GROUNDWATER MONITORING
REQUIREMENTS
Comment on the
differences between
monitoring for
surface and
groundwater.
Groundwater’s Status Quo
 Millions
of m3 pumped every year:
Monitored?
Who? How?
 100’s
of thousands of users:
Registered?
Controlled?
 10’s
of thousands of wells/boreholes:
Registered?
Maintained? Info. about location, abstraction levels, water levels,
water quality, formation, etc -
 1000’s
of sources of pollution:
Location,
nature & quantity of pollutants? aquifer vulnerability?
 Many
governing departments/institutions:
management ? Coordination / cooperation?
Joint
General Introduction
Groundwater is:
 an extensive, concealed and relatively
inaccessible resource.

INVISIBLE..!
One way to make groundwater visible...

by MONITORING it, e.g: Monitoring groundwater level shows a
declining water table – which allows water managers to obtain an
appreciation of the status of the resource.
Year-wise depletion of groundwater
One way to make grdwater visible...(contd.)
Some Consequences of GW abstraction
When pumping is
further increased
Excessive
pumping
Normal consequences
of
any groundwater
pumping
Groundwater Monitoring Systems by Function
SYSTEM
BASIC FUNCTION
Primary
(Reference)
Monitoring
evaluation of general groundwater behaviour,
e.g.:
 trends resulting from land-use change + climatic
variation
 processes such as recharge, flow and diffuse
contamination
Secondary
(Protection)
Monitoring
protection against potential impacts to:
 strategic groundwater resource
 well-fields/springheads for public WS
 urban infrastructure from land subsidence
 archaeological sites against rising WT
 groundwater-dependent ecosystems
early warning of groundwater impacts from:
• intensive agricultural land use
Tertiary
• industrial sites
(Pollution
containment) • solid waste landfills
Monitoring • land reclamation areas
• quarries and mines
WELL LOCATIONS
in areas with
uniform
hydrogeology
and land use.
around
facilities/areas/
features requiring
Protection.
immediately down
+
up-gradient from
hazard
Types of data for Groundwater Management
DATA TYPE
Groundwater
Occurrence &
Aquifer
Properties
BASELINE DATA (from archives)
Supporting
Information
field stations)
 grdwater level
logs, grdwater
monitoring
levels, quality, etc.
 grdwater quality
 well & aquifer pumping tests
monitoring
 hydrogeologic
 water
Groundwater
use
TIME-VARIANT DATA (from
well pump installations
 Water use inventories
 Population registers & forecasts
 Irrigation energy consumption



climatic data
land-use inventories
geologic maps/sections
water well abstraction
monitoring (direct/indirect)
 grdwater level
variations

 riverflow gauging
 meteorologic
observations
 satellite land-use
The Monitoring Cycle
Mgt question &
monitoring objectives,
e.g. trends & changes,
impacts & risks, etc.
of
needs
Mgt of info. & actions
Define actual info.
needed, what for,
wherefrom..? etc.
static & dynamic water
levels, water quality
When is groundwater monitoring considered
cost-effective?
 it
is driven by a specific objective – monitoring
for its own sake often leads to inefficient use of
manpower and budgets
 data collected is:
only used for the explicit purpose of the
monitoring programme, but
 Also systematically stored for future use – there are
far too many cases of monitoring data being lost
along the way.
 NOT
Effectiveness of groundwater monitoring
....is improved by careful attention to:
 network
design
 system implementation
 data interpretation
 data storage from past monitoring activities
 accessibility of monitoring stations...
 participatory monitoring amongst water users
 interpretation and use of data to formulate
management actions
Measuring GW Use & Aquifer Behaviour
Primary goal of aquifer management is to:
 develop groundwater resources on the basis of
a policy plan.
 monitor & control impacts of abstraction on
groundwater systems.
Thus, monitoring grdwater abstraction + aquifer
water levels provides key information for
management of grdwater resources.
Measuring GW Use & Aquifer Behaviour (contd.)
Monitoring of:
 grdwater abstraction, and
 aquifer water levels
combined with management actions – reduction
of pumping – can contribute to more stable
development of groundwater resources.
Example: Where historic data reveals over-abstraction..
Establishment of baseline situation:
Application of mgt actions, & monitor
Monitoring data
Is there any dedicated
Questions
monitoring network in
your country, or are
existing production
boreholes used?
Who is responsible
for data collection,
storage,
interpretation and
management?
Which
parameters are
monitored, and
why this choice?
Detecting Groundwater Quality changes
Grdwater monitoring requires special sampling
procedures as:
 well pumping
sample handling may cause major
sample modification through;
 air entry

+
degassing + volatile losses
NEED for appropriate sampling procedures.
Summary of sampling procedures and precautions for specific groups of
groundwater quality parameters
In designing a monitoring
network, what key steps
would you take in terms of
installation/selection of
monitoring wells; data
acquisition (who-by,
frequency, etc.); data storage
and interpretation
Early warning potential threats to Aquifer +
Groundwater supply quality
a
critical requirement for detecting any
threats to groundwater quality
Design of monitoring networks necessary,
which...

relates to the spatial variation of
grdwater flow + quality of more recent
recharge....
Early warning of potential threats to Aquifer +
Grdwater supply quality (contd.)
Detection of groundwater quality trends in aquifer replenishment
in vicinity of a public-supply water well
Early warning of potential threats to Aquifer
Grdwater supply quality (contd.)
+
Many cities have experienced rapid growth of urban &
industrial waste disposal to the ground....
Early warning of potential threats to Aquifer +
Grdwater supply quality (contd.)
.....thus, necessitating a focused groundwater quality
management monitoring, using sampling piezometers.
Early warning of potential threats to Aquifer +
Grdwater supply quality (contd.)
Some objectives of such sampling piezometers:
 to facilitate early warning of the onset of
groundwater pollution........ – to allow timely
introduction of necessary control measures.
 to provide advance warning of the arrival of
polluted water at an important groundwater supply
source and make provision for treatment or other
mitigation.
What important
natural or
anthropogenic water
quality problems are
in your country?
Who carries out
the monitoring?
Basic rules for a successful groundwater monitoring
programme - summary
 objectives
Network
Network
Design
Design
must be defined and program adapted accordingly

systemand
must
be understood
 groundwater
objectives must flow
be defined
program
adapted accordingly

locations
andmust
monitoring
parameters must be selected
 sampling
groundwater
flow system
be understood
to objectives
 according
sampling locations
and monitoring parameters must be selected by
objectives
appropriately-constructed
observation
+ abstraction
appropriately-constructed
observation
+ abstraction
wells mustwells
be
System
System
implementation
implementation
must be used
used
 field equipment + laboratory facilities must be appropriate to
 field equipment + laboratory facilities must be appropriate to the
the objectives
objectives
 a complete operational protocol + data handling system must
 a complete operational protocol + data handling system must be
be established
established
 groundwater + surface water monitoring should be integrated
 groundwater + surface water monitoring should be integrated where
where applicable
applicable
 data
DataData
interpretation
interpretation
quality
be regularly
checked through
through internal
internaland
and
quality must
must be
regularly checked
external
controls
external controls

makers
be with
provided
withmanagementinterpreted
 decision
decision makers
shouldshould
be provided
interpreted
management-relevant
datasets
relevant datasets

shouldbebeperiodically
periodically
evaluated
reviewed
 program
program should
evaluated
andand
reviewed
Thank you for your attention