Blackwater is the fifth studio album by County Donegal, Ireland, traditional music group Altan, released on 5 April 1996 through Virgin Records.

Featuring an eclectic mix of Irish and Scottish jigs, reels, and hornpipes, along with a strathspey and barndance (both unique to County Donegal), Blackwater was Altan's first record to be produced and released following the tragic death of flautist and founding Altan member Frankie Kennedy in 1994; Kennedy was married to frontwoman Mairéad Ní Mhaonaigh.

The track's arrangement gradually builds in intensity, with Ní Mhaonaigh's solo fiddle playing the first round before being joined by the rest of the band.

The album features "no-frills", clear arrangements of music and song; the intricately-woven double fiddles of Ni Mhaonaigh and Ciarán Tourish and the button accordion mastery of Dermot Byrne are expertly backed by Ciarán Curran on bouzouki and Dáithí Sproule and Mark Kelly on guitars.

"Blackwaterside", a song about falling in love with someone who is not interested, is sung in English and features a string section with the acclaimed Yo-Yo Ma on cello.