The main trace for Silver Birch Way is https://www.openstreetmap.org/user/hadw/traces/11375002

The upwards loop at the left side is the new road up to the University entrance gate, then along a short existing cycle path, and back along Watford Road, to th start of Silver Birch Way.  The downward loop is the front of the maternity building,  but that is identifiable in existing imagery.