Forge Dam


Forge Dam is a popular destination for families and walkers. It provides a beautiful place to stop for a break to admire the views across the Dam, or to enjoy a drink or something to eat from the cafe. There is also a children's playground with a much talked about slide built into the hill side.

Forge Dam Restoration Project

The Dam itself is silting up very quickly and the Friends of the Porter Valley are working hard on a restoration project which will see the removal of the silt, reduce the size of the island, and install a submerged wall which will prevent the dam from silting up again. Scroll down to find out more about the latest developments in this project.

To find out more about the history of Forge Dam, or the restoration proposals please click the links here.

Forge Dam Restoration Works Updates

May 2021


With Sheffield City Council we have procured Sanctus Ltd to undertake the restoration works at Forge Dam through to completion.  They are being appointed initially for final site investigations, design and costing.

Sanctus wrote this about themselves in their tender response: 

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Sanctus are an award-winning environmental consultant and contractor working on some of the most challenging brownfield and blue / green infrastructure programmes and projects across the country. We have successfully transformed former power stations into renewable energy hubs, built a new village in a former abandoned quarry saving hundreds of acres of green belt in the process, turned thousands of tons of asbestos filled soils into wildflower meadows, created new wetland habitats, daylighted water courses, removed barriers to migratory fish and reprofiled water courses creating space for water and wildlife. Over the past two years we have been shortlisted for more than 20 awards including being named the Best Green Business in the 2020 Business Leaders Awards in recognition of our exceptional environmental works. Over the last 18 years we have completed almost 4000 environmental engineering / improvements projects, and we are especially proud of our impressive catalogue of work with Rivers Trusts, Wildlife Trusts and Local Authorities….We are committed to working in collaboration and as such only seek to work on projects that will have a positive impact on people, wildlife and the local environment. We were hugely impressed by the ambition, philosophy, and commitment of both the Friends of the Porter Valley Group and also Sheffield Council when we visit the site early in 2021.


The Forge Dam Heritage & Habitat Improvement Project


The thermometer here shows how much the Friends of the Porter Valley have raised to date from small donations and events, including £70,000 from Council Section 106 money (under this scheme new property developments have to give money for community good). 

Our regular community events of the Annual Duck Race, and Christmas Fair help to raise useful amounts whilst having a great time. However we urge visitors to pop their spare change into the collection bottle on the counter in the Forge Dam Café or into the green charity buckets which will be around on conservation work days twice a month.

Alternatively you can make an Online Donation here;

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In January the Council approved the restoration proposals, including:

'silt removal, the insertion of a discreet wall to direct the brook over the spillway and address the longstanding problem of silting, and the creation of an attractive open body of water with a variety of depths, a reconfigured island and planting on perimeter banks in order to  improve the habitat for wildlife'.


Practical desilting is now planned to start in the autumn and in the intermediate months the practical foundations for the restoration will be laid, meaning that a partnership agreement will be signed by both parties, FoPV will donate £267,000 to the Council, specifications and tenders for the various specialist works will be issued, and the habitat improvement plans will be drawn up.


In May, ‘Sanctus Ltd‘, an environmental engineering specialist was  appointed. Their team has excellent relevant experience of projects like ours, were named the Best Green Business in the 2020 Business Leaders Awards and will deliver the restoration through to completion. We still expect the major works to start autumn/winter subject to sufficient funding, and any rerouting of paths will be signposted 12 weeks ahead of that date. So more news to come!


We appointed a specialist consultant to determine the precise amount of silt to be extracted from the pond and where this can be disposed of within the confines of “waste management regulations”, The bid was submitted in late spring.


The Forge Dam Heritage and Wildlife Improvement committee consisting of FoPV and Council representatives was boosted by two new members from the City Council, who have expertise on waste management and funding bid preparation.


In March we were able to empty the old Silt Trap and we intend to monitor how effective it is.

An anonymous donation of £100,000 was promised in November and the Council and FoPV set in motion the restoration action. A December sale of wreaths, Calendars, Christmas cards and other FoPV merchandise raised just over £3000


By the end of the year funds stand at just over £335,500.


FoPV volunteers continued landscape  improvements on the overgrown island and the brook channel.


The FoPV duck race raised over £11,000


FoPV cleared the first stage of the bidding process for a medium sized Heritage Lottery Fund grant in August.


Work started on the full application for up to £200,000


The final bid will propose more wildlife / habitat improvement, more public information on, and involvement in, the heritage and natural history of the area. 


By the end of the year a partnership agreement with the Council,  a revised FoPV Constitution, and a fresh User Survey were in place.


By the end of the year funds stand at just over £255,000.


FoPV Work is undertaken in de silting the main river route to prevent any further increase in silt deposition.


Sheffield Council Steering group planning application is submitted and no new application to the Environment Agency needs to be made, though an application to Sheffield City Council must be made for the area above the spillway.


The environmental impact statement completed.


FoPV FoPV conservation group clear the last part of the new channel so that the water can flow freely through the channel.


FoPV The technical proposals for steering the Porter Brook and disposing of the silt submitted to a Council programme board.


FoPV Received planning permission for the proposals.


FoPV By the end of the year funds stand at over £217,000


Sheffield Council approve the technical proposal to introduce a ‘training’ wall. 


With Sheffield Council approval and over 50% of the target funds raised, FoPV start to draft submissions to major donor agencies.


The FoPV duck race raises over £10,000 for a second time.


FoPV Workdays in December concentrate on clearing the island of self set trees, and plans are drawn up to start de silting the main river route to prevent the sudden increase in silt deposition.


FoPV By the end of the year funds stand at over £200,700


FoPV commit funds for a hydro geo morphological survey to consider the problem of the build-up of silt, identifying the required long term and sustainable solution.

The channelling of the brook to improve its flow through the dam would be possible by introducing a ‘training’ wall along its original route. This would allow sediment to continue with the river rather than settle in the dam. The money needed as a result was recalculated to be £370,000.


FoPV engage consultants to analyse the silt so that decisions about its disposal could be made.

Results of this reveal the presence of small levels of hydrocarbons and cadmium raising questions about how the silt can be safely disposed of.


Local scout group use their community week to help tidy up the Cafe area and develop the gardens.


FoPV By the end of the year funds stand at just over £161,000 (Inc. section 106 money).


The embankment was reseeded with grass and wild flowers.


Technical solutions to removing the silt begin and consultants appointed to give a professional opinion.


The FoPV Duck Race raises over £10,000.


By Year end the funds stand at just over £143,000 (Inc. section 106 money)


Sheffield Council allocates £70k to the restoration fund from section 106 agreements with local developers.

A section 106 agreement is an agreement between a developer and a local planning authority about measures that the developer must take to reduce their impact on the community. It forms a section of the Town And Country Planning Act 1990.


FoPV volunteers install Ecogrids (environmentally friendly ground reinforcement) to protect the grassed area at the foot of the embankment.


FoPV volunteers undertake landscape works and continue to open up the area to the sunshine.


More trees removed above the spillway and the embankment.


FoPV volunteers develop the gardens around the Café area. 


By year end the funds stand at just over £127,000 (Inc. section 106 money).


FoPV volunteers undertake clearance of the area outside the Café, removing trees and scrub.


FoPV introduce autumn and winter fairs for the community to help raise funds.


By the end of the year funds stand at over £40,000


Public Consultation on recommendations take place at Forge Dam Café and Sheffield Council approve a Master Plan proposal to remove the silt from the dam, and retain a smaller island. 

It is also stipulated that the management of future build-up of silt must be sustainable, and estimate the cost of desilting and landscape improvements to be £360,000.

The Plan does NOT include the return of rowing boats to the dam.


It was agreed that the silt could not be removed until the money for the whole project had been raised.


With no identifiable Council budget for these works, FoPV launch the Forge Dam Restoration Project and fundraising starts in the spring.


Money to be raised by collecting at talks, walks, and running community events, and from the Annual Easter Duck Race which was previously used to raise money for the Shepherd Wheel Restoration.


FoPV launch their annual calendar to help raise funds.


Sheffield Council engage consultants in Landscape Design and Management of old industrial millponds (dams) to produce recommendations to restore Forge Dam.


Unlike the other millponds in the Porter Valley, Forge Dam ‘blocks’ the river and takes the full flow of the brook, making it prone to silting.


Two previous attempts had been made in the 1970s and ‘80s to desilt the dam, with the latter project creating the island we see today and the installation of a silt trap just upstream from the dam. Unfortunately the planned bi-annual clearance of the silt deposited in it fell victim to early Council cuts and was rarely undertaken.  The opening of the original shuttle on the spillway to flush out silt had already ceased.


Sheffield Council is made aware of the poor state of the Forge Dam area via a public petition.