Broads Restoration
Broads restoration aims to recreate clear water with healthy aquatic plant growth which provides a habitat for wildlife. The Broads Authority embarked on a broads restoration programme in the 1970s to prevent further reduction in water quality and damage to the fragile aquatic habitats. It was thought that controlling the phosphorus (a nutrient which can cause enrichment of water) entering the waterways might trigger the return of clear water. Phosphorus control was mainly acheived by increased treatment of effluent from sewage treatment works. However, further environmental and ecological research revealed that restoration was more complex than simply reducing phosphorus. Restoration requires a step by step solution before clear water and submerged plant species can be re-established in the longer term.
Techniques used to improve water and habitat quality within the Broads have included:
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Phosphorus control - the final stage of treating sewage to remove dissolved phosphates prior to discharge of the cleaned effluent into the Broads waterways
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Suction dredging - removing mud from the bottom of the lakes and rivers - Barton Broad is the largest broad which has been dredged in this way
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Removal of fish, or biomanipulation - a way of giving water fleas a chance to graze the algae to low levels and clear the water
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Reduction of nutrients, including those from agricultural sources - achieved through adopting environmentally sensitive farming practices in the land surrounding the Broads rivers
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Educating boat users about environmentally friendly boating practices
Restoring degraded broads always requires the reduction of nutrients entering the water. When nutrient levels are low, few algae can grow which means the water is less cloudy. Nutrient reduction is achieved by reducing inputs from sewage works or agriculture. Nutrients can also be released from the mud at the bottom of the broads. Where the mud contributes significantly to the nutrient input, removing the mud helps reduce the amount of nutrients available.
Often the animals in the Broads need a helping hand to recover from the years of algae rich, cloudy water. Water fleas like to graze on algae, but large populations of small fish, mainly roach, keep their numbers down by feeding on them. So in order to increase the amount of algae eaten by water fleas, the small fish need to be removed. This technique of stimulating the natural biological processes in a lake is called biomanipulation.
Step by step: the story of broads restoration (pdf document) [67kb]
A new strategy for lake restoration in The Broads sets the future direction and priority for the restoration of broads. These restoration priorities reflect the need to continue to enhance the ecological quality of broads and for the first time recognise the value of benefits of restoration for people (ecosystem services). In addition the strategy links the risks of climate change with prioritising investment for conservation.
Lake Restoration Strategy (pdf document) [1710kb]
Appendix 1 - Issues Affecting Lakes (pdf document) [272kb]
Appendix 2a - Prioritisation Summary (pdf document) [36kb]
Appendix 2b - Prioritisation Designated Sites (pdf document) [44kb]
Appendix 2c - Prioritisation Non-Designated Sites (pdf document) [28kb]
Appendix 2d - Prioritisation Key (pdf document) [16kb]
Appendix 3 - Review of Sediment Removal (pdf document) [980kb]
Appendix 4 - Review of Biomanipulation (pdf document) [1075kb]
Appendix 5 - History of Lake Restoration (pdf document) [96kb]
Appendix 6 - Ecosystem Services (pdf document) [216kb]
Appendix 7 - Maps (pdf document) [5468kb]
Lake Restoration Strategy Annual Action Plan
The first annual Action Plan to be produced from the Lake Restoration Strategy is available for 2009/10, which includes an update of restoration projects completed in 2008/09. The Plan gives an update on completed broads restoration projects and outlines the priority actions for the coming year. It is a 5 year action plan, with a more detailed breakdown of the current year’s work. To view the pdf click here.
