Why Test the Aquifers of Why Test the Aquifers of New Mexico?New Mexico?

Why Test the Aquifers of Why Test the Aquifers of New Mexico?New Mexico?

W. Peter Balleau,W. Peter Balleau,Balleau Groundwater, IncBalleau Groundwater, Inc.

January 24, 2009January 24, 2009

CHALLENGES TO GROUNDWATER RESOURCE DEVELOPMENT

•“The sustainability of groundwater represents one of the major water challenges.”

-3rd World Water Forum (2003)

•“The problem of ground water mining represents a fundamental threat…”-World Bank (1999)

•“The country cannot sustain even the current levels of groundwater use…we must act to protect our rivers, springs, wetlands, lakes and estuaries from groundwater pumping.”

-Water Follies (R. Glennon, 2002)

•“Water in the West: …the American West is facing a serious water crisis. In the long run, we do not have enough water to meet the West’s fast-growing needs.”

Barackobama.com (2008)

DRY SEASONBASEFLOW FROM

AQUIFER DISCHARGE

SUM = 300,000 AFYAQUIFER YIELD

Wells

DRY SEASONBASEFLOW FROM

AQUIFER DISCHARGE

SUM = 300,000 AFYAQUIFER YIELD

Wells

NEW MEXICO AQUIFER DISCHARGEBasin Dry Season Baseflow

(AFY)Well Withdrawal1

(AFY)

Canadian River 6,000 66,000

Rio Grande 80,000 695,000

Pecos River 60,000 445,000

Mimbres River 2,000

San Juan River 6,000 4,000

Gila/San Francisco River

45,000 104,000

High Plains 100,000 525,000

300,000 AFY(some already

depleted by wells)

1,800,000 AFY

1New Mexico Office of the State Engineer, 2008

SANTA FE

ESTANCIA

REGIONAL TREND EXAMPLE

AREAS OF AQUIFER DRAWDOWN

Adapted from: USGS, 1972, New Mexico State Water Plan:Map Showing Observed Changes of Ground-Water Level and Hydrographs of Selected Wells in New Mexico.

Wells

AREAS OF WELL DENSITY

OBSERVED BASEFLOW GAIN ON SEGMENT OF PECOS RIVER, NEW MEXICO

0

20,000

40,000

60,000

80,000

100,000

120,000

140,000

Jan-1900 Dec-1909 Jan-1920 Dec-1929 Jan-1940 Dec-1949 Jan-1960 Dec-1969 Jan-1980 Dec-1989 Jan-2000

DATE

BA

SE

FL

OW

(A

FY

)

OBSERVED BASEFLOW GAIN ACME TO ARTESIA

TREND OF BASIN DRYING OUT

ECOLOGICAL WATERS

>5700 Miles of Perennial Streams

> 4600 Springs

An Estimated 100,000 to

200,000 AFY Riparian Loss

(on top of baseflow 300,000 AFY)

THE GROUNDWATER IMPACT PROBLEM

+ new water (temporary)

How much to be reserved for ecological waters and downstream obligations, or taken for economic use?

SUSTAINABLE GROUNDWATER•Creates a managed, desirable groundwater condition regarding levels and chemistry.

•The “available groundwater resource” is the amount that also achieves ecological objectives and meets downstream obligations.

•Administering surface water rights does not result in sustainable groundwater development, (CU>net effect).

•The benefits of groundwater storage development need not be abandoned in the name of “sustainability”.

WHY AQUIFER/PUMP TEST?•Pick pump size and setting•Decide cause of well problem: Aquifer?

Screen?Pump?

•Subdivision approval on water availability•Find effects on neighbors for permitting•Find effects on own wellfield for management•Aquifer characterization for system management or models

Aquifer Properties

Storage CoefficientIs Volume of Water

Per Volume of Aquifer Drawdown

(ranges 1 AF water per 10 to 100,000 AF cone volume)

TransmissivityIs the flow in

a 1-ft wide stripof aquifer

(ranges 1000gpd to 100,000gpd per 1-ft strip, then adjusted for gradient)

33%

66%

100%

133%

166%

0

2

4

6

8

10

12

14

16

1 Minute 15 Minutes 2.4 Hours 1 Day 10 Days 100 Days

BENEFIT OF SHORT AND LONG TESTS

1-Day TestPeriod

(Plus information from recovery period)

Dra

wdow

n D

ata

KINDS OF WELL TEST

•Well-development pump•Step-test, multi-rate•Short-term, 1-12 hours constant rate•Longer-term, 1-10 days, rarely longer•Observation wells•Extended recovery•Operational tests-more popular

STEP TEST

s = bQ + cQn (Jacob, 1947) - Not a Management Tool

SUBDIVISION DOMESTIC WELL TEST

1. Drill and install a properly-constructed domestic well on the subdivision site.

2. Pump the well under controlled conditions at a rate of 5 to 20 gpm for 24 hours (or longer per County).

3. Collect water-level recovery data for three days after the end of pumping.

4. Calculate the radius of influence of the test and check if additional wells and tests are needed to get a representative sample of the subdivided area.

Adapted From:USEPA, 1993, Groundwater Issue: Suggested Operating Procedures forAquifer Pumping Tests, EPA/540/S-93/503.

Not quite full recovery

Not quite stable drawdown

Pump test methods have not changed much

Frequency Test Duration

1 min. 20 min.

5 min. 25 min. to 1 hr.

10 min. 1 hr. to 2 hrs.

30 min. 2.5 hrs. to 6 hrs.

1 hr. 6 hrs. to 12 hrs.

2 hrs. 14 hrs. to 24 hrs.

6 hrs. 1 day to 2 days

Daily 2 days or more

(Appreciable variation can be accepted)

OPTIMUM TIMES OF WATER LEVEL MEASUREMENTS FOR WELL AND AQUIFER TEST DATA

Wier Box

M-SCOPE

MeasuringTube

DRILLER TEST SETUP

•Rate control valve and meter•Electric probe, steel-tape and chalk, or transducer•Measuring tube•Pretest data•Recovery data twice as long as pump•Water-sample kit from lab

OPERATIONAL TESTING

Install: •Meter, recording•Measuring tube (Required by Regulation)•Transducer (pumping water level), recording

EXAMPLE 15 MINUTE DATA

6620

6625

6630

6635

6640

6645

6650

6-Apr 13-Apr 20-Apr 27-Apr 4-May 11-May 18-May 25-May 1-Jun 8-Jun

DATE

GR

OU

ND

WA

TE

R E

LE

VA

TIO

N (

FE

ET

, NG

VD

29)

5 9 5 0

5 9 6 0

5 9 7 0

5 9 8 0

5 9 9 0

6 0 0 0

6 0 1 0

5 9 5 0

5 9 6 0

5 9 7 0

5 9 8 0

5 9 9 0

6 0 0 0

6 0 1 0

5 9 5 0

5 9 6 0

5 9 7 0

5 9 8 0

5 9 9 0

6 0 0 0

6 0 1 0

5 9 5 0

5 9 6 0

5 9 7 0

5 9 8 0

5 9 9 0

6 0 0 0

6 0 1 0

PWL

Pump Setting No Change = No Problem

SUSTAINABLE

REGIONAL TREND

Change in PWL = Well

LOSE EFFICIENCY

DEWATER SCREEN, FRACTURE OR PWBS

Change in SWL = Aquifer

Abrupt Change

SWL

MANAGEMENT BY TREND ANALYSIS

Well Tests by Drillers are Needed

• To ensure well performance for the owner/user• Permitting• Data to help Manage and Operate aquifer,

wetland, and surface water systems to maintain hydrologic conditions for ecological waters, downstream obligations, and economic use.

“Water is fundamental for life and health. The human right to water is indispensable for leading a healthy life in human dignity. It is a prerequisite to the realization of all other human rights”.

(U.N. Committee on Economic Cultural and Social Rights)