Yn dilyn y glaw eithriadol o drwm a ddisgynnodd ar 8 a 9 Mehefin 2012, a symud trigolion pentref Pennal ar 10 Mehefin 2012, defnyddiodd Asiantaeth yr Amgylchedd ei phwerau o dan Ddeddf 1975 i benodi Peiriannydd Panel Pob Cronfa Ddŵr i gynnal ymchwiliad peirianyddol i’r digwyddiad.
Following the extreme rainfall event on the 8 and 9 June 2012, and the subsequent evacuation of Pennal on 10 June 2012, the Environment Agency used their powers under the 1975 Act to appoint an All Reservoirs Panel Engineer to carry out a post-incident engineering investigation of the reservoir above the village.