Dredging

[steelaway]

We were watching a boat cleaning up the canal in Burnley on the TV this morning. Good Lads

They mentioned that the canal was probable 6-8 ft deep when it was built, but now needs dredging.

It occurred to me, ignoring the fact that they have to find some where to to dump the spoil, is there any evidence that the silt on the bottom of industrial canals might be toxic in some way.

Could this be another reason why they hesitate to dredge many of our canals?

 

Alex

[Smelly]

I'm sure they treat the dredgings as toxic waste these days... Special dump and all that. I remember when they dredged the W&B a couple of years back they baged the dredgings; let them dry out and then put them on the back of a wagon for disposal.

[mykaskin]

We were watching a boat cleaning up the canal in Burnley on the TV this morning. Good Lads

They mentioned that the canal was probable 6-8 ft deep when it was built, but now needs dredging.

It occurred to me, ignoring the fact that they have to find some where to to dump the spoil, is there any evidence that the silt on the bottom of industrial canals might be toxic in some way.

Could this be another reason why they hesitate to dredge many of our canals?

 

Alex

 

It might be, so they have to test for it = money

Land fill tax = money

dredger = money

staff = money

admin = money

management = mo money

 

Maintance fund = NO money...

 

 

Mike

 

ps. I don't know the gauge the Leeds and Liverpool was built to, but I don't think it was ever that deep. Perhaps 4.5 or at best 5 ft.

Edited November 21, 2011 by mykaskin

[Catrin]

We were watching a boat cleaning up the canal in Burnley on the TV this morning. Good Lads

They mentioned that the canal was probable 6-8 ft deep when it was built, but now needs dredging.

It occurred to me, ignoring the fact that they have to find some where to to dump the spoil, is there any evidence that the silt on the bottom of industrial canals might be toxic in some way.

Could this be another reason why they hesitate to dredge many of our canals?

 

Alex

That is a very interesting point.

 

At the HNBOC meeting last year I remember Malcolm Braine showing some slides of what he described as "phosphorus gas" flowing down into some of the locks on the BCN back in the 1970s. It was a white cloudy gas, which looked heavier than air as it was flowing around the top gates and down into the bottom of the lock. I don't know much about this (any chemists out there?) but I do remember something about 'phossy jaw' as being an influence in the Bryant and May Match Girl Strike of 1888 (some little of what I retain of O Level History 40 years ago!).

Cath

[Chalky]

 

They mentioned that the canal was probable 6-8 ft deep when it was built, but now needs dredging.

 

 

When they dredged the Wharf at Fenny Compton (South Oxford) a couple of years ago I put the pole down to find how deep they'd gone. It was something like 7' - 8'. The depth now is about 3' - assuming that there's any water.

[furnessvale]

We were watching a boat cleaning up the canal in Burnley on the TV this morning. Good Lads

They mentioned that the canal was probable 6-8 ft deep when it was built, but now needs dredging.

It occurred to me, ignoring the fact that they have to find some where to to dump the spoil, is there any evidence that the silt on the bottom of industrial canals might be toxic in some way.

Could this be another reason why they hesitate to dredge many of our canals?

 

Alex

 

All dredgings have to be tested for heavy metals etc before disposal. If BW is lucky, they pass the test so the dredgings can be spread over adjacent farmers fields as damned good fertiliser. To do this, BW have to pay the farmers which is rich, considering that most of the dredgings either washed in from, or grew in those fields to start with.

 

George ex nb Alton retired

[springy]

That is a very interesting point.

 

At the HNBOC meeting last year I remember Malcolm Braine showing some slides of what he described as "phosphorus gas" flowing down into some of the locks on the BCN back in the 1970s. It was a white cloudy gas, which looked heavier than air as it was flowing around the top gates and down into the bottom of the lock. I don't know much about this (any chemists out there?) but I do remember something about 'phossy jaw' as being an influence in the Bryant and May Match Girl Strike of 1888 (some little of what I retain of O Level History 40 years ago!).

Cath

 

 

 

I have heard many times from a variety of sources stories of bits of the the BCN catching fire as a result

 

of the phosphorous waste "lost overboard" when it was a regular traffic (heading for disposal down a

 

disused mineshaft).

 

 

 

 

springy

 

 

[onionbargee]

just put a pole in and stir up any bit of the BCN, what comes up is truly evil oily chemical filth.

[Timleech]

It might be, so they have to test for it = money

Land fill tax = money

dredger = money

staff = money

admin = money

management = mo money

 

Maintance fund = NO money...

 

 

Mike

 

ps. I don't know the gauge the Leeds and Liverpool was built to, but I don't think it was ever that deep. Perhaps 4.5 or at best 5 ft.

 

Short Boats were built for a max draught of around 4', that would need a canal of at least 5' depth for them to get anywhere.

 

Bradshaw quotes available draughts of 3'9" over the top, 3'11" Leeds to Skipton, and 4'3" Blackburn to Liverpool. 6' or more original depth seems quite likely to me.

 

Tim

[JerryP]

When they dredged a section of the Grantham canal a few years ago ,all the spoil was put into a muck spreader and it all went onto nearby fields

[PhilR]

The Macclesfield Canal isn't renowned for the depth of channel. But, about 12 years ago the lower Macc was dredged to a channel depth of 1.6 metres (5 ft 3 ins) according to the contractor on the dredger! But soft banks, speeding motor boats and annual leaf fall soon diminish that ...............

[koukouvagia]

It might be, so they have to test for it = money

Land fill tax = money

dredger = money

staff = money

admin = money

management = mo money

 

Maintance fund = NO money...

 

 

 

But there'll be a lot of dredgers etc. available after BW has finished cleaning up the Bow Back Rivers for the Olympic Games. Let's hope they then get deployed around the rest of the system.

 

 

 

 

[Allan(nb Albert)]

We were watching a boat cleaning up the canal in Burnley on the TV this morning. Good Lads

They mentioned that the canal was probable 6-8 ft deep when it was built, but now needs dredging.

It occurred to me, ignoring the fact that they have to find some where to to dump the spoil, is there any evidence that the silt on the bottom of industrial canals might be toxic in some way.

Could this be another reason why they hesitate to dredge many of our canals?

 

Alex

 

These figures are just over a year old -

 

Dredging costs £80,000 to £200,000 per km for unpolluted spoil, and an eye watering £500,000 to £800,000 per km for polluted spoil.

 

Bw's current claim on dredging -

 

'BW plan to dredge, at a cost of £4.2 million, 45 km of canals and rivers in 2011-12, and in addition will spend £1.2 million on various high priority locations that have been identified as creating particular boating constraints.'

 

The following is the lengths (km) BW say they have dredged over the last 10 years (sorry I do not have a figure for 2010/11) -

 

2000-01 143

 

2001-02 113

 

2002-03 90

 

2003-04 95

 

2004-05 40

 

2005-06 64

 

2006-07 58

 

2007-08 53

 

2008-09 45

 

2009-10 64

[Chris Pink]

That makes me so angry, I'd do a kilometre with a teaspoon for £80,000.

 

These people are thieves and should have their dangly bits shut in a vice.

 

How these fuckwits ever managed to get hold of our canal system is one of life's great mysteries

 

Strewth.

 

And worth pointing out that at 50km a year it will take 64 years to do the system.

[Smudge]

When they dredged a section of the Grantham canal a few years ago ,all the spoil was put into a muck spreader and it all went onto nearby fields

Was that Dredging or desilting we are looking into getting the Slea done and apparently there is a big difference according to the ea.Dredgings have to be taken away as hazardest waste,but silt can be put to the bank or farmland

ps dont shoot the messenger this is what we were told

[Neil@CanalVoyagers]

All those dredgers in London are either 'Land & Water' or 'Wood, Hall and Heward' owned.

 

All this kind of work has been contracted out for years - the equipment is readily available and has been for many winters, its the funds to sub it out that are not forthcoming.

[Rod a mod from Tod]

On more than one occasion i have seen the canal banks being piled and at the same time dredged with the dredgings being used as backfill. Cant vouch if it was being tested for nastiness but i doubt it.

[Allan(nb Albert)]

That makes me so angry, I'd do a kilometre with a teaspoon for £80,000.

 

These people are thieves and should have their dangly bits shut in a vice.

 

How these fuckwits ever managed to get hold of our canal system is one of life's great mysteries

 

Strewth.

 

And worth pointing out that at 50km a year it will take 64 years to do the system.

 

Now I shall make you even more angry!

 

BW claim the length of canals and rivers that need dredging is decreasing year on year despite them doing less dredging!

[Smudge]

Now I shall make you even more angry!

 

BW claim the length of canals and rivers that need dredging is decreasing year on year despite them doing less dredging!

How many years and how many thousands did it take them to come up with that garbage

[Allan(nb Albert)]

How many years and how many thousands did it take them to come up with that garbage

 

I am somewhat reminded of a FOIA request I made regarding maintenance arrears. BW came up with figures that showed maintenance arrears were decreasing over time whilst saying that they were spending £30m less each year than the amount needed to keep the the waterways in the same condition as the previous year.

[WotEver]

On more than one occasion i have seen the canal banks being piled and at the same time dredged with the dredgings being used as backfill. Cant vouch if it was being tested for nastiness but i doubt it.

They did that a few years (3?) back at the bottom of The Ashby.

 

Tony

[jonathanA]

I missed a lot of the programme as I was snorting and ranting with indignation as I shouted at the TV!!

 

'joe and the team go out every thursday' the narrator informed us - as Jim Royle would say 'MY ARSE!'

 

its only in the last 12 months or so that many volunteers (organised by one of the hire boat operators - Lee Shepherd of Hapton Valley boats) have worked bloody hard to improve the burnley area of the L&L - I've only done two sundays but I know others who have done much more... (see pictures posted by me in canal news on this forum)

 

In fairness BW have made a work boat (Devon) available and I understand its maintained by a local mechanic on a voluntary basis. I've never seen the nice shiny work boat with grab shown on TV anywhere near rosegrove (I'll bow to others who may know better than me) They also provide the skips at rosegrove for emptying the rubbish into and last time I was on involved I was told that the 'bad lads' (community service) would unload the work boat into the skips.

 

judging by the many comments from other boaters and towpath users the sight of a BW work boat collecting rubbish out of the cut was as rare as the droppings of a childrens equine toy.... and not something that happens 'every thursday' as the TV suggested

 

can't blame BW for making the most of it though and the message was clear 'don't drop your crap in the cut' so hats off to all involved

 

Rant over - had to get that off my chest....

[sueb]

There is now a different method of 'dredging' being used. The mud is stirred then washed down the river. I hope this method isn't used on canals.

Sue

[billh]

There is now a different method of 'dredging' being used. The mud is stirred then washed down the river. I hope this method isn't used on canals.

Sue

That was a method used years ago . There were plug holes in the bed of the canal which provided the facility to drain off sections of canal for maintenance purposes. The plugs were pulled out and as the water drained (into the nearest stream or river) , gangs of men shovelled the mud into the remaining water as it flowed away. In this area, the mud was ultimately deposited in the River Mersey and later the Ship Canal, from where removal became someone else's problem.

With regard to toxic substances in canal silt, my opinion is that this is just an excuse to not do any dredging. It may well be a fact that there are measurable amounts of heavy metals etc etc in the silt but that is also true of much of the land in post industrial areas. Where I live, during my lifetime , huge areas of land have been used to dump all manner of waste- colliery tips, Corporation household waste, every type of industrial waste. Those places are now either developed with housing or nature has taken the land back and we have pleasant green areas. I don't see people dropping like flies as a result of all that alleged toxicity lurking in the canal or in the ground. Does anyone know of a case of a person becoming ill as a result of contact with toxic canal mud? I know about Weil's disease, but that's a different and more serious issue altogether.

Bill

[dor]

There is now a different method of 'dredging' being used. The mud is stirred then washed down the river. I hope this method isn't used on canals.

Sue

 

A few years ago, the Shroppie west of Nantwich was "dredged". This entailed the contractors digging out the sides and dumping it in the middle. I presume the thinking was that the passing boats would stir it up and it would, well, I don't know. It certainly wouldn't be vapourised, which is what I assume the muddle-headed management of BW thought. It was only a matter of a couple of months or so until it was all back at the sides again.

 

Two years later the contractors were back, this time to do it properly. The dredgings were initially used to fill big textile 'sausages'. the idea being the water would drain out and the remainder removed by road. The contractors told me this was because the dregings are now classified as hazardous waste. Anyway, the sausage-filling was a complete disaster so they finished up spreading it over the fields.