Our Dry Weather Plan South East Water’s 2021 draft drought plan Appendix L: SSSI Assessment (site of special scientific interest source pathway receptor analysis for drought permit options) March 2021 South East Water Rocfort Road Snodland Kent ME6 5AH Drought Plan | March 2021 Contents 1.1 Groundwater drought permits - site of special scientific interest source pathway receptor analysis 3 1.1.1 Halling No. 8 - site of special scientific interest source pathway receptor analysis 3 1.1.2 Balcombe- site of special scientific interest source pathway receptor analysis 5 1.1.3 Tangier / Chasewood - site of special scientific interest source pathway receptor analysis 6 1.1.4 Southlands / Oaklands - site of special scientific interest source pathway receptor analysis 8 1.1.5 Hackenden - site of special scientific interest source pathway receptor analysis 10 1.2 Surface water - Site of special scientific interest source pathway receptor analysis 11 1.2.1 RIVER OUSE Drought Plan - SSSI Source Pathway Receptor Analysis 2020 11 1.2.2 RIVER CUCKMERE - site of special scientific interest source pathway receptor analysis 14 Annex – Assessment of the hydrological links between the River Cuckmere and the West Dean Brooks. 19 2 Drought Plan | March 2021 1.1 Groundwater drought permits - site of special scientific interest source pathway receptor analysis In support of the assessment of potential effects associated with the drought permit it has been assumed that: • All appropriate infrastructure is in place at the source • Pump testing will have been undertaken and used to confirm the extent of any surface water drawdown and inform the need to re- scope this assessment with respect to potential groundwater effects • Abstracted water meets all quality criteria associated with both Environment Agency consenting requirements and requirements for potable supply • All abstracted water is transferred to supply via existing pipe works 1.1.1 Halling No. 8 - site of special scientific interest source pathway receptor analysis PRESENCE OF HYDROLOGICAL / POTENTIAL FOR DISTANCE FROM WATER SENSITIVE SSSI NAME REASON FOR NOTIFICATION HYDROGEOLOGICAL SIGNIFICANT ABSTRACTION (km) FEATURES OF PATHWAY IMPACT INTEREST Halling to Chalk grassland and beech 0.5 km NW NO Depending on distance NO Trottiscliffe woodland on chalk. Outstanding and elevation, there may Escarpment SSSI assemblages of plants and be a hydrological invertebrates. relationship. However, the habitats are typically found on freely draining soils and as such groundwater will not be a critical factor in their ongoing resilience and success. 3 Drought Plan | March 2021 Holborough to Floodplain habitat of the tidal 1.7 km SE YES This is possible because NO Burham Marshes Medway including reedbeds, of the presence of more SSSI open water, fen, grassland, permeable strata. However, the small scrub and quantity being woodland. Supports a wide abstracted is highly variety of breeding birds and is unlikely to have a also important for wintering drawdown cone wildfowl and waders. affecting surface habitats beyond 1km. This SSSI is located beyond this distance, with intervening tidal creeks and a hydrological/hydrological relationship will not be evident. Houlder & Sediments found provide 1.1 km SW NO This is possible because NO Monarch Hill Pits of the presence of more Lithostratigraphic/biostratigraphic SSSI permeable strata. evidence for environmental However, the small changes during the Late quantity being Devensian. abstracted is highly unlikely to have a drawdown cone affecting exposed geological features to the point where accelerated weathering occurs. 4 Drought Plan | March 2021 1.1.2 Balcombe- site of special scientific interest source pathway receptor analysis PRESENCE OF HYDROLOGICAL / POTENTIAL FOR REASON FOR WATER SENSITIVE DISTANCE FROM SSSI NAME HYDROGEOLOGICAL SIGNIFICANT NOTIFICATION FEATURES OF ABSTRACTION (km) PATHWAY IMPACT INTEREST Worth Forest SSSI Ancient Wealden ghyll YES 1.5 km N This is possible because NO woodland which is an of the presence of more example of a base-poor permeable strata. springline alder wood, However, the small supporting assemblage quantity being of water dependant abstracted is highly plants. unlikely to have a drawdown cone affecting surface habitats beyond 1km. This SSSI is located beyond this distance and a hydrological/hydrological relationship will not be evident. Cow Wood & Harry’s Ancient woodland with YES 1.9 km SW This is possible because NO Wood SSSI several moist ghylls that of the presence of more have a moist warm permeable strata. microclimate favouring However, the small ‘Atlantic’ bryophytes and quantity being ferns. Ponds are also abstracted is highly present which are unlikely to have a important for dragonflies. drawdown cone affecting The SSSI supports a surface habitats beyond 1km. This SSSI is 5 Drought Plan | March 2021 rich community of located beyond this breeding birds. distance and a hydrological/hydrological relationship will not be evident. 1.1.3 Tangier / Chasewood - site of special scientific interest source pathway receptor analysis PRESENCE OF HYDROLOGICAL / POTENTIAL FOR REASON FOR WATER SENSITIVE DISTANCE FROM SSSI NAME HYDROGEOLOGICAL SIGNIFICANT NOTIFICATION FEATURES OF ABSTRACTION (km) PATHWAY IMPACT INTEREST Eridge Park SSSI Parkland and ancient YES 1km SW NO. ABSTRACTION NO woodland particularly IS CONSIDERED TO rich range of epiphytic BE FROM A lichens. Varied habitats CONFINED SOURCE also support diverse insect and bird communities, and it is recognised as being nationally important for dragonflies. 6 Drought Plan | March 2021 7 Drought Plan | March 2021 1.1.4 Southlands / Oaklands - site of special scientific interest source pathway receptor analysis PRESENCE POTENTIAL OF WATER HYDROLOGICAL / REASON FOR DISTANCE FROM FOR SSSI NAME SENSITIVE HYDROGEOLOGICAL NOTIFICATION ABSTRACTION (km) SIGNIFICANT FEATURES PATHWAY IMPACT OF INTEREST SOUTHLANDS Shortheath Common Mires and bog habitats, YES 1.5 km N NO. ABSTRACTION IS NO SSSI (part of Shortheath together with dry heath CONSIDERED TO BE Common SAC) and bog woodland. FROM A CONFINED Significant populations SOURCE of invertebrates including important assemblages of dragonflies and butterflies. Wick Wood and Woodland with slopes, NO 0.9 km NW NO. ABSTRACTION IS NO Worldham Hangers rich in vascular plants, CONSIDERED TO BE SSSI (part of East bryophytes and old FROM A CONFINED Hampshire Hangers pollards. SOURCE SAC) Coombe Wood and The Woodland with slopes, NO 0.9 km NW NO. ABSTRACTION IS NO Lythe SSSI (part of East rich in vascular plants, CONSIDERED TO BE Hampshire Hangers bryophytes and old FROM A CONFINED SAC) pollards. SOURCE 8 Drought Plan | March 2021 Woolmer Forest SSSI Wet and dry YES 1.7km SE NO. ABSTRACTION IS NO (part of Woolmer Forest heathland, valley bogs, CONSIDERED TO BE SAC/SPA) broad FROM A CONFINED SOURCE leaved and coniferous woodland, permanent grassland and open water. The only site in Britain known to support all twelve native species of reptiles and amphibians and supports a nationally important heathland flora, with associated birds and invertebrate fauna. OAKLANDS Binswood SSSI Habitats include acidic NO 0 NO. ABSTRACTION IS NO poorly CONSIDERED TO BE FROM A CONFINED drained unimproved SOURCE pasture with scattered old oaks and beeches, areas of denser woodland with a sparse shrub layer and ground flora, and former encoppicements now 9 Drought Plan | March 2021 open to grazing. Very rich invertebrate assemblage. Wick Wood and Woodland with slopes, NO 0.9 km NW NO. ABSTRACTION IS Worldham Hangers rich in vascular plants, CONSIDERED TO BE SSSI (part of East bryophytes and old FROM A CONFINED Hampshire Hangers pollards. SOURCE SAC) Shortheath Common Mires and bog habitats, YES 0.4 km SE NO. ABSTRACTION IS NO SSSI (part of Shortheath together with dry heath CONSIDERED TO BE Common SAC) and bog woodland. FROM A CONFINED Significant populations SOURCE of invertebrates including important assemblages of dragonflies and butterflies. 1.1.5 Hackenden - site of special scientific interest source pathway receptor analysis PRESENCE OF HYDROLOGICAL / POTENTIAL FOR REASON FOR WATER SENSITIVE DISTANCE FROM SSSI NAME HYDROGEOLOGICAL SIGNIFICANT NOTIFICATION FEATURES OF ABSTRACTION (km) PATHWAY IMPACT INTEREST 10 Drought Plan | March 2021 NO SSSI RECORDED WITHIN AT LEAST 2KM OF PROPOSED ABSTRACTION. GROUNDWATER SOURCE IS CONSIDERED TO BE A HIGHLY- CONFINED SOURCE OF GROUNDWATER. NO SIGNIFICANT IMPACTS PREDICTED. 1.2 Surface water - Site of special scientific interest source pathway receptor analysis 1.2.1 RIVER OUSE Drought Plan - SSSI Source Pathway Receptor Analysis 2020 PRESENCE DISTANCE OF WATER HYDROLOGICAL / POTENTIAL FOR FROM SSSI NAME REASON FOR NOTIFICATION SENSITIVE HYDROGEOLOGICAL SIGNIFICANT ABSTRACTION FEATURES PATHWAY IMPACT (km) OF INTEREST Asham Quarry Geological. Key site for quaternary 8km from point of NO NO – no hydrographical NO studies, key reference site for abstraction connection indicated using biostratigraphical and (downstream) EA flood zone and surface lithostratrigraphical evidence. water extent mapping. Primarily geological. It is a nationally 15km from point NO NO – Coastal site, no NO important reference section for the of abstraction hydrographical connection Brighton to Newhaven upper Cretaceous. Locally important (downstream) indicated using EA flood Cliffs colony of breeding seabirds, a zone and surface water diverse community of beetles, and extent mapping. pockets of unimproved chalk grassland. Buxted Park Biological.