Physical Geography of Epsom
For a narrative description of the physical geography of Epsom we feel that you can’t beat the following extract from the 1849 Report to the General Board of Health by William Lee, Esq., C.E., Superintending Inspector.
CONTOUR, GEOLOGY, AND METEOROLOGY OF THE DISTRICT
The legal boundaries of the parish are, almost without exception, those which any experienced engineer would recommend as the best for sanitary purposes, exclusive of all other considerations. With the exception of the north-east side, they run almost entirely along the water-shed, and enclose an amphitheatre about 3½ miles long and 2 miles wide. The town of Epsom is situated in the centre of this, with a good outfall to the Hog’s Mill river in the adjoining parish of Ewell. Three small tributaries of this stream have their source in Epsom, close to the town; but become united into one at the north-eastern boundary of the parish, about half a mile from Epsom Court. Very nearly the whole of the parish inclines to this point, and though any longitudinal section of the parish would show the town to be almost in the lowest part, there is yet a fall of nearly 40 feet from one side of the town to the other, measuring through the streets a length of about 1,300 yards. After a course of about six miles, the Hog’s Mill river discharges into the Thames at Kingston. The basin-like form of the parish causes the water to shoot rapidly from the sides of the hills, and I am informed that the town is subject to floods during thunder-storms; but the water soon passes off, and this does not contravene the fact that the contour of Epsom is very favourable to the discharge of surface-water. It would be easy, at a trifling cost, to improve the outfall so as to obviate the inconvenience of these occasional floods. The surface-soil of Epsom is much diversified. On the south-east side, forming the Downs, it is little more than disintegrated chalk, constituting a very thin coating of a porous character. It produces a fine turf, upon part of which the celebrated racecourse is situated. It has been considered too light and thin to be very productive, but is capable of great improvement if ploughed and top-dressed with clay. The soil on the north-west is heavy clay, which in seasons of drought becomes baked, and is said to crack often a yard in depth. The opposite mode of treatment to that recommended for the downs would render this land also very fertile, namely, thorough drainage, deep ploughing, fallows, and the application of light porous material, as top-dressing. Between these are all the gradations from clay to gravel, sand, the common vegetable humus, and light soil with flints. On the north-east, in Hog’s Mill Valley, it is an alluvium derived from all these sources, and, if properly drained, is capable, with the addition of the liquid sewage manure of Epsom, of attaining the highest possible fertility. The subsoil on the north-east is a bed of yellow clay, not more than a foot thick; on the north-west a very retentive loamy clay. There is a vein of sand running from the north-west to the south-east, but the general character of the subsoil on the southwest of the parish is gravel of the ordinary kind found in the London basin, and varying from 3 to 9 feet thick. On a great portion of the south-east side there is no subsoil whatever. The vegetable humus lies immediately upon the chalk. The geological strata are gravel, London clay, plastic clay, greensand, and chalk. The town of Epsom is situate at the junction of these beds. The chalk rises rapidly south-east by east, and there are several pits close to the town. The London clay ranges from the south-west to the north-west of the parish, and in it are found the mineral springs for which Epsom was once so celebrated. The clay is covered by gravel, in which there are some large and excellent ponds of water upon the common, near the lodge of Woodcote Park. On the north-east at the outlet of the valley the stratum is the greensand. In the bottom of the valley, extending westward from the church to the Dorking-road, there is a stratum of the greensand mixed with fragments of chalk. This immediately overlies the chalk, and is the locality of a singular phenomenon called “the Earth Bourne”, which will require to be provided for in any arrangements for draining the town. The Earth Bourne is an intermittent spring, permeating the whole of this bed of sand and gravel, usually rising within a foot or two of the surface over a considerable area, and sometimes oozing out above the ground. Mr. Everest, to whom I am indebted for much information on this, and many other matters connected with the inquiry, says:- “Its duration and the time of its recurrence are alike irregular, although it seldom fails to succeed a wet summer. Sometimes it does not appear for three or four years, and then flows for two or three years successively. Its duration varies from four to eight months. It generally commences running soon after Christmas, and disappears about May or June. The wells gradually rise, and frequently overflow, and the water is beautifully clear and sweet.” The Earth Bourne is produced by the simple laws of hydraulic pressure. The area over which it extends is in the bottom of the basin, and the chalk rising from beneath the gravel at that point assumes the form of bold sloping hills, and attains a considerable altitude on the downs. The absorbent power of the chalk is so great that comparatively little of the rainfall is evaporated; and during ordinary rain the water is constantly descending through the chalk to the level of the wells and springs and other outlets in the valley. After long-continued and excessive rain, however, these outlets become insufficient for its discharge, and it accumulates in the chalk until the vertical pressure forces it up through the gravel in the form of a syphon, and produces the “Earth Bourne”. No person in Epsom has kept any meteorological tables. The rainfall is stated to be under the average. I should not assume a greater quantity than 25 inches annually for any calculations respecting sanitary works. The prevalent wind is from the S.W. The climate of Epsom is genial. The winds from the Downs and Common are soft and refreshing. Naturally, every circumstance connected with the position of the town is in the highest degree favourable to the health and longevity of the inhabitants. All the medical witnesses concurred in saying that but for its defective sanitary condition it would be exceedingly healthy; while two or three of the inhabitants continually reiterated their objections to the Public Health Act, by informing me that Epsom was one of the most healthy places in England. This statement is calculated to afford very little consolation to the friends of those who have died within the last two or three years from preventible diseases, and I am sorry to say that the assertion is incorrect, as will fully appear hereafter; but, at the same time, I have no hesitation in saying, that, with such great natural advantages, the powers conferred by the Public Health Act are capable of raising the sanitary condition of Epsom to the highest standard attainable in this country.
Jump List
Topography (or how the ground is shaped)
Geology (or the physical structure and substance of the earth)
- https://www.epsom-ewell.gov.uk/sites/default/files/documents/residents/planning/planning-policy/SFRA%20APPENDIXH.pdf
- http://mapapps.bgs.ac.uk/geologyofbritain/home.html?location=epsom
- https://www.bgs.ac.uk/data/mapViewers/home.html
Biodiversity
Weather/Climate