Hogsmill River

Catchment partnership vision

Our vision is for the Hogsmill to be a clean river, rich in biodiversity, that is seen as a valuable resource for an engaged local community.

Related websites

Find out more about the activities and ambitions of this catchment partnership and how you can get involved to help improve the water environment in the catchment.

Catchment challenges

Current challenges identified by partnership

  • Changes to the natural flow and water levels

    Over abstraction can cause low flows in the Hogsmill in the summer months

  • Pollution from waste water

    Combined Sewer Overflows (CSO) frequently discharge in the upper reaches of the river

  • Physical modifications

    Heavily modification, as a result of an industrial past and urban nature of catchment, impact significantly

Wider water environment challenges identified by partnership

  • Nature Recovery, protect and enhance rare habitats including chalk streams

    As a globally rare chalkstream, the Hogsmill needs to be afforded greater protection from pollution and low flows

  • Build environmental resilience and adaptation to climate change

    Extreme drought and rainfall events threaten the catchments species and habitats, investment is needed to facilitate adaptation

  • Reduce storm overflows and drainage system incidents

    Wastewater and drainage are significantly impacting water quality in the Hogsmill, especially in the upper reaches where low flow mean less dilution

  • Support Nature Recovery Network and Local Nature Recovery Strategy

    Opportunities within the catchment to enhance sites and riparian zones and improve connectivity

  • Protect and restore healthy soils and nutrient balance

    Reduction in sediment input from agricultural areas

  • Connecting communities with nature

    Provide more opportunities for education and engagement, targeting underrepresented groups

Future challenges predicted by partnership

  • Changes to the natural flow and water levels

  • Pollution from waste water

  • Physical modifications

Future challenges predicted by Environment Agency

Future challenges in 2050

  • Pollution from Towns Cities and Transport
  • Invasive Non-native Species
  • Changes to the Natural Flow and Water Levels

Emerging challenges

  • Changes to the Natural Flow and Water Levels
  • Pollution from waste water
  • Pollution from Towns Cities and Transport

Partnership success highlights 2016 to 2021

Since 2016, the Hogsmill Partnership has achieved a wide range of improvements to the river and its catchment, benefiting both people and wildlife. This includes:

  • improvements to public access with open green spaces created adjacent to the river, including interpretation boards, way-marking and improvements to path surfacing
  • citizen science projects have helped to identify sources of pollution, record invasive non-native species and monitor populations of eels and invertebrates
  • volunteers have given thousands of hours to assist with habitat management, river restoration projects, removal of litter and a water vole re-introduction project
  • partners continue to work collaboratively to address the removal of invasive non-native species within the catchment, specifically Himalayan balsam which is widespread
  • continued management of green spaces for the enhancement of biodiversity including conservation grazing, coppicing, hedge laying, tree planting and grassland management
  • barriers to fish passage along the Hogsmill have been addressed by the installation of rock ramps, fish passes and full weir removals
  • large-scale river restoration work in the Hogsmill Local Nature Reserve and the Raeburn Open space has restored natural processes and enhanced habitat diversity through the removal of concrete and toe-boarding, installation of berms and woody material, and reshaping of the river channel.

Partnership development plans

We want to see the development of the Hogsmill action plan and continued partnership working to deliver improvements to water quality and low flows. A joined up, catchment-wide approach including community involvement is needed for tackling invasive non-native species (INNS), specifically Himalayan balsam which is widespread and abundant.

Partnership priority actions and measures for 2022 to 2027

  • Confident

    Enhancement/no deterioration measures in 2020-2025 Water Industry National Environment Programme

    Reason for measure
    Control or manage point source discharges
    Delivery mechanism
    Confirmed water industry national environment programme 2020-2025
    Location
    Hogsmill
  • Confident

    Low Flow Investigation

    Reason for measure
    Control or manage abstractions
    Delivery mechanism
    None identified
    Location
    Hogsmill
  • Confident

    Citizen Zoo Water vole reintroduction at Hogsmill Sewage Treatment Works

    Reason for measure
    Mitigate the impacts on ecology from physical modifications in modified waters
    Delivery mechanism
    None identified
    Location
    Hogsmill
  • Confident

    Habitat improvement at Hogsmill Sewage Treatment Works

    Reason for measure
    Mitigate the impacts on ecology from physical modifications in modified waters
    Delivery mechanism
    Confirmed water industry national environment programme 2020-2025
    Location
    Hogsmill
  • Confident

    Volunteer initiatives: Outfall safari, Riverfly Monitoring Initiative, INNS species surveying, river clean-ups

    Reason for measure
    Manage modified habitats
    Delivery mechanism
    Voluntary initiatives
    Location
    Hogsmill
  • Confident

    Hogsmill invasive non-native species (INNS) strategy and management of Himalayan balsam

    Reason for measure
    Control or manage invasive non-native species
    Delivery mechanism
    Other local funding
    Location
    Hogsmill
  • Less certain

    Chamber Mead wetland

    Reason for measure
    Control or manage urban diffuse pollution
    Delivery mechanism
    Other local funding
    Barriers to delivery
    Securing funding
    Location
    Hogsmill
  • Less certain

    Kingsmeadow weir removal

    Reason for measure
    Mitigate the impacts on ecology from physical modifications in modified waters
    Delivery mechanism
    Potential future water industry programme
    Barriers to delivery
    Uncertainty around scope and timeframe, additional funding required
    Location
    Beverley Brook (Motspur Park to Thames) and Pyl Brook at West Barnes
  • Less certain

    Logs in Hogs

    Reason for measure
    Mitigate the impacts on ecology from physical modifications in modified waters
    Delivery mechanism
    WEIF Water Environment Improvement Fund
    Barriers to delivery
    Uncertainty around funding and timeframes for delivery
    Location
    Beverley Brook (Motspur Park to Thames) and Pyl Brook at West Barnes