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From early times sites for human settlements have been determined by the presence of a suitable water supply and this in turn is directly related to the geology, topography and climate of the neighbourhood. It is one of the objects of this handbook to show what an important part the water supply has played in the growth and development of Huddersfield.
The district of which Huddersfield is the natural centre lies among the foothills of the Pennines at the junction of the River Colne and its tributaries, the Holme and the Fenay Beck. The geology of the area has been described by many writers, and among the works most useful to consult for fuller details are the Geology of Yorkshire, by Kendall and Wroot (13) ; and three memoirs published by the Geological Survey, viz. : The Country Around Huddersfield and Halifax, 1930 (27) ; Holmfirth and Glossop, 1933 (4) ; and The Pennines and Adjacent Areas, 1936 (28) ; the latter by Dr. D. A. Wray. In this memoir by Dr. Wray he points out that geologically the Pennine uplands fall readily into three well marked divisions :—
In each of these three belts or zones are distinctive types of moorland directly dependent on the types of rock of which they are composed.
The Central Pennines, in which our district lies, is formed entirely of sedimentary rocks of Carboniferous Age. The beds of rock of which it is composed were originally in horizontal, superimposed layers, but have since been displaced by an enormous uplift formerly described as an anticline but now shown to be a broad monocline about seventy miles long, which runs west-northwest and south-south-east, the beds having a gradual dip to the east and a steep dip on the west, the western margin being defined by a series of great fractures or faults. Hence the highest part of the uplands is the western scarp overlooking the Lancashire plain. The maximum elevation of the Central Pennines is at the Peak in Derbyshire ; from there it sags towards Holmfirth, then rises again towards Skipton.
This uplift was followed by prolonged weathering and denudation resulting in the newer beds being completely removed from the summit plateau, leaving the denuded edges exposed at lower levels and whose individual beds correspond on the east and west sides of the axis. The effect of the difference of dip on the two sides of the axis is strikingly shown by comparing the relative widths of outcrop of corresponding beds. As Dr, Wray points out, "the base of the Coal Measures is about one mile to the west of Blackstone Edge, while on the eastern side of the axis the total width of outcrop of the corresponding measures up to the base of the Coal Measures is at least eight miles." The area of special interest to us is confined to that part of the easterly dip slope extending in a semicircle from Buckstones in the north-west to Stanedge, thence to Black Hill, Hepworth, Fulstone, Shelley, Lepton, Whitley and Kirkheaton in the south-east. The streams draining this area form the tributaries of the Colne and this in turn joins the Calder at Cooper Bridge to the north-east of Huddersfield.
All the beds of rock in this area belong to the Upper Carboniferous formations — the Millstone Grits and the Lower Coal Measures. In addition to these solid formations are superficial deposits. Their sequence is shown in the borehole at Bankfield Mills, Moldgreen, page 87.
As pointed out by Dr. Wray, nothing whatever is known directly of the nature of any rocks older than the Upper Sabden Shales, and these are recorded at Crimsworth Dean in the north, in Edale in the south, and near Greenfield in the west, all beyond our catchment area. Our deepest borings (Messrs. W.T. Johnson and Sons, of Moldgreen, Messrs. Blamires, Limited, and the Rastrick borehole of the Brighouse Corporation) do not go below the Lower Kinderscout Grits.
The Pennine plateau in this district, is formed of the Millstone Grits, and several of our moorland streams, feeders of local reservoirs, cut down to the Kinderscout Grits, e.g., those in Wessenden, Ramsden Clough, and Marsden Clough ; the latter stream, a feeder of the Bilberry reservoir, is crossed by a natural bridge of Kinderscout Grit (Fig. 2). Good sections are exposed on the sides of the deep cloughs showing alternating beds of resistent sandstones and softer shales and mudstones ; on the main beds of sandstone occur fireclay with thin seams of coal. These picturesque cloughs with their rugged, rocky edges and steep slopes are strewn with tumbled blocks of grit.
Owing to the dip of the beds on the eastern slope, the grits tend to creep over the more readily denuded shales beneath and extensive landslips have occurred, as at March Hill (Fig. 3), West Nab, Deanhead Valley, near Scammonden, the eastern slope of Wholestone Moor, and in the lower Holme valley, east of Beaumont Park.
The most conspicuous and uniform of the Millstone Grits is the Rough Rock, the uppermost of the series. It dominates the landscape to the west and south-west of Huddersfield, forming the sandy plateaux of Crosland Moor, Netherton Moor and Honley Moor (Fig. 1). The Rough Rock is extensively quarried at Crosland Moor and provides Huddersfield with much good building stone.
Each bed of sandstone forms a long dip slope falling gently to the east, but westwards forms an abrupt escarpment or "edge," as at Longwood Edge, Crosland Edge, Edge Moor, and Royd Edge. Although the beds have a fairly uniform dip, those from Brow Grains to Honley, a distance of about five miles, show a broad, shallow syncline, the axis of which follows the valley of the Meltham Brook. This flexure is well seen on the sky-line from West Nab to Shooters Nab (Fig. 1). The Rough Rock plateau reaches its greatest altitude at West Nab, 1,641 ft. O.D., where huge blocks of grit are spread over the summit, whose curious shapes testify to prolonged weathering.
The grits cross the River Holme then disappear under the Lower Coal Measures, the latter forming the bold escarpment on which Castle Hill with its tower is a prominent land-mark.
Like the Millstone Grits, the Coal Measures, as shown in the boring, page 87, consist of alternating beds of sandstone, shale and mudstone, with beds of fireclay and coal. The coal seams become relatively thicker and more important as we pass from the Lower to the Middle Coal Measures, and to the east of the town the area is studded with colliery villages, e.g., Lepton, Whitley, Hopton, Thornhill, Flockton and Emley. Borings in the Coal Measure area show that the Rough Rock is continuous beneath, and for ten miles or more it has a uniform dip of approximately one in twenty-five or an angle from two-and-a-half to three degrees.
The Coal Measures, though similar in structure to the Millstone Grits, form scenic features in marked contrast to those of the Rough Rock. The great preponderance of shales over sandstones in the Coal Measure area results in a more even surface of the undulating hills, but where the sandstones crop out they give a step-like character to the hillsides (Fig. 4). In the foreground is the Rough Rock, passing beneath the Lower Coal Measure escarpment, with Castle Hill, Almondbury, on the right, with step-like terraces on the slope.
The beds forming the solid geology of the district are masked over a large area at the lower levels and valleys by superficial deposits of boulder clay, sand and gravel. These deposits are revealed during excavations for drains, water mains, and foundations for buildings in the town up to an altitude of 400 ft. O.D. and patches occur at higher levels on the clough sides. Many sections were exposed during the Great War and some were then described and illustrated (24). These facts together with details brought out in the recent Survey Memoirs (27, 5), provide an explanation of these deposits and show that they belong to the last Ice Age and phenomena succeeding that period. Put briefly, deposits on the west of the Pennines show that an enormous sea of ice crossed the Irish Sea, invaded the Lancashire plain and pushed its way up the Pennine slopes to near the head waters of the River Colne, but in our district does not seem to have crossed the ridge and invaded our valleys on the east. It is probable, however, that there would be small lobes of ice on the eastern fringe of the plateau and that corrie glaciers would form in the deep hollows at the head of the Colne and Holme, the melt-waters from which and the downhill flow of ice, snow and mud, would account for many of these deposits which contain only local material. The extensive flooding of our narrow valleys would tend to remove traces of local glaciation.
On the eastern side, in Lower Calderdale, at the period of maximum glaciation, the great ice sheet filling the Vale of York reached as far as the Dearne Valley in a westerly direction and, closing the outlet of the Calder up to 405 ft. O.D., produced a Lake Calderdale which extended far up the Valleys of the Colne and Holme and completely submerged the centre of Huddersfield (see Museum Handbook No. 8 and 26. Fig. 11).
It is probable we have here an explanation of the origin of the extensive local deposits of clay and boulders. A good section is seen at the Hillhouse Brick and Tile Works, and much was exposed during the recent excavations of the Cloth Hall site.
Our present river flats are covered by a more recent thick bed of alluvium composed of sandy clay, loam and gravel.
The eastern slope of the Pennines with which we are specially concerned, may be conveniently divided into three zones of altitude :— (1) The summit plateau ; (2) Foothills and spurs ; and (3) Lowlands (Fig. 5).
Roughly coinciding with the three zones of altitude are striking differences in rainfall. The prevailing winds are from the south-west and coming from the Atlantic saturated with moisture, ascend the Pennine slopes and deposit their moisture on approaching the higher ground at the Stanedge, Holme Moss and Black Hill. Here is the wettest part of our district having a mean annual rainfall from fifty to nearly sixty inches. The general summit plateau has a rainfall from fifty to fifty-five inches and from this wet region the rainfall lowers to the north-east, showing a distinct rain shadow (Fig. 7), notwithstanding the fact that the leeward side of the Pennines receives abundant moisture, e.g., the rainfall on the spurs and foothills is forty-five to thirty-five inches ; at Dewsbury the rainfall is only twenty-five inches, a difference of thirty inches in fifteen miles.
The following records of rainfall were taken at the Edgerton Cemetery, altitude 411 ft., from 1876 up to and including December, 1921, when the instruments were transferred to Ravensknowle Park. From January, 1922, the records were taken at the Ravensknowle Meteorological Station, altitude 325 ft., and supplied by Miss Ellen Gallwey, the recorder.
These records show the normal average rainfall for the standard period of 1881–1915 inclusive to be as follows :—
|Normal Yearly Total||33.91|
From 1916–1935 inclusive the normal rainfall averages are :
|Normal Yearly Total||32.45|
a decrease of 1.46 inches from the last average of which the month of June accounts for .70 inch.
Thus since 1881 there has been a gradual decrease in rainfall in this area, and this corresponds with a decrease for the period for the country as a whole. Where estimates of supply have been based on a drought period of forty days, this should now be taken as a minimum and provision made for an increased drought.
There is a corresponding difference in temperature, the year's mean at the higher summits being 42 deg. F., while that at the lower levels is 47.5 deg. F. Thus we have a high, wet, cold zone to the west and a low-lying, drier and warmer zone to the east ; between the two are the spurs and foothills which have an intermediate temperature and rainfall ; factors which play an important part in the distribution and activities of the life of the district. This high, wet region (the site of our reservoirs) is an important catchment area providing, both in quality and quantity, a supply of water suitable for the needs of a large section of the industrial population of south-west Yorkshire. The need for preserving this as a catchment area and to prevent pollution, has resulted in a reduced population and many upland farms are now derelict.
Our main water supplies are dependent on run-off, and this is favoured by the physical and climatic conditions above described. The high rainfall on the summit ridge ensures a saturated subsoil and this in turn allows a greater proportion of each fall to find its way to streams feeding the reservoirs. Run-off is also favoured by the steep slopes of the clough sides which run back into the high plateau. This plateau has a low temperature which greatly reduces loss by evaporation. Further, water percolating through the surface beds of grit, on reaching the underlying impermeable shales, follows the dip of the beds and issues as springs on the clough sides.
Huddersfield, therefore, is fortunate in having a large and favourable catchment area within easy reach.
Recently (1913) by taking over the reservoir at Deanhead, we have invaded the drainage area of the Calder, with which the Colne unites at Cooper Bridge on the eastern edge of the Borough boundary.