2113f2015**Prl~malll** Science Feerures 

# EUSGS
science for s changing world 

# The Quality of the Nation's Groundwater

Thill Sciem:e Feature ambe fOUDd at: hUp:llwww.usgs.gov/blogs/fcatURS!usgB top stmyfthc..quality-of-1he-nations-groundwatcr/ Categories: 

### Featured. Wl1lm:

- - POIItcd on Jamwy 

### 21, 2015 at 

### 10:46 am By: Barbara Mahler, 

### Jon CampbeD About 115 million peopl.o--mo.rc 1han**~1hird** 

### oflheNation's population-rely on groundwater fur drinkiDg 

### water. As the 

### Nation's population grows, 1he need fur high-quality drinking-water 

### supplies becomes even mon: urgent.



### Ground water

--The Invis ibl e and V ital Resour ce 11 S Million People tefy ongroundwat@r for dnnklngwat« 43 Million Pooplo rf!ly on groundwater Irom**p~tv.lle** Wl!lh 1 of ev e ry S Groundwa ter**sampl~s** from ptrb ofaqulf«JuWid br li1 nk1ng wilt« (Ont.lnld .a conumlnant from gcologk: orm.11nmade SOUlOIS**o~t a~**  e-xcMd1ng a potential human-Malth concern 6,600Wells**~~~edfotthl$$fudy** 1 .1 Million C hemical Analyses porfonnod '"'**th~** ltucly
Oroundwatl=r -The Jnviaiblc andVibll Rcso1m:c. Details: 

### liS million people 

### rely on 

### groundwater fur 

## drinldDs water. 43 million people 

### rely on groundwater from private wells. 

### 1 of



### every 5 grouDdwater 

### samples from parts ofaquifers used fur drinking watcr c:outaincd a c:ontaminant from pologic; or 

### m1111made 

### sources at

### a level exceeding 

### a potential 

### humanhealth c:mu:em. 

### 6,600 wells were 

### sampled fur 1hia study. 

### 1.3 million 

### c:hemical analyses performed for this study. 

## _]

hUp:llwww.usgs4Pflblogs/falmeslpriramailf1post=208531 "Through the WaterSMAR.T initiative andthe 

### Nlllional Water-Quality Aaaeasment 

### Program, the Depimment 

### of

### Interior is working to BOCUI'O 

### sustainable water supplies 

### ofsufficient 

### quantity 

### and quality and to 

### identifY measures needed to address cl.imatll clumge and future demands," llldd Jeunifer Gimbel, 

### Principal Deputy 

### Assistant Sea'etary 

### of 

### the U.S. Department of 

### the IDterior. "The integrall:d work that USGS is cloing to 

### map groundwater availability, groundwater quality, and 

### 1he potential 

### for contamination will give us the 

### information 

### we need to UDdmtarul 

### natural and human effecta 

### on groundwater 

### and to take the action8 needed to protect this vital natural MSourec." 

### The :recently 

### completed 

### national •mmmmy 

### rePOrt of 

### the quality 

### of the 

### Nation's groundwater 

### is now available online. Nine associated report& (USGS circ:ulan) detail tegional-ICale aue&III!lel1t& 

### ofgroundwater quality in 

### about 30 

### of the 

### most heavily used principal aquifers 

### across the United Sbdl:a. 

# A deep look at an unseen resource
Over 

### the last two decades, USGS scientist& have uaessed water quality in IIOURle (untreated) water from 6,600 wells iD extensive regional aquifers 1lurt supply most of the groundwater pmnped for 

### the Nation's drinking water, irrigation. and other uses. 

### This comprehensive aampliDg,**alm~g** with detailed infom!ation on geology, hydrology, geoc;hcmistry, and c:hcmic:al andwater

## use. ambe usedto 

### explain how and why aquifer vulnerability to 

### contamination varies 

### across the 

### Nation.



### 113

### 2/1312015**Prl~alll** Science 

### F-*'• 

### Excee d a n ces of human
- health be n chma rks by one or more contam i na n ts

Columbi a P lateau basin-fill Columbi a P l ateau basalt
Willamette

Basin and Range carbonate

Central Valley

Basin



# -

. Basin and Range basin-fill



# 0\**Hawaii ~**  volcanic Snake River Plain basal t

lowl ands CambrianO rdov i ci an

EXP L ANATION Perce n tage of wells with o n e or more co n ta m inant

at a concen tration g reater t h an a huma n - h ea l th benchmark 

# 0 None 

# D From geo l ogic so u rces 

# D From human sources New Eng l and crystalline

All aqu ifers

# So/o 

# \:::_)

Wustmtion: Map 

### llhowiDg many 

### c:barts indicating "BxceedaDce& 

### ofhuman-beallh beoohmarb by 

### oDe or**mcm~** 

### contanrinauts"- For m1m1 chaila 

### on exaa 

### numbers, pleuo ndK to the liDbd MIOIIIIXlll 

### inthis lltOJy. 

# National Findings

• More tlwl 

### one in 

### five (22**pe~CC!~t)** grol&lldwater 

### samp!ea contained ItlCMt 

### one coniiiiDiaaDt 

### at a ccmcelltration 

### oi poCelltW 

### coace:m for 

### humaa. health. 

### • Contamm•nt;a from 

### geologic IIOUICCt--primarily m"''gg""*, 

### anemic. alld**~for** about 

### 80 

### P=Qrt of

### C(tllfamjnant COIICCI!tratiOJU**that~**



### a humall-health bencbmazk. 

### N"ltrate, 'Which exceeded i1lll 1.-eadun•rlr in 

### about 4 perce1rt ofwdls 

### sampled, 

### wu the Ollly coJUtituelrt from 

### mnnwle 80al\lC8 

### dlat exceeded it8 

### humall-bulth beuchmark in 

### mcm: 

### thn 1 pm:eat 

### of

### samplee. • DitfereDee8 in 

### COiltaminmt COllCC!IIra1iou 

## amona aquifers, within 1111 

### aquifer, 

### arul even between two neatby 

### weDs can 

### be explaillecl by 

### large- 

### arullocal-ecale

clifferalces in

### geology, hyclrology, geochemietry, 

### 8lld chemical 

### 8!14 water UBC. 

### Ullderatlllding how 

### D8IU!a1 featDre8 

### end human activities atfect 

### poUildwater quality helpt 

### 1D predict 

### how 

### end why aquiferw!Derability 

### to contamillation 

### variee aaou 

### the Nldiou. 

## • Hiah-volame pumpina 

### ad ilription in

### many areas have 

### profoadly dlanged. 

## JfOUIIClwata" flow end quality. 

### By 1DOVing 

### shallow gt'OIIIIdwater deepet-, into

parts 

### ofaquifers mecl for 

### drinkillg 

### wamr, iniption 8lld pumping have incrasecl the 

### vuJnmoabilily of

### drinking-wamr supplies to 

### contamination ftom l1ilrate, paticides, 8.lld 

### other manmade cbemU:als fmm the land ll1lrlilce. • lnigation, 

### hish-volume pumpillg, 8lld artificial 

### mc:harge can cause cliffienttype& 

### ofwatms to 

### mix, 

### wilh the 

### unexpecll!d ccmseqwmce of

### causing the 

### aquifer

rocks 

### 8lld sediment to

### relealeutumlly 

## 11CC11IJiD.s contaminants, sw:h 

### as lllllllllic, aelaoium, or

### Jadinm. into tba groundwm£. 

### Conccm1nJtions ofclissolveclsolidl, chloride, 8.lld Di1IatD, 

### iDdic:atonl ofhuman iD1Iwmce 

### on grol&lldwater qualily, 

### i.ncmasecl from the 

### 1990.to 

### 2010 in llhallow 

### grollllllwiMr inmany parts 

### ofthe 

### Nalicm. Similar chatJges 

### are likely to 

### occur in deeps- 

### puts ofIOIJiellll.uifm-1 

### in the future 

### as the shallow water 

### moves clownwmt. 

### Omundwatm- in

### ptmlllllble, unc:cmfiJied aquifin, sudl U tbll 

### CenDBl Vlllley aquifer 

### system in California, is especially 

### vulnmable 

### to c:cmtamination

### 2/1312015 PrintEmaill 

### Science F811bns 

# Regional Principal Aquifer Assessments Jn..depth,**regiooal~o** 

### asMSsmenb 

### ofgrollll(lwater 

### quality fuws 

### on abou130 of

the !DOlt heavily U&ecl 

### PriDcipal 

### Aquifers inthe 

### Nation. Groundwater 

### quality in 1hae 

### aquifcn----end the factors that affect 

### it-is described in Dine 

### new U.S. Geological Survey**cimllm~.** 

### Glacial**Aq~~ifer** 

### System (northem 

### U.S.) 

### Wemmvntmriq (Dmthwestem 

### U.S., Hawaii) 

### Sou1hwest Basin-

### :till Aqyifm (sou1hwestem 

### U.S.) Dexwer Buin

### Aquifer System (Colorado) PjedmOJ!t. Blue Rjclje. and

### Valley and 

### Ri!JB Aquifcxs (eastem 

### U.S.) Nor!hem Atlantic CrueT!!) Plain Surficial 

### Aqy.ifer Sytrtem (east cout 

### ofU.S.) 

### UJmer Floridan 

### AQuifer 

### and ()yer]yiD& 

### Swficial AgJ!ifq (southeutem

### U.S.) OudiDes 

### ofpriDcipal aquifml 

### of the U.S. 

### For detail• 

### on the 

### map, pleue

### use the 

### liDkedn:sources available in 

### this story.
Mississi&mi 

### Jo:mbayment- 

## Texas Coastal Uplpd Aquifer System and 

### Mississ!&mi 

### Riv« Valley A1luyial 

### Aqyifer (SOU1heastem, southcentral 

### U.S.) Hip plajpa 

### Aquifer Sy&Wn 

### (cen1ral U.S.) 

# Looking forward
Over 

### 1ho next 

### decade, about 2,300 sballow wells 

### and 1,400 deep public-supply 

### wells will bo sampled for 

### a 

### broad rango ofwater-quality coutitueDts 

### as the 

### National Water-Quality 

### Auei8Dle:nt Plogrun 

### continue• to 

### add!eu the three 

### CCDtral 

### queationa: 1. What is 

### 1ho quality of1he Nation's 

### groundwater, 2. Ia 

### it ptt:iDg better or WOllle, aad 

### 3. What factors affect 

### 1he quality of1his vital

### resource. In

### the future, 

### USGS-led natiooal 

### and regioual scale mocleliDg willprovide 

### a 1hreo-dimeuioual pcrapective of1hc quality 

### of the 

### Nation's grouadwater tbat 

### can be U&ecl to inform 

### management clcci&ona. 

# Learn more USGS 

### National Snmmm Cjrcular. Quality q.ffire Nqtimz 

### 's Growufwqtu Quality. 1991-2010 

### R.eLtional re,pom (JUne) 

### on

### principal aqgifm gfd!e 

## u.s. NatiQ11al 

### Wltet-Qwili\y 

### Asseasmmt (NAWQA) 

## Pmamm USGS GroundWl!ter Infurmation 

### WaterSMART

313