Discussion Questions for Sandra Postel's Replenish

Replenish The Virtuous Cycle of Water and Prosperity

By Sandra Postel Discussion Questions: 1. For most of modern history we have relied on large dams, diversion canals, flood-control levees, and other impressive engineering works to meet our water challenges. These engineering solutions have yielded enormous benefits for society and the world economy. But Replenish makes the argument that to build resilience to the impacts of climate change, society will need to work more with nature, rather than against it – for example, by reactivating river floodplains to capture more floodwaters rather than relying so much on levees. It calls for more “ecoengineering solutions.” What do you think of this argument? What are some of the best examples to support (or negate) it?

2. Our personal water footprint refers to the water consumed to produce the food we eat, the energy we use, the material things we buy, and the water used at home for cooking, cleaning, and landscaping. Since water is finite, shrinking humanity’s water footprint is critical to building water security. How can we do this without compromising human health and well-being?

3. The Colorado River rarely reaches the sea anymore. Why is this? Replenish includes a chapter on the US-Mexico initiative to restore a portion of the desiccated Colorado River Delta. What will it take for this initiative to succeed over the long term? Is the investment worth making? What lessons might we take from the Colorado River story going forward?

4. Why did China launch an initiative called “Sponge Cities?” What does this phrase refer to, and what does the initiative aim to do?

5. Algal blooms are a growing problem in the world’s rivers, lakes and estuaries.

In 2014, an algal bloom in Lake Erie forced Toledo, Ohio, to temporarily shut down its drinking water intake from the lake. What was the risk in drinking the

water? Why are algal blooms increasing around the world? And what might we, as a society, do to reduce them?

6. In recent years, parts of Australia, Canada, the United States, and other countries have experienced massive wildfires, which scientists predict will grow in size and number as global heating progresses. Why are these mega-fires a threat to drinking water quality, and what can be done to protect water sources from fire risks?

7. The United States has decoupled water use from economic growth, meaning that water use has declined even as the economy has grown. Why is this important? What were some of the key tools and policies that have allowed this to happen?

8. Soil is often missing from diagrams of the global water cycle, yet soils can theoretically hold eight times more water than all the world’s rivers combined.

Why has the water-holding capacity of soils decreased, and what can be done to rebuild this critical water reservoir?

9. The author of Replenish chose not to use the common phrase “water resources” in writing her book, though she writes extensively about rivers, streams, lakes and wetlands. Why do you think she might have consciously chosen to avoid this term?

10. Replenish makes the case that we will experience the impacts of climate change largely through the water cycle – for example, more numerous and/or severe rainstorms, floods, droughts, and algal blooms; as well as groundwater depletion and sea level rise. As a society, how do we prepare for these threats and build more resilience?