3.2    Environmental information

3.2.1    Physical

3.2.1.1    Climate

The site has a reasonably mild climate because of the following factors: located in the south of England, near the sea, the site is flat and is not exposed being sheltered by trees on its eastern, western and northern boundaries and by the railway embankment in the north.  
Areas of shade on the site:
i)    along the banks of the River Ems (especially the western and northern banks) mainly due to large Crack Willow trees and the railway embankment to the north
ii)    Palmer’s Road copse (south-western corner)
iii)    Lumley copse (eastern boundary)
iv)    Line of willows across the North Meadow
v)    Small fenced copse of mainly Alders opposite the gasholder
vi)    South Meadow, mainly shaded by trees along banks of the River Ems ands a tall Bramble hedge along west boundary of Gooseberry Cottage.
vii)    Various industrial buildings on the western boundary, including a gasholder.
The wooded areas as well as the buildings on the industrial estate (western boundary) provide protection to the main meadow from the prevailing winds.
Areas with the most sun:
i)    Central Meadow, particularly along the eastern edge which is west facing, protected by trees in east and north but no direct shade. The whole meadow is also given some protection by the causeway/raised path.
ii)    North Meadow, this area is not quite so sunny as the area described under i), due to the line of willows to the south.
iii)    Seagull Lane patch, protected by willows to the east, open aspect to the west.
No weather record information is available for the site.

3.2.1.2    Hydrology

a)    Flowing water: rivers and streams
The River Ems is a chalk river with its source about 6 miles to the north. Most of the river is in West Sussex but it is the southern section of the river which flows through the site along the northern and western boundaries. It enters Brook Meadow from the north via a culvert under the railway line at the north-eastern corner of the site and is also fed by a spring issuing in meadows to the north of the railway line. It runs along the northern and western edges of the site and then runs through Palmer’s Road copse before leaving Brook Meadow via a culvert in the south under the A259 and down into the harbour at Dolphin Lake.
According to reports by local residents, the River Ems used to be tidal as far upstream as the gasholder until 1974, with reports of fish such as Flounder being caught in the river. Apparently, a deeper sill was put in during the construction of the A259 which prevented fish from swimming upstream. Recent evidence suggests that the lower section of the river may still be tidal. Several species of snails which are known to occur in saltwater were found in the two southern-most sections of the River Ems (See ‘Survey of the River Ems at Brook Meadow’ by Chloe Delgery, Portsmouth University, June 2005).
The present course of the River Ems is not the original one since it was diverted in the late nineteenth century, before which it used to run along the eastern edge of the so-called water meadows which have now become Brook Meadow. Before the northern embankment was built, the Ems regularly flooded into Brook Meadow. A short section of the northern banks of the River Ems is lined with wooden boards to reinforce the riverbank at the point where the river was diverted south. The only part of the river which still floods is the southern most section in Palmers Road copse. This area regularly floods especially in the winter (2001 to 2005). This is the lower section of the original linear millpond which was drained in the late 1970’s for the construction of the short bypass (A259).
The Ems is a medium to fast flowing river. The riverbanks are lined with mainly mature Crack Willows, especially the western and northern banks and part of the eastern banks (in the south).
A diminutive watercourse used to branch south from the Ems not far from Lumley Mill marking the Parish and County boundary. This ditch more or less dried up when the River Ems was diverted in 1875. See section 3.2.3.1 for a brief history of this section of the River Ems.
Pollution
The chalk river is relatively unpolluted and is reported to be the cleanest in West Sussex. However, surface water from the west drains into the river via surface water drains (map 1 Appendix 8) and several of the industrial units on Palmers Road and Seagull Lane have their surface water draining directly into the River via pipes with non return flaps.
The results of a survey carried out by Portsmouth University (2005) indicate that the water quality is good.
The Lumley Stream flows along the eastern boundary of the site. It is fed by the Ems from Lumley Mill and runs alongside Lumley Road, through Lumley Road copse until it enters Peter Pond, which flows into Slipper Mill Pond, and thereafter into the harbour. The Lumley Stream is tidal up to the Lumley Cottages, the water flowing upstream is therefore slightly saline. The stream regularly floods its banks especially after heavy rainfall and a high tide. In November 2005, a large area of the Central Meadow (eastern side) was inundated see map 5
The Lumley Stream is narrower than the Ems and unless there is a high tide it is much faster flowing. The banks of the stream are lined with many mature trees, mainly Oak, Sycamore, Ash with some Elm. The Elms have been infected with Dutch Elm disease. There is a large area of dead Elms on the land at the junction of Lumley Path with Lumley Road (marked with DE on map 2 in Appendix 6). Many of these Elms have been felled without HBC authorisation by a local resident who has been removing it for firewood (autumn and winter 2005). This felling work has caused considerable damage to this valuable wildlife habitat.
Water levels
The water level in both these rivers varies enormously from summer to winter. In the past, the flow of water in the main branch of the River Ems used to dry up regularly in the summer. This still can happen as it did in September 2003.
The Lumley Stream also gets very full in the winter and floods regularly (especially in January 2001 and November 2005) but it nearly dries up in the summer.
There is a sluice to the north at Lumley Mill which serves to control the flow of water in both the main part of the River Ems and in the Lumley Stream. The sluice is in need of urgent repair and at present (2005) it is leaking too much water into the Lumley Stream. The effects of this were felt in the summer of 2005 when there was hardly any water flowing into the lower reaches of the River Ems. This was not as serious for wildlife as it could have been because of the ponding effect created when this section of the river was a linear millpond providing the motive power for the watermill.
The linear millpond used to be at least 1 metre deep and about 20 metres wide at the widest point. The river has silted up considerably since then because it is no longer dredged as it would have been when the watermill was operating and is now only about 50 cm deep in the pools and about 5 metres wide. At high tide and heavy rainfall, the River Ems floods its banks extending to about 15 metres wide. See Appendix 1, map 5 for areas liable to flooding.

b)    Standing water:
i)    ponds, ditches and standing water
There are no ditches of any substance on the site apart from a small ditch running alongside the western boundary of the Seagull Lane patch. There are traces of the original ditch which marked the Parish and County boundary referred to above under rivers and streams. Nor are there any ponds to speak of apart from a temporary area of standing water near the Lumley gate (called the ‘Lumley puddle’) which only forms at times of high rainfall and high tides. There is sometimes standing water in front of the sluice at the junction of the Ems with the outlet to the South Meadow or balancing pond.
The balancing pond (South Meadow) gets flooded on purpose by the Environment Agency removing the ‘sluice gates’ when water levels in the River Ems are high after heavy rainfall. This occurred in January 2001 when the South Meadow was totally flooded for several weeks. The southeast corner of the South Meadow near the South entrance was flooded in January 2002, January 2003, at the end of November 2003, December 2004 and November 2005. These areas are shown in Appendix 1, map 5.
ii)    marshy/boggy areas
There are various marshy/boggy areas on the site. These are mainly on the eastern edge of the meadow near the Lumley Stream, in Lumley copse, just past the line of central willows dividing the North Meadow from the Central Meadow (which might possibly be a spring) and in the SE corner.
The Lumley Stream is tidal, so when there is a high tide coupled with strong winds and high rainfall, the Lumley wet area gets flooded. Under these weather conditions, the area flooded extends quite a distance onto the Central Meadow. The whole SE corner of the Central Meadow was inundated at the beginning of November 2005.  These areas are shown in Appendix 1, map 5.
All the main footpaths used to get very muddy especially in the winter but BMCG relaid them with path gravel between 2003 and 2005.
c) Ground water levels
It was not possible to obtain any information on ground water levels or on the presence of springs because the Environment Agency have not had any bore holes in this area. But a spokesperson for the Environment Agency said that the water levels are likely to be quite high because most of the area is less than 5 m above mean sea level. When planting a tree in the Central Meadow (area C) in October 2005, it was noted that the groundwater level was about 35 cm below the surface.

3.2.1.3    Geology

The site is in a river valley bottom. Solid geology consists of Reading Beds in the south and London Clay in the north both are from the Tertiary period. Surface geology is formed by estuarine alluvium deposits.

3.2.1.4 Geomorphology

The site is flat, divided into a number of areas by raised embankments.
Most of the site is only about 2-3 m above Mean Sea Level (MSL).
It is not known when the southern embankments in Palmers Road copse to retain water in the old linear millpond were constructed but it must have been at least 300 years ago. These old embankments were extended in 1994/95, by constructing approx. 1.50 metre high man-made embankments which continued north along the eastern and northern banks of the River Ems. In addition, a raised path was constructed between the Central Meadow and the South Meadow in an east-west direction to form a Causeway. The construction of this new embankment means that most the site is no longer flooded by the river apart from the South Meadow which functions as a balancing pond in the winter when the water level in the River Ems gets too high and the river water is allowed to flow into this area and flood it.
There does not seem to be any substantial erosion of the riverbank apart from that caused by human activity.  

3.2.1.5    Soils

Most of the main area of meadowland is very fertile as evidenced by the extent of the tall herbs, such as Common Nettle, Hemlock Water-dropwort, Hogweed and several coarse grasses. A lot
of useful information was obtained when doing research for the ‘Brook Meadow Through the Ages’ exhibition held in April 2005. This information helps to explain the present nature of the soil.
·    The northern meadow used to be a water meadow which was flooded regularly until the early part of the 20th century.
·    The whole meadow was regularly grazed by cattle and horses until about 1970.  
·    This means that alluvial deposits from flooding will have built up as well as black loam due to the build up of organic matter.
·    One of the reasons for the high fertility is that the site was neglected and the vegetation left to die down each year for at least a period of 10 years (between 1990 and 2000).
·    As part of the construction work for the A27(T) to the north in the late 1980’s, the surface layer of soil in the central and northern meadows was scraped off and used to build the embankment and raised path to prevent the meadow from being flooded by the River Ems. It is not known if any soil was brought in from elsewhere.
·    It is only since 2001 that the main meadow area has been cut and the arisings removed with the aim of reducing soil fertility.
a) Types of soil
In addition to the above historical information, information about soil types has been obtained when planting trees and when taking pH measurements.
The various soil types are summarised in the following table:

Area	Name	Soil
A	Palmers Road copse	Mixture of alluvium and loam near river, more loamy away from river. This area is regularly inundated.
B	South Meadow	Black loam in South, sandy loam in North. This area is regularly inundated especially the SE corner. Whole area can be flooded in winter.
C	Central Meadow	Sandy loam, waterlogged in some areas, area west of Lumley Stream may be inundated at spring tides
D	North Meadow	Areas of black loam, silty clay loam and paler loam with sticky silty clay subsoil being brought to the surface by moles. Waterlogged in some areas
E	Lumley Road copse	Black loam, waterlogged in some areas
F	Seagull Lane patch	Mixture of sandy loam and coarse gravel
G	Lumley Stream	Alluvium and silt in pools with areas of stones and coarse gravel
H	River Ems	Alluvium and silt in pools with areas of stones and coarse gravel

It was not possible to ascertain the depth of the soil over the site. However, when planting some trees on the edges of the Lumley wet area (eastern part of Area C) in November 2004, it was noted that the depth of black loam was about 20-30cm with either a very stony clay-like subsoil, or estuarine alluvium deposits (quite smelly).
b) Soil pH
pH is a measurement of the acidity or alkalinity of soil. A pH of between 4 and 6.5 is acid, a pH of between 6.5 and 7.5 is neutral and a pH between 7.5 and 14 is alkaline. In January 2006, pH measurements were taken at 20 locations covering 6 areas of the site using the group’s newly purchased electronic pH meter (locations and pH values are shown in Appendix 1 map 6, ).
The results are given in the following table according to area.

Area	pH (range and average)	Acid/Neutral/Alkaline
Palmers Road copse (A)	7.63-7.83 (average = 7.76)	Slightly alkaline
South Meadow (B)	7.61-7.77 (average = 7.69)	Slightly alkaline
Central meadow (C)	6.73-7.90 (average = 7.57)	Neutral to slightly alkaline
North Meadow (D)	7.79-8.23 (average = 7.95)	Slightly alkaline
Seagull Lane patch (F)	7.77-7.79 (average = 7.86)	Slightly alkaline
River Ems (H)	7.9-8.03 (average = 7.94)	Slightly alkaline

The results show that most of the site is slightly alkaline, the highest alkaline measurement (pH of 8.23) was recorded in the eastern part of the North Meadow (in the Rowan plantation). As expected, the River Ems being a chalk river is also slightly alkaline (average pH of 8.03). The only location with a neutral pH (6.73) is the sedgy area just north of the Causeway. This was the lowest pH recorded which means that none of the locations gave acid measurements.
It should be noted that these pH measurements were taken after 5 successive years of management. No pH measurements were taken when the group took over the management of the site in 2000. Nor have any measurements been taken of either the salinity or fertility of the soil.