When a massive event center was being developed in Denver, planners had to contend with two existing 6-foot (1.8 meters) wide sewer pipes that emptied into the river, creating an unsightly dilemma.

Will Kenton is an expert on the economy and investing laws and regulations. He previously held senior editorial roles at Investopedia and Kapitall Wire and holds a MA in Economics from The New School ...

Will Kenton is an expert on the economy and investing laws and regulations. He previously held senior editorial roles at Investopedia and Kapitall Wire and holds a MA in Economics from The New School ...

We independently review everything we recommend. When you buy through our links, we may earn a commission. Learn more› By Thom Dunn Thom Dunn is a writer focusing on home heating and cooling. He once ...

Mike De Socio is a CNET contributor who writes about energy, personal finance, electric vehicles and climate change. He's also the author of the nonfiction book, "Morally Straight: How the Fight for ...