Restoring Renfrewshire Rivers Update Report
Renfrewshire Council · 21 January 2026
Back to Infrastructure, Land and Environment Policy Board — 21 January 2026 and its agenda
Text extracted from the council's PDF. Layout and reading order may differ from the original.
Page 1
PUBLIC ___________________________________________________________________ To: Infrastructure, Land and Environment Policy Board On: 21 January 2026 ___________________________________________________________________ Report by: Director of Environment, Housing and Infrastructure ___________________________________________________________________ Heading: Restoring Renfrewshire’s Rivers Project Update ___________________________________________________________________ 1. Summary 1.1 The Restoring Renfrewshire Rivers project is an ongoing nature restoration project which was established by Renfrewshire Council in March 2024. This paper provides an update on the progress made to date and outlines the planned next steps for the project. 1.2 This project has been funded through the Nature Restoration Fund where Renfrewshire Council was awarded £350,000 from the Scottish Government. 1.3 The purpose of this project is to map the distribution and remove invasive non- native plant species (INNS) from 5 of Renfrewshire’s water courses; River Calder, Locher Water, Dargavel Burn, Old Patrick Water, and Sergeantlaw Burn. 1.4 A key aspect of the project is to embed support from a pool of volunteers, who are offered training in pesticide application to aid in the response of removing INNS plans. 2. Recommendations It is recommended that the Infrastructure, Land and Environment Policy Board: 2.1 Notes the progress made to date on the Restoring Renfrewshire’s Rivers project and planned next steps.
Page 2
PUBLIC 3. Background 3.1 In late 2023, Renfrewshire Council was awarded £350,000 of funding through the Scottish Government’s Nature Restoration Fund. This funding was allocated for the Restoring Renfrewshire’s Rivers project which has been underway since March 2024. 3.2 Mapping the distribution of invasive non-native plant species (INNS plants) through surveys has been carried out along 5 water courses; River Calder, Locher Water, Dargavel Burn, Old Patrick Water, and Sergeantlaw Burn. 3.3 The surveys highlight where INNS plants are located and targeted removal sessions can then be scheduled to tackle the identified species. This work is undertaken by the biodiversity officers as well volunteers who are supported by staff. 3.4 This project contributes to the Council’s Plan for Net Zero and nature recovery targets by reducing and removing INNS plants and replanting native tree and wildflower species which help reduce erosion, stabilise riverbanks, lock up carbon emissions, and benefit wildlife. 4. Restoring Renfrewshire’s Rivers Project: Progress Update 4.1 A total of 12.6km of watercourses were surveyed across 3 of the 5 project watercourses and their associated tributaries; 8km on the River Calder, 3.7km of Locher Water, and 0.9km of Sergeantlaw Burn. The distanced covered varied due to terrain, identified hazards, and drainage ditches. 4.2 Across the 5 watercourses the following INNS plants (of the 5 target species) have been recorded so far during surveys within headwaters: • River Calder- Pontic Rhododendron present by the Calder at Muirshiel Country Park • Locher Water- Himalayan Balsam present at East Midhouse Farm • Dargarvel Burn- No records yet of INNS plants • Old Parick Water- No records yet of INNS plants • Sergeantlaw Burn- Japanese Knotwood next to Gleniffer Road. Pontic Rhododendron present in the woodland near Nethercraigs Road. 4.3 The following INNS species were noted in the lower stretches of the project watercourses out with surveys. These were recorded from visuals whilst driving to sites, Google Streetview, or reported to the Biodiversity Officer from members of the public: • River Calder- Himalayan Balsam in large quantities, Japanese Knotweed, and American Skunk Cabbage.
Page 3
PUBLIC • Locher Water- Himalayan Balsam and Japanese/Bohemian Knotweed in large quantities. • Dargavel Burn- Himalayan Balsam and Japanese Knotweed. American Skunk Cabbage reported to be present within the BAE Systems Dargavel Site. • Old Patrick Water- Himalayan Balsam, Japanese Knotweed, Giant Hogweed. • Sergeantlaw Burn- Japanese Knotweed in an additional patch. 4.4 There were two sessions during 2025 to spray Japanese Knotweed strands with pesticide at the project watercourses. The first by the River Calder at Lochwinnoch where an area of 35sqm of Knotweed was sprayed; the second by the Sergeantlaw Burn at the Gleniffer Braes where an area of 40sqm of knotweed was sprayed. 4.5 Some sites have challenging terrain which makes surveying difficult such as Dargavel Burn. These sites will be surveyed using the drone once staff are fully trained on using and handling the drone. This should be in early 2026 following practical assessment. 5. Volunteer Progress 5.1 There is a total of 47 volunteers signed up to the project mailing list. During 2025, a total of 187 volunteer hours were used between May and September for Himalayan Balsam control work and site surveys. Three community / corporate volunteer sessions took place; Renfrewshire Youth Eco Volunteers group helped with a Himalayan Balsam control session by the River Calder at Lochwinnoch in June; Lochwinnoch Home Education group helped with a Himalayan Balsam control session by the River Calder at Lochwinnoch in July; Terumo Aortic did a session in the Lochwinnoch area which involved planting tree saplings, plug plants and a seed mix of native shade-tolerant plant species to shade out Himalayan Balsam seedlings. 5.2 15 Himalayan Balsam control sessions were carried out with volunteers in 2025. In total, over 33,000 Himalayan Balsam plants were removed or cut down during the volunteer sessions and staff visits. 5.3 2 Rhododendron control sessions were carried out by the River Calder at Muirshiel Country Park in early 2025 with volunteers. 19 Rhododendron bushes and 28 Sitka Spruce were treated. 3 further sessions took place in November and December 2025 with further sessions planned for 2026. 6. Project Successes in 2025 6.1 The project continued to work closely with the Council’s Countryside Rangers at Clyde Muirshiel and Gleniffer Braes to achieve effective INNS plant control. Continued work with RSPB at Lochwinnoch allowed for targeted surveys to be carried out and control of Himalayan Balsam and American Skunk Cabbage across the Calder catchment.
Page 4
PUBLIC 6.2 Himalayan Balsam control work has continued with evidence of recovery of native vegetation in areas which have had control work this year. 6.3 Japanese Knotweed spraying was carried out in 2025 for the first time. As this is highly impacted by the weather, it has been a success to have gotten this work underway. 6.4 There has been increasing promotion of the project with stronger internal exposure and interest within the council. Two information sessions were held over the summer period, which worked well, providing the opportunity to engage individually with small groups. 6.5 There has been an increase in group volunteers; Terumo Aortic and the Youth Eco group and Lochwinnoch Home Education group. This was due to increased exposure from the help of the Renfrewshire Climate Action Network. The aim is to build on this further in 2026. 6.6 Effective internal governance has helped aid the project with the establishment of Renfrewshire Council’s Sustainability Team, which the Biodiversity Officers are now part of. This has enabled new opportunities for promotion and input of new ideas. 7. Next Steps for 2026 7.1 Initially, the Restoring Renfrewshire’s Rivers project was considered as a three- year project. Since then, our learning has indicated that for the project to achieve long-term effective outcomes in terms of biodiversity and habitat recovery, sequestering carbon, training volunteers and working with project partners, it may need to continue in some form beyond the three years. For example, successful treatment of Japanese Knotweed will have to take up to five years of pesticide application and subsequent monitoring to ensure it does not grow back and to ensure recovery of the ground and of native plants. 7.2 Therefore, the project will continue to be delivered in 2026/27, building on the progress made so far. A plan for the next 12 months has been developed to support this activity. Following this period, a further review will take place to determine future plans for this area of work. 7.3 Continued INNS plant control work with increased Japanese Knotweed spraying and Himalayan Balsam and Rhododendron control work. This will be supplemented with increased biodiversity work such as tree planting and seed sowing. 7.4 Surveying work will continue along the project watercourses, including the surveying to be done using the drone as this training will be completed in early 2026.
Page 5
PUBLIC 7.5 Pesticide application training will continue to be organized for volunteers who would like to participate. This includes training for stem inject of pesticide for staff and volunteers. 7.6 There will be a focus on increasing exposure and engagement around the project to recruit volunteers (both internally and externally) to aid with the control work and surveys to be carried out this year. This will also include more targeted promotion at groups who may be interested, such as anglers. The aim is to increase working with volunteer groups and increase the pool of volunteers for the Restoring Renfrewshire’s Rivers projects and wider biodiversity work. 7.7 An engagement plan will be created for the Restoring Renfrewshire’s Rivers projects as well as wider biodiversity work. The aim is to begin with the check, clean, dry campaign to target water users to prevent spreading of invasive species. 7.8 The project team will continue to strengthen collaborative working opportunities with interested partners such as RSPB, Eadha Enterprises, other Council departments (Neighbourhood Services, countryside rangers etc), and the Green Action Trust. 7.9 A future update will be brought to the ILE board at the end of year three of the project in early 2027. Implications of the Report 1. Financial – None directly arising from this report. 2. HR & Organisational Development – None directly arising from this report. 3. Community/Council Planning – None directly arising from this report. 4. Legal - None directly arising from this report. 5. Property/Assets – None directly arising from this report. 6. Information Technology – None directly arising from this report. 7. Equality and Human Rights - The recommendations contained within this report have been assessed in relation to their impact on equalities and human rights. No negative impacts on equality groups or potential for infringement of individuals’ human rights have been identified arising from the recommendations contained in the report because it is for noting only. If required following implementation, the actual impact of the recommendations and the mitigating actions will be reviewed and monitored, and the results of the assessment will be published on the Council’s website.
Page 6
PUBLIC 8. Health and Safety – None directly arising from this report. 9. Procurement – None directly arising from this report. 10. Risk – None directly arising from this report 11. Privacy Impact – None directly arising from this report. 12. Climate Risk – The Restoring Renfrewshire Rivers Project contributes to the Council’s Plan for Net Zero and nature recovery targets and thus aims to positively reduce climate related risk. 13. Children’s Rights - None directly arising from this report. 14. COSLA Policy Position – This work aligns with COSLA’s current work alongside the Scottish Government in response to the climate emergency. List of Background Papers: None Authors: Danielle Leggett, Sustainability Lead Officer (Strategy) and Allan Russell, Biodiversity Officer