1. Waye Water.
Stephen Crittenden
14/03/2008
1
A Preliminary Investigation of the Underground Water
Supply at Waye.
by
Stephen Crittenden BSc, MSc, PhD.
Independent Geological Consultant.
October, 2003.
Introduction.
This document is a general introduction to the disposition of the groundwater source
of the Domestic Water Supply at the hamlet of Waye. It is stressed that the comments
and discussion in this document are made purely from surface observations by and
from the best judgement of Dr Stephen Crittenden, Independent Geological
Consultant. For this study no scientific measurements or tests have been performed to
assess the underground water situation at Waye. Such tests, measurements and
procedures may be carried out in the future. Accordingly the correctness or accuracy
of the information and interpretation herein cannot be warranted and under no
circumstances should any such information or interpretation be relied upon as the sole
basis for any drilling or financial decision. In no event will Dr Stephen Crittenden be
liable for any damages including but not limited to, indirect, special or consequential
damages, resulting from the use of any information or interpretation provided.
The three houses at Waye; Waye Cottage, Waye Farm and Lower Waye Farm, are
each supplied with domestic water by their own dug well /cistern. Each is in the order
of 10metres deep (30 – 35 feet) and at some time in the past hand dug. The three wells
are approximately within 50 metres of each other. The two wells supplying the
medieval long houses of Waye Farm and Waye Cottage were dug probably in the 14 /
15th
Centuries in fractured / jointed rotten granite to a depth of about 30 feet
(10metres). They are unlined and are about 1 yard square in cross section. The well at
Lower Waye Farm is topographically lower than the other two but is also dug
predominantly in granite. It is lined with dressed granite setts / bricks and was
probably dug some time in the 19th
century. Further investigation of this well may
reveal that it is dug partially in growan /alluvium above granite.
It is the occurrence of a ready supply by springs of fresh, potable water at Waye that
caused it to be the site of dwellings of a settled farming community well before
Medieval times. The occurrence of freshwater springs at the head of this valley of the
tributary to the River Teign would have made the site attractive for human habitation.
As the springs are intermittent in nature at some time in the past wells /cisterns were
dug in order to store and to maintain a steady supply of water.
Groundwater.
It is a matter of common sense that there is a relationship between rainfall on
Dartmoor, the level of water in the Fernworthy Reservoir and flow in the headwater
streams of the River Teign in the Chagford area. It is also common sense that there is
a relationship between rainfall and the level of water in the three dug wells
(domestic water supply) at the hamlet of Waye. Observation shows that in the Spring
after a wet winter the water level in the wells rises to a level substantially higher than
that seen in the Summer months.

2. Waye Water.
Stephen Crittenden
14/03/2008
2
Rainfall water is distributed as run-off, percolation and evaporation. Run-off does not
contribute to wells and springs. However, percolation does contribute to wells and
springs by downward infiltration of water to bedrocks to replenish groundwater. This
groundwater supplied by the infiltration of rain and snow melt is described as
meteoric.
Below a certain level beneath the ground surface at Waye all porous, permeable and
fissured rocks are saturated with water (ie. groundwater). The upper surface of the
groundwater is termed the water table. The water table surface follows in general the
topography of the ground above; it is arched up beneath hills and curves down
beneath hollows and vales.
Beneath the ground surface three successive zones are recognized. These zones are
dynamic and at Waye are very important for understanding the behaviour cycle of the
water level in the three dug wells and the local spring activity patterns during the year.
a) The uppermost zone is the Zone of Non-saturation and is never completely
water filled. It is the zone through which water percolates to the deeper zones.
b) The Zone of Intermittent Saturation extends from the highest level ever
reached by groundwater (after prolonged wet weather), the water table, down
to the lowest level to which the water table drops after drought. If the top
surface of this zone reaches the ground surface then intermittent springs are
formed. This can be observed at Waye, Waye Farm in particular, where a
spring is used for agricultural water supply, and in the road between Waye and
Tor Hill Farm (near the badger setts). The three wells at Waye are mostly in
this zone and during the winter months over the last 10 years the water level at
the Waye Cottage well is very close to the surface (a few feet) and drops
substantially in the Summer.
c) The Zone of Permanent Saturation extends down to the limit beneath which
groundwater is never found. When the top surface of this zone rises above
ground level then permanent streams, swamps, lakes and rivers are formed. At
present only the bottom most few feet of the wells at Waye penetrate this zone.
Simple Geology and Bedrock
The storage and circulation of ground water at Waye is very dependent on the local
geology. If water passes through a rock it is permeable. Permeable rocks can be
porous: such as sandstones, or non-porous such as granite. At Waye the bedrock is
Dartmoor Granite and is overlain by a thin veneer of soil, with in some places
alluvium that has been worked for tin some time in the past and ‘growan’ – rotten
decomposing granite. Granite is pervious due to the presence of interconnected open
joints and fissures (both macro and micro sized) through which water can flow. The
rate of water movement through a permeable rock depends on the total permeability
(capacity of the rock to allow water to pass through it), the hydraulic gradient and the
rainfall catchment area and can be a very low rate indeed, as at Waye. Indeed the rate
of the water storage top up of the “granite aquifer” by percolation may be very, very
slow.
At Waye the water migrates through the rock by the most permeable routes and
emerges by natural openings (to form springs and seeps), by the three artificial
openings (hand dug wells) and by direct feed into the small streams. The actual water
storage capacity of the granite beneath Waye is probably not high and is controlled by
the density and volume of the open fractures and joints for a given volume of rock.

3. Waye Water.
Stephen Crittenden
14/03/2008
3
Springs at Waye
The lie of the land and direct observation indicates that there are a number of spring
sites in the vicinity of the hamlet of Waye. Under present climate / weather conditions
these springs are mostly intermittent in nature. These springs provide some
contribution of water to the headwater tributaries of the River Teign. The intermittent
springs occur where the Zone of Intermittent Saturation meets the ground surface. The
top surface of this zone is a water table that oscillates up and down depending upon
the supply of percolating water from rainfall. This water enters joints, fissures and
fractures in the massive granite and then issues where the water table meets the
surface. During and after periods of prolonged drought the water table falls and the
spring accordingly “dries up”.
Wells at Waye
The wells at Waye were probably sited originally where there were surface springs
that depending upon the climate and the weather would have been either intermittent
or permanent. The wells at Waye were dug to penetrate the lower part of the Zone of
Intermittent Saturation and the upper part of the Zone of Permanent Saturation thus
giving a year round supply of domestic water. Shallow wells may dry up when the top
of the Zone of Permanent Saturation is not penetrated. These wells at Waye would /
may have flowed at sufficient water rates during parts of the year to be exploited as a
continuous supply of water used to flush the down slope, shippon part of the long
houses. These spring sites would have been associated with fractured and jointed
rotten granite and the hand digging of the wells would have exploited these
weaknesses in the granite. The ground water percolates into the well and then rises to
a level that depends on the head or hydraulic pressure behind it.
Rate of Abstraction
The rate of abstraction of water for domestic use from the wells at Waye are / should
be regulated by a number of factors.
A. The water level in a well will fall if the “granite aquifer” is not able to transmit
the percolating water to the well at the rate with which water is being
withdrawn.
B. A localized cone of depression – draw down of the water table, may occur if
excessive rates of abstraction are used in a well even if it is penetrating the
Zone of Permanent Saturation.
C. The rate of abstraction of water through all the wells tapping the storage may
be exceeding the rate at which the storage is being recharged by infiltration.
This is very serious as it results in the lowering of the water table and
emptying of the aquifer that may have taken decades to fill. It may then take
some years for the aquifer to recharge and the water table to rise to its former
level in the area.
D. It is never sensible to pump a well dry. Such a practice runs the risk of
permanently damaging the water transmission ability of the fractures and
fissures that ‘feed’ the well and indeed can adversely affect the water table
level for some considerable radial distance from the well. Water travels by
preferred routes in the fractured granite aquifer and routes can in some

4. Waye Water.
Stephen Crittenden
14/03/2008
4
instances become plugged /blocked such that a well may become semi-
bypassed.
In the past water abstraction rates were regulated by the domestic needs of the three
households and the climate / weather was such that recharge kept up with abstraction.
However, modern day living – daily baths/showers, washing machine, dish washers,
flushing toilets - and climate change have combined to make the domestic water
supply to the hamlet of Waye a problem. The water level in the three wells is as low
as it has ever been, in the last 20 years at least, and there is no oral history (or indeed
no written history that I have seen) of any of the wells at Waye ever running dry.
Water for agricultural use was supplied by springs outside the domestic curtilage of
the farm buildings and regulated by abstraction licenses.
This summer of 2003 has been exceedingly dry and the pattern of climate change
would indicate that dry summers will be the norm for the future. Over the last decade
or so summers have become progressively drier and the amount of annual
precipitation has been decreasing. Accordingly care must be excercised now and in
the future, in the amount of the water abstracted from the wells for domestic use at
Waye. The aquifer must be allowed to recharge, if possible, back to its former levels.
This can be gauged empirically by seeing how far the water level in the wells rises
this winter, assuming we receive a good amount of rain and / or snow. The danger
will be then that the domestic users of the water will relax and be less vigilant in their
care of how much water is being used each day.
It is apparent that the sustainable domestic use of the water from the three wells is far
below the maximum domestic abstraction limits of 20 cubic metres / day per well set
by the Department of the Environment (equivalent to 4,400 gallons / day per well). A
typical well in Granite in Devon usually flows less than 3 – 4 cubic meters /day.
Accordingly each of the dwellings at Waye must take care in their domestic water use
so as not to violate /derogate any of the protected domestic water rights of their
neighbours.
Remedies
The immediate remedy is to restrict water consumption from the three wells to
domestic purposes only. This domestic use at each household can be reduced by a
number of simple measures.
• Turn off taps while using a basin thus not allowing the water to run to waste.
• Minimise the use of a dishwasher – if used then only use with a full load.
• Minimise the use of a clothes washer – if used then only use with a full load.
Preferably use the launderette in times of drought!
• Take showers not a bath.
• Collect rainwater in a butt or butts and use for garden if need to do so.
• Place a brick in the lavatory cistern to reduce the amount of water used per
flush.
• Refill the lavatory cistern with a bucket of water from the rain butt.
• Wash the car at the ‘car-wash’ in Okehampton.

5. Waye Water.
Stephen Crittenden
14/03/2008
5
Other remedies are not simple but aim to increase and secure for the future the
domestic water supply for Waye in some way. Three alternatives are summarized (but
not costed or risked) as follows:
• Dig each well deeper into the Zone of Permanent Saturation. I am not clear
how this could be accomplished but it would be a ‘messy’ job and would rely
on the newly dug section of well intersecting water filled open fissures,
fractures and joints. The water would have to be drinkable. How high the
water level would then rise in the well would depend upon the hydraulic
gradient in the granite reservoir. This deepening of the wells at Waye would
make downhole pumps necessary to ‘lift’ the water from the wells to the
surface. Downhole pumps are expensive and take up space so the wells would
have to be deepened considerably. At present water in the three wells at Waye
is lifted to the surface by pumps at ground level. Pumps draw water by
suction. The pressure at the inlet (the foot valve) is reduced below that exerted
by the atmosphere on the surface of the water so that water is forced through
the inlet valve and up the suction pipe. If pump suction pressure were at
absolute zero the greatest height to which atmospheric pressure would force
water would be about 34 feet. This is the limiting height at which a pump is set
above the lowest water surface (ie Summer level) in the well and for practical
purposes is about 20 – 25 feet. The present (Sept / Oct, 2003) water level in
the well at Waye Cottage is about 26 feet below the pump.
• Drill a borehole or boreholes at Waye into the granite deep into the Zone of
Permanent Saturation. The hope would be that a number of fresh and drinkable
water bearing fissures, fractures and joints would be intersected by the well
bore thus providing multiple sources of water influx into the well bore. The
location and the number of boreholes to be drilled are open to investigation
and debate and a thorough site survey would need to be done to assess existing
water rights, contamination possibilities etc etc. Various permissions (if
necessary) would have to be sought for the siting and drilling of a borehole
and for the eventual abstraction of water. If a deep (about 65metres) borehole
were drilled then the chances of obtaining water are good but….how much
water and of what quality cannot be determined. It is no good drilling
boreholes if the water is not drinkable (or would be expensive to treat).
Boreholes supply good drinkable water at nearby farms; I believe at Thorn
(Michael Stanbury) and at Waye Cross (Mark Loram). The depth, type and
flow rates of these two boreholes and any others nearby need to be established
before meaningful comparisons can be made with Waye. The borehole drilled
at Tor View Farm (Richard Knox) at Whiddon Down supplies a large quantity
of iron rich water that is not fit for human consumption; it goes to the pigs I
understand. This high level of iron I believe may be due to the fact that the
aquifer penetrated is metamorphic Culm Measures and not granite. This will
have to be confirmed. The hamlet of Waye is underlain by growan and
alluvium, rotten granite and hard ‘blue’ granite; not by Culm Measures or the
metamorphic aureole. Interestingly at Waye there is the possibility that a
borehole could be sited such that it taps two sources of water; one from an
overlying alluvial aquifer where the water is possibly more mobile and thus
prone to contamination and one from the granite aquifer beneath. The
thickness and extent of the alluvial deposits to the north and north east of the
hamlet need to be determined.

6. Waye Water.
Stephen Crittenden
14/03/2008
6
• Connection to the South West Water supply system is a possibility as the
nearest main is I believe approximately 700metres west of Waye Cottage. A
connection would guarantee a good supply of high quality domestic water; but
at what price?
Stephen Crittenden
October 30th
, 2003.