• Last month, I wrote about San Francisco's great rain garden/bio-retention basin project. Strategically placed sunken curb cuts, swales or park features collect stormwater and let it filter into the ground, reducing the pressure on overwhelmed storm drains and sewers.

  • Laurie Lauria and I spent last week moving out of San Francisco up to Napa, California, dodging the raindrops and taking advantage of a few dry days in this remarkably stormy winter — weather that makes this a perfect time to talk about the need to capture rainwater and protect overwhelmed urban sewer systems.

  • Climate change is going just as badly for cities as we have been warned it would. Extreme weather is increasingly common and severe globally. Australian cities have endured a number of recent disastrous events. It’ll get worse, too. The Intergovernmental Panel on Climate Change (IPCC) fact sheet outlining impacts on human settlements is a very sobering read.

  • I am a hydrologist who sometimes works in remote areas, so interpreting weather data and forecast uncertainty is always part of my planning. As someone who once nearly drowned while crossing a flooded river where I shouldn’t have, I am also acutely conscious of the extreme human vulnerability stemming from not knowing exactly where and when a flood will strike.

  • Andrea Tavera, a former University of Oklahoma graduate student, used Innovyze drainage design software to promote LID-based, green infrastructure design in hopes of resolving Oklahoma’s two greatest drainage challenges caused by stormwater runoff: excessive flooding and pollution. 

  • Floods are complex events, and they are about more than just heavy rain. Each community has its own unique geography and climate that can exacerbate flooding, so preparing to deal with future floods has to be tailored to the community. Recent floods provide case studies that can help cities everywhere manage the increasing risk.

  • Flash flooding is a specific type of flooding that occurs in a short time frame after a precipitation event — generally less than six hours. It often is caused by heavy or excessive rainfall and happens in areas near rivers or lakes, but it also can happen in places with no waterbodies nearby.

  • In 2019, researchers at the U.S. GAO investigated climate-related risks at the 1,571 most polluted properties in the country, also known as Superfund sites on the federal National Priorities List. They found an alarming 60% were in locations at risk of climate-related events, including wildfires and flooding. As troubling as those numbers sound, our research shows that that’s just the proverbial tip of the iceberg.

  • Although floods are a natural occurrence, human-caused climate change is making severe flooding events like this more common. In mountainous regions, three effects of climate change in particular are creating higher flood risks: more intense precipitation, shifting snow and rain patterns and the effects of wildfires on the landscape.

  • WaterNow’s Project Accelerator provides bandwidth and support to help communities get these types of projects off the ground. Open to cities, towns, utilities, and other public entities with responsibility for drinking water, wastewater, and stormwater, the Accelerator provides selected projects with about 250 hours of pro-bono support.



Clara's oil and grit chamber slows stormwater as it flows in, allowing pollutants to separate from the water by gravity.