HighPressure

Just a couple of days ago Michael didn't even exist, I don't know how rare it is for Hurricanes to form so late, and grow so quickly, he was a Cat1 yesterday, a Cat2 on last pass and as others have stated could hit as a Cat4 in less than 24hrs. I am no expert but watching these form this year via NHC says this one is unusual?

Humans are not responsible for climate change, it is a fact that the planets climate has constantly changed over time immemorial. The Doomsday book shows vinyards as far north as York in the UK indicating that temperatures were warmer a millennia ago. The question is, are humans helping that change? I don't know, I don't think anyone really knows, but for me the question is should be take the risk? My answer is No, we don't need to pollute so why do it. Its interesting the diseal car was seen as the answer to lower Co2 emissions, and petrol seen as the enemy, and now we have completely reversed that? Our own government is worried about making less cars in the wake of BREXIT, it wants us to buy more of them? They want to build a 3rd runaway at Heathrow, these are all counter to today's IPCC message. It comes down to will greed spell the end of humans on Earth? Probably! The Earth will of course be fine as Mother Nature will simply cleanse the place when we have gone..

From what I can see Thames are reporting @80% which isn't bad and comparable with previous years. They certainly have questions to answer on the supply side of things, as the network simply can't carry enough of the product on high demand, which is their problem not ours. Their luck is all due to last winter, had it of been dry they would not have been the groundwater or river flows there to sustain abstraction.

Not sure where to post this, but the title does have moan in it, so must be close enough. Can Netwether please replace that 'Feels Like' temp shown on the 10 day forecast to something closer to the actual predicted temp. For me today says 'Feels Like' 28oC about 8 degrees off reality - it drives me mad

I would not be so sure about the water shortage situation, too early for the major water companies to own up. In 1976 it was government owned, which is a whole different ball game to companies protecting billions of profits and share prices. Thames water are struggling to meet daily demand, they have low pressures and no waters across the network, their twitter is full of apologies. That shows the system is inadequate to cope with maximum demand, no matter how much storage they have. They will be crossing their fingers and toes that the rains come before September, otherwise there will be hose pipe bans. I have no sympathy for them at all, I cannot take profit unless I can supply my product, and I don't see why without any real engineering issues why we have to suffer for water companies to fill their pockets. Dubai / Saudi Arabia etc do not run out of water ..

Rain now will do little if anything to replenish stocks, unless its a sustained wet period. Groundwater levels only recover during the winter and early Spring months, this is because almost all the rain that falls is lost to either evaporation or due to the hard ground will appear in rivers as runoff. The type of rain you get (I know I sound like British Rail) is also an important factor, sudden downpours, although they will stop immediate demand dead in its tracks in that area, can actually be counter productive. The ground has picked up so much particulate matter, that any runoff into rivers causes the (DO) oxygen levels to plummet, the fish die, the water is almost untreatable, and can cause any abstraction taking place to be stopped. There is even a special boat known as a bubbler that works the Thames when needed which simply introduces oxygen bubbles into the water to oxygenate the river.

I can't talk for other areas. and I have been out of the industry for 10 years. As for London, a lot of investment went into modernisation after privatisation, it simply had too, and it was quite lucrative for the companies. Things such as K factors, and leakage targets played a big role in the amount of investment that went in. To give you one example Hampton WTW was still steam powered until 1982 and it took 200 people to run the plant, within 10 yrs or privatisation, it could be run with just 6 people. A huge project on the London Water Ring Main (which I was part of) was undertaken, and treatment works were uprated, however there was very little increase in stored water, which was a political hot potato due to leakage. The argument being you don't need more storage is you are losing 20% of what you already produce. There was no real increase in total capacity maybe even a decrease in capacity, although water transfer between internal areas was improved.

I am not sure we ever used the term drought at Thames with any real meaning. Its pretty much irrelevant, other than it will give companies more leeway to issue restrictions. There are many issues at play which cause problems with supply, yes peak times are more challenging because the longer it stays dry the more water people put on their gardens, this is why you get lower pressures in the evening. A pipe can only take so much water at (x) pressure, water may still not reach the end of the main even if the maximum amount is going in at source. As said previously as a storage reservoir drops so does its head pressure and thus flow to a treatment works, once you have a valve 100% open you are totally at the mercy of the level feeding you. Another factor which can cause serious problems is algae in the reservoirs, this causes primary filters to clog quicker requiring more frequent back washing. The number of filters online at anytime will have a direct effect on output. Water is drawn off open storage reservoirs at a point below the surface depending on quality, the lower a level goes, and stronger the sun the harder it is to find the quality you need. Shallow reservoirs are a waste of time at this time. All of this is set against daily demand which can be 20% above the average, the shorter nights (the recovery period) mean you have to pump as much as you can to restore levels for the early morning start. This puts the system at risk of burst mains, and that will usually occur just before dawn. It is one huge balancing act, that just like the titanic will sink if there is a prolonged period of dry weather. Metropolitan areas will be looking at the clock awaiting the end of school term, as usually means a 10% drop in overall demand as people go on holiday. Groundwater areas often require support from river source supplies to suppliment them as even with a fully working borehole it cannot yield anymore than its maximum, this puts even more strain on the system.

It was good to start with, a huge amount of good work was done between 89-95, then the greed set in, cuts were made where they should not have been. Profit was gained at the expence of the truth, and risk assessments were fudged. One of the reasons I left the industry, I simply had too many run ins especially regarding leakage which was the big topic of the time..

You can bet the water companies will be panicking, Profit versus Risk probability is the key calculation. From a technical perspective there is no need for any water shortage in the UK. It has to be remembered that the water companies combined take billions in profits each year, that is calculated against % risk. If there were to be severe water shortages, there a few MD's who will be looking for employment elsewhere.

Peak Demand time, a summer evening outside the City..

Its amazing what you can do online these days: https://www.gov.uk/guidance/apply-for-a-drought-order-or-emergency-drought-order This is what water companies do when they want to impose restrictions. This for Thames water will also allow them to abstract more water allowing rivers flows to decrease to their minimum which for Thames is measured at Teddington weir.

Hampton the 2nd largest Works has 2 x 100" tunnels supplying it, they will lose head as the storage reservoirs drop in level, the input to the works struggles to keep pace, this causes the output to drop from the works, you then struggle to retrieve potable water reservoirs at night, often bursting mains in an effort to do so. You tend to get a knock on effect..

There sure is lot a difference, its all down to resource management and investment in the system. I have been out of the water industry for 10yrs now but did work through the 1990, 95, and 2003 summers at Thames water. If anyone is actually interested I can tell you what actually happens in these situations and how they are managed. I won't bore you with the many stories, but I was at the sharp end. London they say has 100 days of stored supplies in its storage reservoirs to the west and North East London, with around 10% of its daily supply coming from ground water mainly in Kent. The problem with having a theoretical 100 day supply (@200,000 ml) is you have to get it out of the reservoir, treat it and then supply it. Anything less than 75% full starts to give real issues. As I say I can only speak for London, but if anyone does want to know anything I am happy to answer.

Everything is white, not a lot of depth, probably an inch maybe 2 on the flat but its drifting, we seem in a perpetual semi blizzard situation..

The snow doesn't seem to want to stop here in Sevenoaks, its been constant for the last few hours, and that blob over the estuary looks ominous??

I do indeed, I drove back from Surrey this afternoon, and it went from predominantly green to white between Jnc 7 and Jnc 5 of the M25. I guess this stuff must be heading your way?

We have semi blizzard conditions here on the North Downs, and even drifting snow.

Sevenoaks North Downs, we are showing current temp of 6.4c, it was 13.1c on Sheerness beach this afternoon, a coat not really needed in the almost warn sunshine.

My weather station is predicting rain, I think you are being optimisic?

Still a tad below zero here but slowly ice is starting to slide on my security cameras, so the show is over, bring on spring and some bloody warmth

That is enough snow, now when is the 1st warm spring day

Stopped snowing here in Sevenoaks, but what I want to know is where did all that snow go that fell for 2 hours or so? There is none on my car, and no more on my patio, has one of you got my snow piled up against your house

Yep Bulls eye

I am on Jnc 5 of the M25 just north of Sevenoaks, we have had moderate snow for the past hour, so I suspect Biggin is getting it too..