Dros y blynyddoedd, oherwydd eu lleoliad, mae datblygiadau adeiladu a seilwaith wedi bygwth llyncu tir Lefelau Gwent ac mae llygredd aer, dŵr a phridd ynghyd â lledaeniad prysgwydd ar hyd llawer o’r ffosydd wedi bod yn erydu’u gwerth.
Over the years the location of the Gwent Levels has also made them vulnerable to encroachment by built development and infrastructure, whilst pollution of air, water and soils coupled with scrub invasion along many of its reens has been eroding away this unique interest.