Loch Garman's mythological origin is also given in the dindsenchas – in some translations or interpretations of the text the source of the water is given as the Well of Coelrind, though this has also been rendered as port of .., or even fountain of ...
In the poem the well is associated with the drowning of Sinend, daughter of Lodan Lucharglan, son of Ler, of the Tuatha Dé Danann – giving the river its name.
[1] Tipra Chonnlai, ba mór muirn, bói fon aibeis eochar-guirm: sé srotha, nárb inann blad, eisti, Sinann in sechtmad.
Nói cuill Chrimaill, ind fhir glic, dochuiret tall fon tiprait: atát le doilbi smachta fo cheó doirchi dráidechta.
The nine hazels of Crimall the sage drop their fruits yonder under the well: they stand by the power of magic spells under a darksome mist of wizardry.
[6] Nechtain mac Labrada laind, diarbo ben Bóand, bágaimm, topur diamair bói 'na dún, assa maided cech mí-rún.
Nechtain son of bold Labraid whose wife was Boand, I aver; a secret well there was in his stead, from which gushed forth every kind of mysterious evil.