Each other. reporter: engineer christian nielsen is a strategic adviser to miami beach and one of the designers of copenhagen s climate resilient initiatives. this design-centric city of 1.4 million people is growing in population while adapting to climate risks. as nielsen shows us in st. anne s square. ten years ago, what did this look like? this area is the former lineup for the ferries going out of copenhagen. you would have one lane of parking, two lanes of driving traffic. more or less asphalt from facade to facade. reporter: now it s what he calls a cloud burst street. we chase the profile of the street to a v shape, and when the flood overloads the separate storm sewer systems, it goes to the street and flows into the green median, and from there it s diverted directly into the harbor. anne is with me now.