The borough has sixty - seven Sites of Importance for Nature Conservation , eight Local Nature Reserves .
It is jointly responsible with the London Borough of Brent for the Welsh Harp ( Brent ) Reservoir , which is a Site of Special Scientific Interest .
The borough has sixty - seven Sites of Importance for Nature Conservation , eight Local Nature Reserves , and it is jointly responsible with the London Borough of Brent for the Welsh Harp ( Brent ) Reservoir , which is a Site of Special Scientific Interest .