The Ouse Washes Website

an independent research and information project


Slackers (irrigation inlets)


Welcome to my website on at


Introduction

In the Washes and fens, the devices that control water flow for field irrigation are known as 'slackers' which are simply small sluice gates. Elsewhere they are often called penstocks.

A sluice is a water channel, often with a slight slope, where flow is controlled from one end, usually the higher or upstream end, by a plate known as a 'gate' that can be lifted to allow water to flow under it.

Gates generally slide vertically in grooves in a surrounding frame or set into the sides of the channel. They can be operated automatically but more often are manually controlled by a hand wheel turning a threaded rod which passes through a threaded boss fixed to the frame top or a girder above the gate, then down to the top of the gate. When the hand wheel is turned the rod revolves, moving up or down through the fixed boss nut, so raising or lowering the gate. Other methods include rack and pinion, and rope winches.

Slacker construction will depend on size and water pressure. The earliest slackers were completely wooden. I have only found one so far, and that is some way outside the washes. Then came slackers with an iron framework and a wooden gate, or all-metal ones. Small modern ones may have a plastic gate (in the form of HDPE, or high density polyethylene) and stainless steel framework. 
 


New Bedford/Hundred Foot River

The Hundred Foot River is the only source of water (other than direct precipitation, obviously) for maintaining water levels in the internal ditches. As the river is tidal, water can only be drawn during high tides, more or less every other day. The amount that can be taken depends on tides and fluvial flow. Salinity also has to be considered.

I have identified 22 locations along the Hundred Foot River where slackers allow water to be abstracted from it for irrigation - 17 into the Washes and 5 into the South Level.

The slackers on the Wash side are owned and operated by the Hundred Foot Washes IDB. Water is fed into a header dyke running along the side of the cradge bank (the inner, western or northern bank of the river), and from there via more controls into the field ditches. There is a natural fall across the washes towards the Delph, and each cross-ditch will need 4 or 5 water control points to prevent the water draining straight out into the Delph.

The slacker inlets and the header dyke (cradge ditch) silt up rapidly. The Hundred Foot Washes IDB is responsible for clearing silt from the cradge ditch and parts of some field ditches. Clearance of other ditches is the responsibilty of the land owners/tenants, such as the RSPB (which manages the washlands from Earith to Welney as one reserve according to their brochure).

back to contents

 

Black Sluice, NBR

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 
 

Youngs Holt

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 
 

Sutton Drove

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 
 

Reads

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 
 

Witcham Gravel

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 
 

Pontoon Wash

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 
 

Common Wash

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 
 

Ely Singers

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 
 

Oxlode

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 

Camnient slacker and flooded washes in 2012 by Eddy Edwards

Cambient

Location: NGR: TL
Visited:
Viewed: from opposite bank, 14th April 2012 .

back to contents

Camnient slacker and flooded washes in 2012 by Eddy Edwards

Dimmocks slacker and flooded washes in 2012 by Eddy Edwards

Dimmocks

Location: NGR: TL 501 884
Visited:
Viewed: from opposite bank, 20th March 2012 .
Note steel sheet piles and what apears to be a new slacker.
Strangely the washes at this point were flooded from side to side, even though this was during a drought, and following a very dry winter.
I have seen conflicting comments on this and will report more later.

back to contents

Dimmocks slacker and flooded washes in 2012 by Eddy Edwards

Hartleys slacker and flooded washes in 2012 by Eddy Edwards

Hartleys

Location: NGR: TL
Visited:
Viewed: from opposite bank, 14th April 2012 .

back to contents

Hartleys slacker and flooded washes in 2012 by Eddy Edwards



Kents slacker in 2011 by Eddy Edwards

Kents slacker in 2011 by Eddy Edwards
June 2011.
Handle secured by chain and padlock

Kents

Location: NGR: TL
Kents slacker in 2012 by Eddy Edwards
Viewed: from opposite bank, 14th April 2012 (above and right).

also Visited: 21st June 2011 (see left)

back to contents



Kents slacker in 2012 by Eddy Edwards
The yellow sign on the gate indicates this wash is owned or leased by the
Ely & District Wildfowlers Assoc.

Kents slacker and flooded washes in 2012 by Eddy Edwards

Kents slacker and flooded washes in 2012 by Eddy Edwards
Apr 2012, handle unsecured
 

Motts

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 
 

Deptfords

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 
 

Charity

Location: NGR: TL
Visited:
Viewed: from opposite bank,  2012 .

back to contents
 

Hagen Smart slacker in 2011 by Eddy Edwards

Hagen Smart

Location:
Visited:
Viewed: from opposite bank: 24th March 2011

Hagen Smart was a Washes Wildfowler who lived on the west bank of the Old Bedford River a couple of miles north of Welney, in a house his father James (once world speed skating champion,) built - Norway House.

back to contents

Hagen Smart slacker in 2011 by Eddy Edwards

Counterdrain and Old Bedford River


 



back to contents
 
 



back to contents
 
 



back to contents
 
Acknowledgements.
Text and photos except where noted © Eddy Edwards, 2010-12
If you think there are any errors or ommissions on this page or would like to comment, please
e-mail me
and your response will be added.

Related pages on this website
 
 
 
Related external websites
 
 
 
 
back to top of page   any comments?  please e-mail