Created on 04/10/2019

As part of our campaign for better boaters' facilities, we promoted Kate Saffin's Great Big Boating Bog Survey earlier this year. Here she reports on its findings.

The Great Big Boating Bog Survey was a comprehensive questionnaire on toilets presented to boaters. It had six different routes through it (cassette, compost, incinerating, pump-out and two for those planning to start boating in the future), and received 1,700 responses. It was also unique in that it was entirely independent from any navigation authority, boating organisation and toilet manufacturer or supplier.

Boat toilet survey

The starting point for the survey came from my interest in composting toilets. I first researched and started composting in January 2014 when I was leaving a short-term mooring in London and would be exploring the capital's waterways. I found that all the reported horrors of life on a boat in London – being mugged, burgled or relieved of my bike – held far less terror than how on earth I was going to manage emptying the Porta Potti! Spare tanks could only be bought as part of a complete toilet, which seemed a terrible waste of money, so I started researching composting systems. My bedtime reading for several weeks was The Humanure Handbook by Joseph Jenkins – there were none of the online resources there are now. Five years on and waterless toilets have started to become almost mainstream. I thought it would be useful to do a survey on composting to establish a better picture of who was doing what, where and how. Canal & River Trust had carried out two such surveys, both of which I felt had methodological flaws. The results, which it has been kind enough to share with me, include many comments along the lines of 'you didn't include...' and 'I couldn't answer this because...'

I started to frame the survey and then realised that this would be an opportuniy to gain a wider picture. After all, composting wasn't the only type of new bog on boats – a lot was being written about incinerating loos. Having a good overview of the split between pump-out and portable chemical systems could also be useful as boaters are forever asking for more and better facilities. Finally, by including all users I could assess attitudes to the various available options.

Careful questioning

The survey ran over January and February of this year and achieved 1,700 responses, of which 1,525 could be included in the analysis (if they didn't answer 'what sort of toilet do you currently have?' they were excluded as that was the whole point of the survey). The survey was designed and run using Survey Monkey. This allowed me to develop a large-scale questionnaire with a number of different routes through that could handle several thousand replies. It was also affordable (I funded the project myself). However, it meant that participants would be self-selected and an online survey would always be favourable to those are confi dent and active with online engagement – thus there is bias. No statistical wizardry can claim that a certain group of boaters are more likely to like cassettes, or that all who compost are in a specific age group based on the results – they can only show the opinions and preferences of those who participated, not the wider boating community as a whole. I also knew that my interest and involvement in the composting toilets for boats groups would introduce an element of bias. I did my best to counter this by recruiting a panel of testers to provide ruthless feedback, undertaking three rounds of testing and promoting the survey via routes such as CRT's Boaters' Update and the IWA Bulletin as well as social media, to reach as wide an audience as possible.

Readable results

This isn't a scientific report so I have tried to keep it readable, limit detailed numbers and percentages, and just give a sense of the findings without drowning anybody in statistics. I've focussed on providing an overview of current options, satisfaction and trends, including the choices newer boaters are making and attitudes to different types of toilets. For the purpose of this article, I had to decide how to refer to compost/waterless/diverting toilets. This is because, in reality, there is no such thing as a composting loo. Just like with cassettes and pumpouts, there's a container to collect the waste which is then processed elsewhere. It's a system, not just a toilet. However, as compost and composting have become common terms, that's what I've settled on here. One day I'll convert the boating world to talking about dry or waterless toilets, which will hopefully get rid of the idea that a compost toilet performs some kind of magic – use it and compost will appear with just a sprinkle of sawdust! The picture of boating that this survey creates is based on those who are familiar with the internet and have the will to complete online surveys. There is broad range of age, with perhaps slightly more responding in the 46-64 range (52%) which probably reflects those comfortable with online activity rather than the real spread. The majority were boat-owners, with a good mix in terms of length of time boating, areas visited in the last year (East and West Midlands seemed to be the most popular), and with or without a mooring.

Delving into the data

Nearly half (47%) have a cassette or portable system of some kind, 35% a pump-out, and 16% a compost toilet. Eight (0.5%) said they had an incinerating toilet; however, on closer examination I discovered that one of these actually< had a compost loo but burns the contents once dry

Most are satisfied with their current loo (between 78% and 94% saying they were ‘very satisfied’ or ‘satisfied’); however, those with a compost system appear more likely to be ‘very satisfied’. [Note: excludes incinerating toilets as there were fewer than six responses.]

About a fifth of cassette and pump-out users are planning to change their toilet when they can. Very few of the compost group want to change but that is to be expected given that it is a relatively new type of system so most respondents will have made a positive choice to have one, rather than inheriting someone else's installation. Most (84%) aren't planning to replace their toilet in the near future. Of those who were, a quarter would choose 'like for like' and three-quarters a different system.

Taking it a little wider, I asked: If you are, or were, to consider changing your toilet, or were building a new boat, how would you rate the following options?

Cassette and compost led the field. There are differences between groups, as you would expect: cassette users aren't keen on pump-outs and vice versa. The compost group are firmly in favour of what they have (98%); cassette users were mostly in favour of what they have (80%) but with 30% keen to consider compost, and very few interested in pump-out or incinerating. The pump-out group aren't keen on cassette but a quarter would 'definitely consider' a compost toilet. Interestingly only half or fewer would definitely consider another pump-out, and those that did favoured a macerator over vacuflush or drop-through. In the 'definitely wouldn't consider' category, drop-through pump-outs led with just over half of respondents in any group ranking them the least desirable option. Incinerating toilets aren't far behind with just under half saying they 'definitely wouldn't consider' one. There are concerns about the cost of installation and running, the power demand, whether they are safe (likely to cause a fire), and the environmental impacts. Around 10% of those who commented had never heard of them but a handful (3%) would be interested to know more. About a third of both cassette and pump-out users wouldn't touch a compost toilet. Their concerns span from the size and cost of toilets, the space and time needed to fully compost waste, and beliefs that the toilet will smell and need a fan running all the time.

The numbers of respondents who are planning to boat are small (25) but they give an interesting glimpse into what future boaters might be wanting. For those planning to buy a boat in the next six months, a cassette or composting would be their ideal, while for those looking further ahead incinerating was in the lead.


There is still work to do on the analysis of the data (there are 3,100 comments alone on why users would or wouldn't consider each type of loo and 3,200 on the subject of facilities) but so far, the findings suggest that there is:

  • Increasing interest in compost toilets and composting, although there are concerns from both supporters and detractors about facilities to support fully composting
  • Possibly declining interest in pump-outs, especially drop-through models. Those who want a pump-out want a high-end installation such as a macerator
  • A very small proportion of incinerating boat loos, and these type of toilets currently attract considerable hostility. Interest is likely to growand they will appeal to those who want a very high-end system and have the power to support it.

Finally, a very big thank you to those who contributed.