The same land-use activities that create diffuse pollution also adversely affect the quantity of water, for example rapid runoff (loss of water) in storm events causing flooding, then drier periods following the rain. The land-use changes often also involve loss of valuable habitats and associated biodiversity; there is common cause to be made in seeking holistic solutions. Demonstrating the importance of all impacts, as well as the processes involved and the links between the various issues is a key step in driving progress to implement best practice mitigation measures across landscapes and catchments. We are keen to include interest from UNEP, IUCN and others too.

To develop the content of the report, impacts papers are sought in support of the initiative of the Specialist Group to develop up to date evidence on the importance of the issue, to be the factual basis for the IWA sponsored Land Use and Water Quality Report in 2019. This needs to involve fresh research as well as review papers on the following aspects:

• High level state of environment reports – estimating national extent and severity of diffuse pollution impacts on the water environment.
• Ecological impacts – case studies at any level, from river basin and coastal waters to local creeks and lakes, or particular species; ecosystems (coral reefs impacted by sediment from deforestation in tropical hinterlands, sea grass beds and freshwater lakes affected by eutrophication); key species of iconic importance (e.g. salmonids and pearl mussels affected by siltation in higher latitude rivers); direct toxicity and bioaccumulation studies (various hydrocarbons/urban drainage impacting freshwater biodiversity, pesticides and PCBs in birds and otters, emerging pollutants).
• Resource impairment and economic impacts – water quality of surface and groundwaters making them unfit for use by industries (e.g. food and drinks, textiles, and high quality paper businesses, needing to abstract clean water); recreational impacts (e.g. declines in salmon fishing, closure of bathing beaches, algal blooms/red tides and ‘clean’ reputation of water amenities damaged); risk of national/international regulatory actions, e.g. local beaches in breach of faecal pathogens standards, impacts on life and operations of hydro-power generation assets.
• Water utility impacts – statutory water quality requirements (e.g. for raw potable supplies, for surface water discharges from public networks, and impacts on performance of effluent treatment plans in relation to permits too); filtration plant running costs associated with algal blooms; reduction in life of reservoirs and other assets associated with influent sediment loads; blue-green/cyanobacteria toxins in potable supplies, or Cryptosporidium outbreaks, colour and flavours in potable supplies, including turbidity and hydrocarbons respectively etc.