Introduction: ukuGalesha for a Circular Economy

1. Water and Circular Economy

The current water crisis is one of the most significant challenges of our time. Water challenges are particularly salient in urban areas, where more than half the global population lives for the first time in history. The worldwide urban population is estimated to nearly double by 2050 ⁠, which has profound implications for urban water demand. Presently at 15–20 percent of global water consumption, urban demand is set to rise to 30 percent. Increasing urban water, use will also lead to more wastewater and water pollution. Climate change further exacerbates pre-existing water stresses and is already having a measurable effect on the urban water cycle ⁠— altering the amount, distribution, timing, and quality of available water.

Circular Economy principles have emerged as a response to the current unsustainable linear model of “take, make, consume, and waste.” Yet so far, the water sector has not been systematically included in high-level circular economy strategy discussions. In practical terms, a circular approach designs products that reduce pressure on natural resources and minimise waste. Circular economy principles offer an opportunity to recognise and capture the full value of water (as a service, an input to processes, a source of energy and a carrier of nutrients and other materials).

Rethinking urban water through the circular economy and resilience lenses offers an opportunity to tackle all these challenges by providing a systemic and transformative approach to delivering water supply and sanitation services in a more sustainable, inclusive, efficient, and resilient way.

(The World Bank, 2021)

Watch the YouTube Video case study of Vitens NV that is a company in the drinking water industry that innovatively focused on the implementation of circular economy.

2. Soil Moisture

Soil moisture is difficult to define because it means different things in different disciplines. For example, a farmer’s concept of soil moisture is different from that of a water resource manager or a weather forecaster. Generally, however, soil moisture is the water that is held in the spaces between soil particles. Surface soil moisture is the water that is in the upper 10 cm of soil, whereas root zone soil moisture is the water that is available to plants, which is generally considered to be in the upper 200 cm of soil.

  • Water contained in the soil is called soil moisture.
  • The water is held within soil pores. The soil moisture is the key factor in determining how the soil of the region supports vegetation and crops.
  • If the moisture content of the soil is optimum for plant growth, the plant can readily absorb soil water.
  • Not all water held in the soil is readily available to the plants.
  • Much of the water remains in the soil as a thin film.
  • Soil water dissolves salts and makes up the soil solution, which is very important as the medium for the supply of nutrients to growing plants.

Rainwater Harvesting

Water harvesting by nature was a key factor in where villages were located. Village homesteads would usually face east and be sited to capture the early sun. They were also a short walk from a spring for drinking water from which cattle were excluded. Farmers would also prepare their lands in ways that captured moisture for easy ploughing and to hold soil moisture for germination.

In general, water harvesting is the activity of direct collection of rainwater. The rainwater collected can be stored for direct use or can be recharged into the groundwater. Rain is the first form of water that we know in the hydrological cycle, hence is a primary source of water for us.

Click below to read more about Rainwater Harvesting Practices on the Amanzi [water] for Food website. There are various flyers and videos available that can be utilised as teaching resources.