Capitan Reef, A Brackish Water Resource

Capitan Reef, A BrackishWater ResourceDenise WannJuly 22, 2003

The Rhyme of the AncientMarinerby Samuel Taylor ColeridgeWater, water, everywhere,Nor any drop to drink.

Fresh Water Facts• By volume, only 3% of all water on Earth isfreshwater and most is unavailable, locked up in theform of ice caps and glaciers far from humans.(Iyioke,, 10/1998)• Only 1% is easily accessible surface freshwater.(Iyioke,, 10/1998)• “Fresh water supplies are shrinking so fast that asmany as 7 billion people in 60 countries could facewater scarcity by 2050.” (The Washington Post,March 2003)

Fresh Water Facts• “Water promises to be to the 21 st centurywhat oil was to the 20 th century: the preciouscommodity that determines the wealth ofnations.” (Fortune Magazine, 5/2000)• “Most North Americans think watershortages are just a third world problem. “(Barlow & Clarke, 2002)

Brackish Water Facts• Saline and Brackish waters account for about97% of the waters in the world.• Brackish water is defined as salinity from3,000 – 10,000 mg/L TDS (Total DissolvedSolids)– Humans prefer to drink 10,000 mg/LTDS.

An Ocean of Water• ~12 million BWPD is produced and reinjectedin the Permian Basin. (Morales & Barrufet)• If the brackish water produced in Lea Countyper year could be purified, it could sustain acity of 300,000. (July 2003)• Consider the possibilities!

Capitan Reef Formation(A Reef in the Desert –(Pima 2003)• The reef began to form along theborders of the Delaware Sea ~250million years ago.

Capitan Reef Formation(A Reef in the Desert –(Pima 2003)• The reef thrived for millions of years.Growth ended near the end of the Permianperiod.• At the end of the Permian Period, animals andplants began to die. (the great extinctiontime)• The Delaware Sea’s link to the ocean closedoff, most likely due to either dropping sealevel or a rising continent.

Capitan Reef Formation conti(A Reef in the Desert –(Pima 2003)conti.• As this happened, minerals startedprecipitating out of the water, falling to theseafloor. Thin layers of sediments filled thebasin and covered the reef layer by layer.

Capitan Reef Formation conti(A Reef in the Desert –(Pima 2003)conti.• The Capitan Reef remained buried until majorfaulting began ~26 million years ago. Faultinglifted the present day Guadalupe Mountainsup, nearly two miles.• After the reef was uplifted by the faults, thewind and rain wore away the sediments on theexposed reef leaving the more resistantrocks.

Capitan Reef Formation conti(A Reef in the Desert –(Pima 2003)conti.• During the time of tectonic activity, therewas widespread fresh water influx throughthe Permian sediments, in particular theCapitan Reef.• The closer to the mountain ranges, thefresher the water.

Capitan Reef Today• Parallels the western and eastern edges ofthe Delaware Basin in two strips 5-145mileswide.

Capitan Reef Today• Depths range from shallow to ~ 4000’• Reef is exposed at the surface in theGuadalupe, Apache and Glass Mountains(shown in red)

Capitan Reef Today• TDS averages from ~1000 – 3000 mg/L,considered slightly to moderately saline.(LBG-Guyton Guyton Associates)– Used as fresh water resource for Carlsbad– Used for irrigation in Guadalupe Mountains– Used for livestock in Apache and Glass Mountains– Used for Waterflood Operations in New Mexicoand Texas

Capitan Reef Today• Has the potential to produce large quantitiesof groundwater and should be considered agood potential brackish groundwater resource(LBG-Guyton Guyton Associates, 2003)

Where Do We Go From Here?• Desalination pilot test in the Capitan Reef– Would yield the most cost effective andtechnologically feasible purification process

Denise Wann 2003For such a time as thisan ancient Sea was laidBuried but not forgottento come alive somedayIn our weakness, is our strengthfor bound together we must beA daunting task ahead of usto awaken this mystical SeaThe challenge is great, the task immensethe winner not yet knownWill fear strike us before we startor will a victory be sownNothing ventured, nothing gaineda famous saying we all knowBelieve and live it everydayand greatness will be shown