Timperley Brook, Altrincham, Greater Manchester: Assessment of options for ecological improvement
Date: September 2021
For: Environment Agency
Type: Catchment plan and options assessment
Timperley Brook is a tributary of Sinderland Brook, located South of Manchester and West of Manchester Airport. It scores very low in all the criteria used to assess its quality, except for one reach, which has been restored. RRC suggest continuation of collection of baseline data and information on reaches and tributaries not surveyed in this report.
Excessive fine sediment is a detrimental factor in the catchment. Specific sources have not been identified and quantified, but the agricultural areas are potentially significant sources. RRC suggest undertaking a study to identify specific sediment sources and work with landowners/future developments to reduce sediment input.
Options have been assessed based on capability to improve the catchment condition, specifically with respect to the most significant catchment impacts - fine sediment accumulation, a lack of in-channel forms, and poor longitudinal and floodplain connectivity. RRC suggest continuing to assess options against these catchment impacts as more data and information is collected.
The options that will result in the greatest catchment improvement are thought to be at Timperley Brook flood basin and Navigation Road Park. There is a restored reach which provides an example and template for future restoration works. RRC suggest working with geomorphologists, ecologists, flood risk engineers and local organisations to develop a project plan for Timperley Basin using the lessons learnt from the Sinderland Brook restoration.
Significant barriers to migratory species are present in the catchment, including a weir. There are also several other structures (such as bridges) that could pose a potential barrier to species. We suggest assessing all the potential barriers in the catchment to understand the pressures and impacts on longitudinal connectivity.