temperatures are melting glaciers and snowpack worldwide. The Himalayas supply water to ⅓ of the world population in India, China, Pakistan, Afghanistan, Bangladesh, Nepal, Bhutan, Myanmar and others. The Andes supply water to much of the South American continent. The Rockies and Sierras supply western US and Canada. 

Lack of fresh water impacts agriculture, industry, recreation, and our energy supply. 

Water, Energy and Climate Change are Interwoven

As shown in the graphic above, a huge percentage of our water is either used or consumed in generating energy. It is drawn to generate steam, which drives turbines in coal, natural gas, and nuclear power plants. When there are shortages, these plants are forced to deactivate one or more of their turbines, reducing our energy supply. Much of this water is lost to evaporation. Although much of that water is returned to the environment, it is often warmed or polluted, harming wildlife and people.

On the other hand, a huge percentage of the power we generate is used to pump, heat, and process water! This circular relationship between energy and water is referred to as the Water-Energy Nexus, and is illustrated below. 

The Water-Energy Nexus

For more detail, Wikipedia has an excellent article explaining the Water-Energy Nexus. 

So energy, water, and climate change are inextricably interwoven. Reducing water consumption reduces energy consumption. Reducing energy consumption reduces water consumption, while mitigating the climate change that affects both water consumption and availability.