The company's Branch Out scheme, was set up in 2013 to support local community groups, organisations and individuals with projects to benefit the natural environment.
Projects that have received funds from the initiative range from the restoration of some of the most threatened habitats, to creating new outdoor environments - including tree planting and supporting endangered species.
Suffolk Wildlife Trust's Carlton Marshes project, which is home to some of the UK's rarest wetland wildlife, and the creation of new outdoor areas in Thurrock for St Luke's Hospice are just some of the local projects that have benefited from the scheme over the years.
The money that Essex & Suffolk Water has donated since the scheme launched has contributed towards other match-funding sources to secure a £10 million wider partnership investment to benefit the natural environment, wildlife and local communities.
Essex & Suffolk Water's Conservation and Land Manager, Miranda Cooper, said: "Our Branch Out programme is making a positive difference and helping local projects reconnect habitats for the benefit of communities and wildlife.
"This will all help to build resilience, which is essential for supporting a healthy natural environment and for us to supply clear, great tasting drinking water.
"It's fantastic we can support local groups, organisations and charities in helping to make a difference to the communities we serve."
For more information about the company's Branch Out scheme, visit: https://www.nwg.co.uk/responsibility/environment/branch-out-funds/