Life is an ultramarathon

To content | To menu | To search

Keyword - water

Entries feed - Comments feed

Thursday, April 26 2012


I know it might seem odd to some, but despite the frequent overcast London sky, it doesn't rain that much here. So much so that hosepipes are already banned and probably will be for the entire summer, if not until Christmas! It's OK, though, worse comes to worse I can use my purifier to get water straight from the Thames rather than from Thames Water...

But the most paradoxical is probably that following the heavy rain for the last couple of days, flood warnings have been issued in drought areas, which will nevertheless stay in drought...

Ultra lack of rain

Sunday, July 10 2011

Thames 2 - Julien 0

Thames Barrier at 4am.

Second time unlucky... But whereas last year was a disaster, this year was at least half-decent. I completed nearly 5 marathons out of 7.

Tower Bridge.


Things went generally as planned until Staines, where I pulled out last year. I had my first hard time "only" a bit before Windsor. Nothing alarming, a bit of time lost, but I managed to pick up the pace until Bourne End. I could see it would be a difficult one, but to keep hope, I decided to focus on getting to Oxford, and think about the source later

A new landmark has emerged since last year: The Shard.

Battersea power station.

The night

From 5pm, I could see all the boats stopping for the night, their occupants having chilled out apéritif and starting barbecues. It was hard to see that, while knowing I would have to go through the night. And indeed the night was pretty difficult. I was not only feeling rather chilly given the humidity near the Thames, but I also wanted to sleep all the time (some would say, as usual). A big surprise at Henley, the Regatta parties were going on next to the Thames. One kilometre of loud music and colourful lights, walking amongst thousands of drunken people in rowing blazers, after hours on my own in the dark. Surreal. A bit later, I had a quick nap on my backpack mat, wrapped in my survival blanket, in a effort to relieve me from both the cold and the tiredness. Not sure it worked out.

Sunrise near Sonning Bridge.


As the sun rose, I picked up speed, but I carried on losing time on schedule at a rate of about an hour per half-marathon. Partly due to my running speed, and partly due to longer breaks than planned. I even managed to get a bit lost in one of the three hilly sections of the course, as the path leaves the Thames for a few kilometres.
The path was certainly less and less busy as I moved upstream, and some long monotonous and lonely sections felt hard on the mental side. I finally reached Oxford, a fundamental milestone in my mind at nearly 9pm, 10 hours behind schedule. I calculated that I wouldn't make it to the source before Sunday night, and decided to give up.

Speed (km/h): planned (blue), actual (red), with "planned" rest time removed (green).

Things that went well
  • Food was well chosen, and the pre-packed mini-meal concept developed with Leo worked well.
  • Water filtering worked as planned. I had a short anxious moment, as I was pumping when a boat came passed. The water turned cloudy with the turmoil, and the filter clogged up nearly instantaneously. I followed the on-field cleaning procedure to remove the silt, and the water flew normally again. Pfff. In total, I drank 11 litres of purified Thames Water for 28 pit stops.
  • Recovery was surprisingly quick.

Thames Water inlet. Where do you think your tap water comes from?

Things that could be improved
  • Blisters under the feet. As I carried two spare pairs of socks, a change half-way might have helped.
  • Chaffing. I could have sorted out something with the Nok cream I carried.
Things that went wrong
  • Sleepiness at night, could be managed with a caffeine-based product and an even stricter sleeping pattern on the week before.
  • A light waterproof jacket would have been useful to insulate me against humidity during the night.
  • Book more time off, to remove completely the time constraint.

A sign I've seen countless times...

A third attempt?

My mind has slowly drifted on that matter:
Saturday: I'm happy about what I've achieved today. I won't try again.
Sunday: Reaching Oxford is good, but it would have been better to finish. I might run the remaining section on its own one day.
Monday: Why didn't I carry on? I might try again, but maybe with support.
Tuesday: I'm so stupid I stopped. I should try again solo and unsupported.
Wednesday: Why the f*** stopping "so close" to the end? I should try again in September.

I certainly gained a knowledge of the challenge which should allow me to complete it on another attempt. But it's a big commitment in terms of preparation. We'll see.

Should I stay or should I go? A recurrent question.

A big thank to all of you who supported me. I'm sorry I didn't make it to the source, but solo and unsupported is mentally very hard on such a distance.

Ultra river

Thursday, June 23 2011

It's all about water

On Saturday, I ran my last long training session, a nice 64km on the Thames Path. Despite my muscles being relatively tired, the pace was adequate, and most importantly, I felt generally strong.

I was greeted by a rather powerful thundery shower from the start, leaving me soaked for the remaining 6 hours. To make sure I didn't dry up on my way back, a spring tide forced me to run in the overflowing Thames.

It was also an opportunity to test the MSR SweetWater filter in real conditions. It took me about 10 minutes to filter 2.75L of water, including unpacking, setting up, and repacking. In terms of taste, let's face it, it's like drinking from a swimming pool, but it's reassuring in a way. I hadn't intended to use my water bladder, but the provided filter adapter just happens to fit well on it, and the refilling worked pretty well. In the light of this experiment, I've decided to take a water bladder and a bottle (for various additives such as rehydration sachets) on the TSQ. With 3L of water, I can run up to 4 hours if it's hot, and more during the night. I guess it's a matter of trading off between the the time to filter, and the water weight to be carried.

All in all, the water element was rather keen on communing, with or without my consent, which is a good omen.

Now, it's relative rest, increased nutrition and hydration for the next 7 days.

Ultra water power

Wednesday, June 1 2011

MSR SweetWater Purifier

I have finally decided to buy an MSR SweetWater purifier, hoping to increase my water consumption on the run. Indeed, the all-in-one bottles previously tested involve squeezing and sucking hard on the bottle, which has been proven rather irritating after a while. With a pump-based system, once the water has been purified and transferred into a regular container, drinking should be effortless.

The MSR SweetWater Purifier works in four stages:
  • Stainless steel prefilter to avoid clogging by larger particles
  • Silica depth microfilter against protozoa and bacteria
  • Activated carbon against chemicals (and foul taste)
  • Sodium Hypochlorite (ie. bleach) against viruses (and any filter-dodging bacteria)
MSR SweetWater Purifier
MSR SweetWater Purifier

As you can see from the picture, it is more fiddly than the all-in-one bottles. At 400g, it is significantly heavier too. The water is pumped mechanically through the prefilter and the intake hose, then passes through the main microfilter/carbon and gets out into another hose which can be connected to a container. Sodium Hypochlorite is added later, with a 5 minutes dwell time. If there wasn't a need for chemical addition, I would definitely try to hook up permanently the output hose onto a hydration bladder. In this case, I wouldn't even need to take off the bag to pump water in. But how can I easily add the bleach? I was thinking to use a syringe/needle, but all that gets very fiddly. Suggestions welcome!

As for the speed, I managed to filter tab water at 1.5L/min, but it'll be slower with more turbid water. After bleaching, the water didn't taste much of chlorine, which is definitely a big bonus.

Ultra pump

Thursday, May 26 2011

Chemical water purification

During last year's quest to water purification, I mostly looked at microfiltering options, neglecting chemical and UV methods. I've not looked properly into UV yet because of the need for batteries, but I have dug further into chemical water treatment. There is actually a whole range of products on the market, based on no less than 5 different chemicals: It is rather difficult to judge which one is best. And as you can see, the type of chemical seems highly dependent on variable country regulations. Since LifeSystems sell both Chlorine and Chlorine dioxyde on the same market, you would expect them to clarify this. Well, it's not very conclusive:

Chlorine is the most widely used disinfectant.
Chlorine Dioxide is the most effective disinfectant.


Whilst checking the product differences between countries, I've also noticed a bit of confusion around the Katadyn MyBottle capabilities. There is a significant difference between the fact sheets on the American and on the European websites. The European one features a single bottle called "MyBottle", eliminating protozoa, bacteria and viruses with "ViruPur". This is the one I bought. The American one however, features two bottles: "MyBottle Purifier" and "MyBottle Microfilter" (*). The former eliminates viruses with "ViruStat", but the latter does not. Problem: the latter looks really similar to the European one, which is supposed to filter viruses! All this starts to look rather dodgy to me...

Reading the product manuals is rather off-putting. For example, the MSR Purifier Solution manual starts well with:

Harmful if swallowed.

And carries on with a lot of warnings like this:

This pesticide is toxic to fish and aquatic organisms.

But my favourite is:

If swallowed:
* Call Poison Control Center or doctor immediately for treatment advice.

This is supposed to purify filthy water into "drinkable" water. How the hell are you supposed to use it if you cannot swallow it?

There is also a variety of chemicals to remove the taste of chlorine/iodine, but it starts to make the whole process a bit fiddly on the run: pump 1 minute to get your liter of water, add chlorine, wait 5 minutes, add neutraliser, wait 3 minutes, and finally drink.

I guess Chlorine Dioxide might be the best choice, as it appears to have less after-taste than the others, thus avoiding the neutralisation stage. Silver ions are tasteless, but apparently more for conservation than actual treatment.

Ultra chemical water...

(*) Whose names are by the way somehow consistent with the MSR terminology, with their "SweetWater Microfilter" and "SweetWater Purifier". Only the latter eliminates viruses.

Sunday, July 25 2010

Ultimate triathlon and Thames water

I've recently come across Charlie Wittmack's challenge, The World Triathlon, which consists in none less than swimming down the whole Thames and cross the English Channel (275 miles / 443km), cycle to China (9,000 miles / 14,500km), before running to the summit of mount Everest (950 miles / 1,500km).

As you can imagine, this is not going to be trivial, but it's interesting to note that the first issue faced by Charlie was to inadvertently drink a sip of the Thames water and consequently falling violently ill! Luckily Charlie is now fine again and should be swimming in London tomorrow.

Ultra ultra triathlon

Thursday, July 15 2010

Thames 1 - Julien 0


As you probably know I've attempted the Thames Sources Quest, 296km from the Thames Barrier to its Source last week-end.

Thames Barrier
Thames Barrier at 4am

I left on Friday at 4am, carrying a bag loaded with 4kg of food (13,000KCal), 3kg of water for the first 50km of non-tidal Thames, and not much else.

Canary Wharf
Canary Wharf at 4:30am

The London section was a bit hectic, as the Greenwich foot tunnel was closed (just for the one night I was running...) and I had to follow the South Bank that I hadn't recce'd. Also, a number of the path sections are on private grounds and closed at "night", that is until 7am. I got lost a few times and made a lot of detours. Sometimes unexpectedly bumping into known places (see below). But London before 7am is relatively quiet for a change, with only a few dog walkers and (rather fast) runners.

Tower Bridge
Tower Bridge

The Circle
Known location :)


Battersea power station

Things went relatively well until Hammersmith, where I started to feel a bit weak, and even had minor cramps in the quads. Maybe I didn't eat enough, as my stomach was not in a great mood? I decided to push until Richmond anyway (44km) to complete the first marathon and have a brief rest there. Unfortunately, I had to stop a few kilometres short from Richmond to sit down and I even fell asleep... until a dog woke me up by licking my face :) I had a bit of food and felt better, ran to Richmond, sat down and ate again. Things went a bit better from Richmond to Hampton Court (57km).

As I reached Hampton Court at about 12 noon, the sun was getting pretty hot (30°C, native Englishmen would say scorching), and again I was running very little. Walking more and more, and even sitting down from time to time. Passed Shepperton Lock (67km), I was walking most of the time. The day was gorgeous though, and the Thames looked great. I really felt like diving in.

The Thames near Staines

I had my first sip of purified water from the Thames just passed Teddington Lock as my spring water bottles ran out. I have to say the water didn't look amazing at that point, but it became much better upstream from Hampton. The purified water tasted good, but felt a bit heavy. I'm not sure whether it's the nature of the Thames Water, the iodine or my stomach. In the end, it was easy to integrate the Aquapure Traveller 15 minutes dwell time into my rythme: I just had to count three periods of 4 minutes run + 1 minute walk. I thought I drank a lot at the time, although my log sheet later told me I only took water 4 times, ie. only 2 litres in 7 hours... I also passed water a total of 4 times if you're interested, but only once in these last 7 hours...

Aquapure Traveller
Sampling the Thames Water

Considering that I hadn't enjoyed much of my day, that I was walking most of the time and stopping often, that I was already late by over 4 hours and therefore that I wouldn't be able to reach the source, I decided to give up at Staines (76km). I also had the PTL at the back of my mind and didn't want to jeopardise my and Leo's chances on a project that I would not be able to complete anyway. Essentially, during and after this attempt, I felt like I had run twice as much... (which would still be only half of the TSQ).

As for the "guess my time" competition, John Kynaston got the closest bet with a DNF at 200.5km. Yannick gets the best water in and water out guesses. Congratulations!


There are numerous reasons, which combined together led me to give up. First of all, I was not well prepared physically and mentally. Especially on the latter, I had done a lot of visualization in the past, but not close enough to the actual attempt. Secondly, with the PTL only one and a half month later, I was not properly focused on the Thames.

And there are a lot of other minor reasons, such as the heat, a poor nutrition during the first 4 hours and a poor hydration towards the end. Also, running by Hammersmith (where I live and train) after 35km is a bit demotivating, as it essentially felt like I hadn't covered any ground when reaching the first marathon. More generally I've been relatively tired over the last few months for various reasons. Finally, I might no be such a good runner on flat courses, as I found the UTMB flat sections boring for example?

I also might have been overestimating myself. Thinking I would be able to run any distance at any time, without much training... It might be true up to a marathon distance, but certainly not much further.

Anyway, this is a good wake up call before the PTL!

I think the TSQ remains a great challenge, and I still want to complete it one day. Next year maybe...

Ultra fiasco

Wednesday, July 7 2010

Thames water purification on the run: a solution

After a brief survey of what nasties are waiting for me in the Thames, I tried to find a suitable water purification system. And it's not easy. Ideally, it would be a all-in-one integrated system based on a hydration bladder with two pipes: one regular pipe for drinking and another connected to a pump+microfilter that could be stored in the backpack side nets. No need for extra chemical and no need to remove the bag to either drink or re-fill. I actually know of one such system, the Lifesaver Hydrocarry, which is only available to the military. Otherwise, you would have to build it yourself (*).

Back to reality now. I've considered the following purification systems:

System Main Viruses Carbon Flow Weight


L/min g


Katadyn MyBottle + ViruPur 0.3 yes yes 0.2 260
PureHydration Aquapure Traveller 0.2 yes yes ? 128
PureHydration PureLink (inline) 0.2 yes yes ? 120
LifeSaver Bottle 0.02 yes yes 2.5 635

Ceramic only

MSR Hyperflow microfilter 0.2 no no 3 209
Katadyn Mini 0.2 no no 0.5 210

Ceramic + carbon

MSR Sweetwater microfilter 0.2 no yes 1.25 320
Katadyn Hiker 0.3 no yes 1 310
MSR Sweetwater purifier 0.2 yes (chem.) yes 1.25 397
Katadyn Vario EU 0.3 no yes 1 460

There are a lot of contradictory opinions on all filters. I need to make a few trade-offs on weight, what is filtered, and the flow. I've decided to make no compromise on water quality and therefore filter everything, which is debatable, since the viral risk is relatively low in the Thames. This means I need a 0.2 to 0.3 micron filter for protozoa and bacteria (every system has got that), activated carbon filter for chemicals and taste, and some form of virus elimination. I didn't want to put extra chemical after filtration, which makes the whole process a bit fiddly.
Besides, all the systems with a nominal flow under 1.5L/min put me off a bit. Indeed, this is the highest achievable flow and could be much worse depending on turbidity. Users have reported flows down to 0.2L/min with some systems, ie. 5 minutes to fill in 1 litre. This is not suitable on the run.

So I was essentially left with the all-in-one bottle systems. With such systems the flow is less of an issue, as the filtration happens whilst drinking, ie. during the run and not during the filling-in breaks.

I had decided to get sponsored for the purification system. This decision was not only driven by the financial aspect, it's also to make sure that the system is actually going to work. Manufacturers want good publicity, not the story of a runner who either had to stop due to a filter malfunction or even got poisoned using their product. So I assumed they would accept only if they trust their system to filter the Thames water appropriately. I've contacted the three short-listed manufacturers. Two of them didn't bother to reply and the third promptly accepted to sponsor my challenge, but then didn't follow up for some reason.

Therefore I've decided to buy the Katadyn Mybottle Purifier and the PureHydration Aquapure Traveller, the LifeSaver being much heavier and bulkier. My original idea was to carry both, as if one system fails during the run for whatever reason, I won't be stuck with no water. Given the weight and volume they take, I might actually take only one in the end. In order to choose, I've tested both of them using some fresh Round Pond water from central London. I have to say it looks rather green at the moment and the dense population of ducks/swans/geese doesn't help with the water colour.

Round Pond
The Round Pond during the water sampling

I've put side-by-side the untreated water and the two others. The untreated water had a green-yellowish taint, but didn't actually smell. Both purified waters looked clear. The main difference between the two systems is how they eliminate viruses. The MyBottle relies on eletrokinetic filtering, whereas the Traveller is iodine-based. This technical difference leads to a number of very practical implications:

Weight 260g 128g
Flow very slow slow but easier
Taste clear iodine
Delay instantaneous 15 min iodine dwell time

Obviously, the weight and flow are in favour of the Traveller, but I'm not sure I can see myself waiting and timing 15 minutes. Or maybe I can turn this downside into a feature by setting a routine: fill in, wait 15 minutes, drink half-a-liter during the next 15 minutes, repeat? As for the iodine taste, it can be removed using vitamin C, but I'm not sure how to do that in practice, as that would probably mean transfering the filtered water into another container.

Ultra water.

(*) This could be done rather cheaply using for example the Aquapure inline filter and a bladder, but you would face some watertightness issues when incorporating the second pipe in the bladder.

Tuesday, April 13 2010

Thames water purification on the run

As previously mentioned, one of the only source of water during the Thames Source Quest (TSQ) might be to drink from the Thames itself.

Ebullition would be the most radical method, but is not practical whilst running. Most commercially available portable water purification systems are based on microfiltration, which performs well against "big bugs" (protozoa and bacteria), but fails against viruses. I would need to use ultraviolet or chemical treatment to get rid of these nasty guys, most likely iodine. Remains the chemical pollution that might be solved partly with an activated carbon filter. I've contacted Thames Water to get more information on the exact nature and distribution of the pollution, but they tend to be very vague, only providing qualitative appreciations such as "bad", "good", "very good". If you have access to more accurate data, please let me know.

Here is my current plan for filtering:

PollutantExampleSize (microns)Solution
bacteriaE. Coli, Salmonella0.2-0.5microfiltering
virusesHepatitis A0.01 to 0.3iodine (or UV)
chemicalDDT, heavy metals-activated carbon
bad tastesilt
-activated carbon
vitamin C

As for the microfilter, I'm considering either the Katadyn Mini (18x8cm, 210g) or the Katadyn MyBottle (26x8cm, 260g). The latter is more practical and includes an activated carbon filter and iodine resin. But this all-in-one design is not suitable for turbid water, which might be the case of the Thames.
I've discovered much more recently the Lifesaver Bottle (30x9cm, 635g), which is claimed to filter at 15 nanometres (0.015 microns)! It would therefore remove all the viruses as well as the bacteria. Plus it's meant to work with muddy water. During one of his talks, the inventor actually filters Thames water (or so he says), with a few much more disgusting add-ons and drinks it. Convincing enough! The main drawback: it's three times as heavy as the Katadyn products.

One funny thing with most websites advertising portable filtering, is that all the "action" pictures seem to involve crystal-clear mountain lakes or springs from which I would drink straight away anyway...

Any comments?

Ultra purification.

(1) Strictly speaking a simple water filter is sufficient.

Thursday, February 11 2010

What does 'unsupported' mean?

As I start to plan more carefully the Thames Source Quest (TSQ), I'm wondering what approach to take in terms of support. Interesting definitions of 'unsupported' are provided on [1] and Fastest Known Time [2]. The main disagreement seems to be related to water supply.

This really means no external support at all from any human being and therefore carrying all the supplies the whole way, except what can be obtained from natural sources. Water should only be obtained from natural sources according to [2], but could be supplied externally according to [1]. That said, the definition of a 'natural source' of water is not as obvious as it seems. If a spring in the mountains is natural and a free tap next to a river lock is not, what about a pipe draining the water out of a spring? I would say natural, but I can understand some would disagree. Food could potentially be harvested from natural sources too [1].
[1] prohibits the usage of phone calls, but surprisingly reckons that being offered a shelter and water is acceptable. The position of [1] here lacks a bit of coherence and seems biased towards classifying the Marathon des Sables as unsupported, which I cannot agree with. With all due respect to the toughness of this race, I can hardly consider unsupported an event where tents, water and medical crew are waiting for you every night.
Furthermore, a valid issue pointed out by [1] is how to react to local by-passers offering water, food, shelter or whatever else. It would be rude to refuse...

This means that no support team is following the runner. However, it is possible to grab whatever is on the way, including buying in stores or hide supplies in advance [2] (as at least one team did during the PTL last year). This is what I've done (for the water only) during my solo London to Brighton run, and this is also the spirit of the PTL. Because nothing is black and white, [1] also differentiates between several forms of self-support, the most permissive one including a crew following loosely the runner. I'm not too interested in that, so I won't discuss it in more details.

A team is following the runner the whole way to provide food, drink, spare clothing and all other needs.

As a summary, I would consider 'unsupported' the following:
  • Water can be obtained from natural sources only, like [2].
  • Food must be carried or obtained from natural sources only, like [1].
  • Shelter must be carried (tent) or natural shelters must be used.
  • Phone calls are prohibited as they offer mental support, but sending out SMS about your progress is acceptable... as long as you don't read the answers :) .
In one sentence: take everything you want from the nature and give back everything you want to whomever you want. Now, this is only my definition. I'm not saying I'm going to run the TSQ unsupported as yet :) .

Open for debate.

Ultra unsupported
Powered by