FiveRivers were brought in to create, monitor and maintain three critical ecological mitigation sites as part of the wider enabling works of Phase 1 of HS2.
4 ponds created
1 otter holt created
New grassland created
New woodland created
These three sites required the creation of compensatory habitat for otters, kingfishers, invertebrates, and bats in the form of new woodland, grassland, and wetlands. This project included considerable ruderal vegetation clearance and management, the construction of four lined ponds/scrapes, grassland reversion for wet and neutral grassland, stock fencing, installation of bat boxes, otter holt and king fisher nests, tree planting, translocation of notable wetland plant species into the newly created habitat and implementation of ongoing monitoring and management of vegetation and INNS for each of the sites.
During the management phase, biannual surveys of the translocated notable plants were undertaken to identify establishment. Monthly monitoring of the otter holt was conducted using camera traps to detect usage along with field sign surveys. The objectives of the site management plan (ESMP) were assessed against site conditions for instance the percentages species establishment of the grassland or survival rate of planted trees. An invasive species survey was conducted prior to works to identify the extent and need for precautionary working measures.
We worked collaboratively with the client team to ensure we got the best possible environment outcome at each site. The team developed techniques to re-use materials on site, and limit the amount of vehicle movements in and out. This not only limited disruption but also reduced the project carbon footprint.
In addition to our original scope we worked with the client to translocate several notable wetland plant species from a nearby affected site.
The mitigation sites, although looking very bare when first finished very quickly established to provide outstanding habitat. It was vital that these sites we’re established by the required date to allow for subsequent species translocations.
All three sites provide fantastic habitat on previously degraded areas of land, forming part of the wider HS2 green corridor.