What do heavier downpours have to do with anything? It’s all about volume. Combine population growth (which produces volume) with the 770 or so US cities that have combined sewer systems that take in stormwater, and you have serious volume problems any time it rains hard. In the US, the report states, “In the United States, the amount of precipitation falling in the heaviest 1 percent of rain events increased by 20 percent in the past century, while total precipitation increased by 7 percent. Over the last century, there was a 50 percent increase in the frequency of days with precipitation over 4 inches in the upper Midwest.” Already sewage overflows are much commoner than you’d think (see the EPA’s Combined Sewer Overflow site for exhaustive detail and a handy Combined Sewer System demographics map, though I’m puzzled by the “approximately 772 cities” - are they guessing?). And they will become commoner still. “Using 2.5 inches of precipitation in one day as the threshold for initiating a combined sewer overflow event, the frequency of these events in Chicago is expected to rise by 50 percent to 120 percent by the end of this century,302 posing further risks to drinking and recreational water quality.” That means that the $55 billion that the EPA estimates is needed to correct existing sewage overflows will be swamped and drowned by a much, much bigger number.

What’s the solution? I gave a talk last night to a packed Café Scientifique in Stockon-on-Tees, and was asked by the extremely engaged and nice audience the same question. “You’re not suggesting we rip out sewer systems and all have composting toilets, are you?” asked one man. No. Tinkering and some retrofitting and people who want to change their toilet systems, by going off-network or installing dry toilets or greywater filters: that’s all one part of the solution. The other is acknowledging the flaws in our existing system, which the Climate Change report has done, and then figuring out how to fund change, sensibly.

Things I learned at the conference:

From a urologist who is on the board of trustees: Thailand, he thinks, has the highest number of spinal injuries in the world and therefore huge issues with continence (peeing obviously becomes difficult when you’re para or quadraplegic). Why? Because mostly rural Thailand has more money these days and people are buying motorbikes. Add that to the fact that, as with many developing countries, road accidents are endemic, and you get hundreds of thousands of people coming off their “donorbikes” (as doctors call them: head injury deaths, which are common with bikes, leave organs intact enough for donation), and hundreds of thousands of spinal injuries.

From two Glaswegian family planning nurses (male; one with ponytail): no-one has ever defined female sexual dysfunction. There is a G-spot ie an area of extra-sensitive tissue in the anterior wall (I think) of the vagina, but thoughtless surgeons often remove it. Also, most stunningly, the contraceptive pill causes sexual dysfunction.

The prize-winning product of the conference was Shreddies, a line of lingerie which can filter flatulence, a serious, serious problem for anyone with IBS or Crohn’s disease. Or even vegetarians (I should know). The underwear - which looks great - passes odours through a carbon filter. Cool. The two Shreddies representatives on the exhibit stand were enthusiastic young women who showed no embarrassment about their product, as well they shouldn’t.