This was the second phase of a project aimed to prevent further deterioration of water quality along a 350m section of Moston Brook. In order to try and improve water quality, an evidence and measures study was undertaken - led by the Environment Agency. Our partners have already undertaken some work to adddress some of the issues.
This particular project had objectives to address two specific issues:
- the first was to prevent surface water drainage from the industrial site.
- the second was to prevent surface water from formally landfilled areas entering Moston Brook.
As Moston Brook flows towards Mill Lane, it is bordered by one of several former landfill sites – Lancaster Sports Club fill so the creation of 130m length of flexi pave SUDS footpath to prevent surface water drainage from industrial area entering Moston Brook was proposed.
Creation of 220m area of drainage channels, levelled steps and accompanying swales created to prevent surface water drainage from former landfilled areas entering the brook.
Prior to the start on the site, at the wettest point closest to the proposed location of the SUDS footpath, a trial pit was excavated and surface water samples were taken. These were then analysed for a variety of contaminants as set out by the Water Framework Directive.
Several elements were present which posed threats to wildlife along this stretch of the corridor.
The project saw the objectives completed: primarily a stretch of land approximately ¼ mile long has been improved by alleviating surface water run-off and preventing run-off from flowing into the brook. A series of swales have been created to divert run off from entering the brook and instead into a series of balancing ponds.
Additionally, access was improved along the water course through constructing a new SUDS footpath along the mains stretch adjacent to a scrap yard; a rolled stone footpath and a series of steps.
Supporting Access Improvements
To help support the access improvements within Moston Brook, areas of fly tipping were also cleared.
Businesses at Mill Lane and Mill Street also gave their support. At the request of Oldham Council, two landowners paid for the installation of vehicular barriers to prevent further fly tipping. Another land owner also removed fly tipping on Mill Street at his own expense. An agreement with Oldham Council has been reached to remove fly tipping at the end of Mill Street which was not previously dealt with due to complications regarding land ownership. The council will also respond to future reports to ensure the area is maintained as a goodwill gesture.
The same pit was re-tested again after the post-construction of the SUDS footpath to determine any changes in the levels of the contaminants. It was expected that the construction of the SUDS footpath would reduce the levels of the analytes found in the pre-constructions phase; this is due to the contaminants being filtered as they passed through the SUDS path.
Findings of the samples
The second round of sampling indicated that the majority of the analytes has reduced since the SUDS system has been constructed; the only exceptions being Ammonia and Nitrate which rose by 0.03mg/l and 6.4mg/l respectively. Both of these increases remain below the 50mg/l specified by the EU Directive 2010.
This evidence suggests that the level of contaminates entering Moston Brook has dropped as a result of the intervention put in place during the course of the project.
The biggest benefit is the prevention of further deterioration of water quality in this section of the brook.
The project is also likely to contribute towards some of the failing elements, such as ammonia and dissolved oxygen which in 2013 were classified as bad and levels of invertebrates and phosphate that were poor. One of the reasons for failure in this waterbody is diffuse pollution which this project will help address.
The level SUDS porous footpath has multiple benefits – most importantly to absorb contaminated surface water. Other benefits also include a more aesthetic amenity, community involvement and improved biodiversity. It acts as a barrier and extends across the whole of the slope leading down from the industrial area. Due to the site being a former landfill area, we were unable, and unwilling, to use a standard unsustainable drainage system.
There will be biodiversity benefits related to the creation of the swale. Slope levelling and introduction of the swale will also assist with flood management.
Tips and lessons learnt
This project has demonstrated that green areas can be better protected with preventative as well as cultivating measures. The evidence and measure study assisted with raising the issues and has focused attention and actions to improve water quality in this water course.
By taking a proactive stance in working in partnership with non-agricultural businesses,
land owners, local residents and the council, such improvements have been made possible just through some simple changes in the ways of working. The delivery of a multi-use project, incorporating biodiversity and recreation benefits, has helped with this process.
The partnership model of working on a catchment scale (Irwell) and on a local level at Moston Brook has created good project ideas and good delivery mechanisms. Joint working has helped make this project happen.
The work to create the drainage channels was done in 2 tranches. Initial works were monitored for a while to be able to identify how they could be, and were, improved.
The project has highlighted other issues relating to waste water drainage at an adjacent site - this issue will be remedied by the new land owners. Oldham Council and Moston Brook Partnership will work with these site owners to facilitate a SUDS scheme related to the planned residential development adjacent to Moston Brook.
Habitat and access improvements.
Moston Brook before the habitat enhancement scheme.