FprEN 18049-1

SLOVENSKI STANDARD
oSIST prEN 18049-1:2024
01-marec-2024
Vodnjaki za črpanje vode - 1. del: Načrtovanje
Wells for water extraction - Part 1: Design
Brunnen zur Wassergewinnung - Teil 1: Design
Forages pour l'extraction de l'eau - Partie 1 : Conception
Ta slovenski standard je istoveten z: prEN 18049-1
ICS:
93.025 Zunanji sistemi za prevajanje External water conveyance
vode systems
oSIST prEN 18049-1:2024 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN 18049-1:2024
oSIST prEN 18049-1:2024
DRAFT
EUROPEAN STANDARD
prEN 18049-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2024
ICS
English Version
Wells for water extraction - Part 1 Design
Puits pour l'extraction de l'eau - Partie 1 : design Brunnen zur Wassergewinnung - Teil 1 Design
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 451.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 18049-1:2024 E
worldwide for CEN national Members.

oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
Contents Page
European foreword . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Project objectives .15
4.1 Background .15
4.2 Requirement .15
4.3 Compliance .15
5 Site conditions .16
5.1 Background .16
5.2 Requirements .16
5.3 Compliance .16
6 Geological and hydrogeological characterization .17
6.1 Background .17
6.2 Requirements .17
6.3 Compliance .18
7 Qualitative risk assessment .19
7.1 Background .19
7.2 Requirements .19
7.3 Compliance .19
8 Estimation of yield .20
8.1 Background .20
8.2 Requirement 1.21
8.3 Compliance .21
8.4 Requirement 2.21
8.5 Compliance .21
9 Pump selection .22
9.1 Background .22
9.2 Requirement .22
9.3 Compliance .22
10 Dimensioning of the well .23
10.1 General background .23
10.2 Casing .26
10.3 Annular space .26
10.4 Formation stabilizer .27
10.5 Filter pack (gravel pack) .27
10.6 Annular seal .29
10.7 Clay plug and separation filter .30
10.8 Open area coefficient .30
10.9 Critical entrance velocity .31
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
10.10 Length of screen section . 32
10.11 Sump . 32
11 Selection of materials . 33
11.1 General . 33
11.2 General requirements . 33
11.3 Filter pack. 33
11.4 Casing and screen . 35
11.5 Sealing . 37
11.6 Backfilling. 38
12 Additional well equipment . 39
12.1 Background . 39
12.2 Requirement 1 . 39
12.3 Compliance . 39
13 Observation wells . 41
13.1 Background . 41
13.2 Requirement 1 . 41
13.3 Compliance . 41
13.4 Requirement 2 . 42
13.5 Compliance . 42
13.6 Requirement 3 . 43
13.7 Compliance . 43
14 Drilling methods . 43
14.1 Background . 43
14.2 Requirement 1 . 43
14.3 Compliance . 44
14.4 Compliance . 44
15 Drilling fluids . 44
15.1 Background . 44
15.2 Requirements . 44
15.3 Compliance . 45
16 Geophysical well logging . 46
16.1 Background . 46
16.2 Well logging methods . 46
16.3 Quality assurance for the performance of well logging measurements . 47
16.4 Design of logging programmes . 47
17 Development . 49
17.1 Background . 49
17.2 Requirement 1 . 49
17.3 Requirement 2 . 50
17.4 Compliance . 50
17.5 Requirement 3 . 51
17.6 Compliance . 52
17.7 Requirement 4 . 52
17.8 Compliance . 52
17.9 Equipment . 53
17.10 Specific requirements . 53
18 Pumping test . 53
18.1 Background . 53
18.2 Minimum equipment for the well to be tested . 54
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
18.3 Location of observations .54
18.4 Pumping system .55
18.5 Monitoring equipment .56
18.6 Performing a pumping test .56
18.7 Water sampling and analyses .57
19 Site waste management .58
19.1 Background .58
19.2 Requirement 1.58
19.3 Compliance .58
19.4 Requirement 2.58
19.5 Compliance .58
19.6 Requirement 3.59
19.7 Compliance .59
20 Control, maintenance and monitoring .59
20.1 Background .59
20.2 Requirement 1.59
20.3 Compliance .59
20.4 Requirement 2.60
20.5 Compliance .60
21 Evaluation of the design .61
21.1 Background .61
21.2 Requirement .61
21.3 Means to verify .61
22 Project design documents .62
22.1 Background .62
22.2 Requirement 1.62
22.3 Compliance .62
22.4 Requirement 2.62
22.5 Compliance .62
22.6 Requirement 3.62
22.7 Compliance .62
Annex A (informative) Examples of specific requirements depending on the purpose of the
well .63
Annex B (informative)  Failure mechanisms and impacts on the surrounding environment
....................................................................................................................................................................64
Annex C (informative) Submersible pump overall dimensions .73
Annex D (informative) Criteria for selection of the drilling method and specification of
drilling methods .74
D.1 Purpose of well .74
D.1.1 Exploratory well .74
D.1.2 Drinking water well: .74
D.2 Kind of rock .74
D.2.1 Consolidated rock .74
D.2.2 Unconsolidated rock .74
D.3 Planned depth .75
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
D.4 Necessity to collect reliable rock samples . 75
D.5 specification of the drilling methods . 75
D.5.1 General . 75
D.5.2 Auger method . 75
D.5.3 Cable tool method . 75
D.5.4 Down-the-hole hammer (DTH) method . 76
D.5.5 Rotary drilling method . 77
Annex E (informative) Terms, symbols, units and abbreviations of major logging techniques
................................................................................................................................................................... 81
E.1 Terms, symbols, units and abbreviations of major logging methods . 81
E.2 Logging programmes for open, temporarily cased/partially cased boreholes in
consolidated rock – Recommended logging programmes . 83
E.3 Logging programmes for open, temporarily cased/partially cased boreholes in
consolidated rock – Recommended logging programmes . 84
Bibliography . 86

oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
European foreword
This document (prEN 18049-1:2024) has been prepared by Technical Committee CEN/TC 451 “Water
wells and borehole heat exchangers”, the secretariat of which is held by AFNOR.
This document is currently submitted to the CEN Enquiry.
Within its program of work, Technical Committee CEN/TC 451 requested CEN/TC 451/WG 1 “water
wells” to prepare the following standard:
EN 18049-1, Wells for water extraction — Part 1: design.
The EN 18049 series under the main title Wells for water extraction will consist of the following parts:
— Part 1: design;
— Part 2: XXX;
— Part 3: XXX;
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
1 Scope
This document covers all types of water wells, whether for public or private use, abstracting from or
injecting water to the groundwater, in a variety of applications. These include potable water abstraction,
industrial use, irrigation, dewatering, infiltration or recharge, and geothermal applications, or for
groundwater observation (see Clause 13).
This document does not apply to horizontal wells and closed loop geothermal systems.
The document defines design requirements of water wells for public and private users in accordance with
groundwater protection goals. It gives guidelines for all planning steps from preliminary to final
executive project design.
A sequential method for designing and dimensioning a well is specified. Based on the hydrogeological
conditions and the objectives of the well, a step-by-step process for dimensioning the well is defined. This
methodology includes dimensioning for the drilling, filter packs, sealing and a screen. Furthermore,
selection of appropriate materials, the pump and all other additional well equipment is outlined. With
regard to the planning process references are provided for drilling methods, geophysical well logging,
well development and pumping tests.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN 14396, Fixed ladders for manholes
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
3.1
abandoned well
also called decommissioned a term used when a well’s use is permanently discontinued or if it is in a
condition that makes it uneconomic to repair
3.2
alignment of the well
measure of the straightness of adjacent sections of a well
Note 1 to entry: Often tested by running a dummy tool into the well.
3.3
annular space (annulus)
space between a drilled hole and the well casing
3.4
aquifer
water-bearing geological layer comprising permeable rock, fractures or unconsolidated materials
(gravel, sand, or silt)
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
3.5
aquifer stimulation
type of development that is carried out to alter the formation physically to improve its hydraulic
properties
3.6
aquifer test
special case of a pumping test using additional observation wells to obtain information about the
characteristics of a aquifer
3.7
aquitard
geologic formation having very low permeability
3.8
artesian aquifer
confined aquifer in which the piezometric surface is above the ground level
3.9
artesian well
wells (bore holes) that penetrate artesian aquifers
3.10
auger
machine having a rotating helical shaft for boring into the earth
3.11
bailer
cylindrical, bucket-like device with a footvalve used to collect or remove mud and rock cuttings from, the
borehole
3.12
borehole
hole created by drilling into the ground
3.13
bottom hole assembly
lower portion of the drill string, which may consist of (from the bottom up) the bit, bit sub, a mud motor
(in certain cases), stabilizers, drill collars, heavyweight drill pipe, jarring devices (jar) and crossovers for
various thread forms
3.14
cable tool
group of machines for drilling by the breaking and crushing action of heavy drilling tools suspended on a
cable which are repeatedly lifted and dropped
3.15
casing
tube (usually steel or plastic) that is installed in a well to maintain the well opening and to provide a seal
3.16
cementing
specific case of grouting where only cement and water are used
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
3.17
centralisers
devices used to ensure that casing or riser tubes are installed centrally within the borehole
3.18
confined aquifer
aquifer whose upper and lower boundaries are low permeability layers which confine the groundwater
under greater than atmospheric pressure
3.19
unconfined aquifer
aquifer with an upper surface as a water table, whose piezometric surface is at atmospheric pressure (an
unconfined surface)
Note 1 to entry: The level of this groundwater can fluctuate, creating a saturated zone and an unsaturated zone
3.20
core
continuous cylinder of rock, cut from the bottom of a borehole as a sample of an underground formation
3.21
cuttings
small pieces of rock or broken material derived from the drilling process, which can be used for sampling
3.22
Down-the-hole hammer
DTH
self-rotating air-activated percussive drilling bit
3.23
drawdown
decrease in ground water level caused by pumping, measured as the difference between the static and
the dynamic water level at a particular time
3.24
drill bit
cutting tool used in well drilling
3.25
drilling additives
specific components of the drilling fluid that can be used to restore the drilling mud properties or to act
in a particular way as required
3.26
drill collar
component of a drill string that provides weight on the bit for drilling
3.27
drill pipe
steel pipe used to carry and rotate the drilling tools in a well, and to permit the circulation of drilling fluid
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
3.28
drilling fluid
drilling mud
water or air-based fluid used in the water well drilling operation to remove cuttings from the hole, to
clean and cool the bit, to reduce friction between the drill string and the sides of the hole, and to seal the
borehole
3.29
dynamic water level
cf. static water level
piezometric surface influenced by drawdown or injection, as opposed to the natural water level at rest at
the same point;
Note 1 to entry: More specifically, drawn down or raised water level, whether or not stabilized, in a pumping well
or injection structure
Note 2 to entry: Static level (natural groundwater level): the piezometric surface in a borehole not influenced by
pumping, sampling or by injection of water
3.30
filter cake
suspended solids that are deposited on a porous medium during the process of filtration
3.31
free flowing well
(see artesian well)
3.32
formation
general term for the geological units surrounding the borehole
3.33
formation stabiliser
sand or gravel placed in the annulus of the well between the borehole wall and the well screen to provide
temporary or long-term support for the borehole
3.34
geophysical well logging
generic name for a suite of technologies that indicate absolute or relative properties of geological
formations, aquifers and wells
3.35
filter pack
gravel pack
coarse sand, fine gravel, glass beads, or other suitable materials, that is placed between the borehole wall
and screen
Note 1 to entry: Filter packs are used to retain the formation and improve the hydraulic condition around the
well.
3.36
grout
cement- and/or clay-based sealing material (e.g. swelling clay) used to create a sanitary seal in the
annular space to prevent crossflow between aquifers and/or contaminants from entering the well
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
3.37
head
for the purpose of this standard means hydraulic head
3.38
head loss
energy which is lost due to friction as water moves from an aquifer through the well (filter pack, screen,
pump, riser pipes) to the surface
3.39
hydraulic conductivity
capacity of subsurface materials (sand, rock etc.) to allow a fluid (i.e. water) to flow through it. For an
isotropic porous medium and homogenous fluid, the volume of water that moves in unit time under a
unit hydraulic gradient through a unit area measured at right angles to the direction of flow
Note 1 to entry: In the SI System, the units are m3/s/m2 or m/s.
3.40
hydraulic head [m]
height above a datum plane (such as sea level) of the top of the column of water that can be supported by
the hydraulic pressure at a given point in a ground water system. For a well, the hydraulic head is equal
to the distance between the water level in the well and the datum plane
3.41
impermeable
resistant to flow of or penetration by water or other liquids
3.42
injection well
well constructed for the purpose of injecting water directly into the aquifer
3.43
kelly
long square or hexagonal steel bar connecting the rotary table with the drill string enabling rotary
motion, while allowing the drill string to be lowered or raised during rotation
3.44
Managed Aquifer Recharge
MAR
Managed Aquifer Recharge (MAR) is the deliberate recharge of water to aquifers for subsequent recovery
or environmental benefit e.g. achieved through injection wells
3.45
monitoring well
well constructed or used for the purposes of water level or water quality data collection
Note 1 to entry: Monitoring wells are often installed to provide an early warning of contamination occurring
down gradient from a landfill or industrial facility. See also Observation wells.
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
3.46
observation well
well constructed in a specific location for the purpose of observing(measuring) changes in water level
Note 1 to entry: An existing well perhaps drilled for a different purpose may also be used to observe water level
changes. Observation wells are typically used for short duration data collection such as before, during and after an
aquifer test. Wells that are used to collect data on a long term basis are usually referred to as monitoring wells.
3.47
packer
device used to isolate particular portions of the aquifer in a borehole
3.48
partial penetration
when the depth of the intake portion of the well is less than the full thickness of the aquifer
3.49
piezometer
(see monitoring well)
3.50
polymer mud
water based drilling fluid with polymers
3.51
production well
water well designed to meet a particular demand of groundwater
3.52
pumping test
controlled pumping with associated measurements of water level changes that are used to determine
aquifer characteristics and the hydraulic properties of wells
3.53
rig
machine used to drill a well
3.54
rising main
drop pipe
pump column
pipe connecting the submersible pump to the wellhead
3.55
rotary table
revolving or spinning section of the drill floor that provides 3. power to turn the drill string in a clockwise
direction
Note 1 to entry: The rotary motion and power are transmitted through the kelly bushing and the kelly to the drill
string
3.56
saline intrusion
entry of sea water into a coastal aquifer
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
3.57
saline water (salt water)
water that contains significant amounts of dissolved solids (usually more than 1 000 parts per
million (ppm))
3.58
screen
well screen
cylinder usually made of steel or plastic material used to allow water to enter a well while preventing
sediment or rock particles from entering the well
3.59
sieve analysis
determination of the particle-size distribution of a soil, sediment, or rock by measuring the percentage of
the particles that will pass through each sieve in a standard set of sieves
3.60
sinkhole
depression in the land surface caused by collapse of overlying soils or rock into pre-existing cave systems,
usually in areas of limestone geology
3.61
slurry
thin mixture of liquid, especially water, and any of several finely divided substances, such as cement or
clay particles, but capable of pumping
3.62
specific capacity
rate of discharge of a well per unit depth of drawdown. It is used as a measure of well efficiency. The ideal
for a well is high discharge and low drawdown
Note 1 to entry Units are m3/s/m or m2/s.
3.63
static water level
static or rest water level is the level at which water stands in a well when the water level is at equilibrium
with atmospheric pressures when it is not under the influence of a pumping nor an injection
Note 1 to entry: It is a measure of the depth from the ground surface or from a known reference point to the water
level. The water level may also be measured relative to a datum such as sea level (see also, dynamic water level)
3.64
subsidence
dropping of the land surface as a result of over-pumping ground water. Cracks and fissures can appear in
the land
Note 1 to entry: Subsidence is usually an irreversible process.
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
3.65
suspended sediment/particles
soil particles that remain in suspension in water for a considerable period of time without falling to the
bottom under the force of gravity
Note 1 to entry: Such material remains in suspension due to the upward components of turbulence and currents
and/or by suspension.
3.66
test well
reconnaissance borehole
pilot borehole
exploratory borehole
well used to assess and/or test the geologic and hydraulic properties of an aquifer. A series of test wells
may be drilled in order to determine the most effective location for a (much more expensive) production
well
Note 1 to entry: Test wells are usually of a smaller diameter than production wells.
3.67
top drive drilling
drilling rotary method in which the rotary motion is provided by a mechanical device (hydraulic pressure
head) located at the swivel and which moves vertically up and down the mast. It is a recent alternative to
the rotary table and kelly drive
3.68
transmissivity
rate at which groundwater can flow through an aquifer section of unit width under a unit hydraulic
gradient. It is the average hydraulic conductivity of a section of the entire aquifer at a given location
multiplied by the thickness of the producing formation
Note 1 to entry: Units are m2/day.
3.69
tremie pipe
pipe used to carry materials (usually grout) to a specific depth in a drilled hole. Tremie pipes are slowly
withdrawn as the grout is placed in the well
3.70
unconfined aquifer
aquifer with an upper surface as a water table whose piezometric surface is at atmospheric pressure (an
unconfined surface)
Note 1 to entry: The level of this groundwater can fluctuate, creating a saturated zone and an unsaturated zone
3.71
uniformity coefficient
d /d
40 90
ratio used to characterise a sediment using a plotted grain-size distribution curve, derived from sieving.
It is the 40 % retained size divided by the 90 % retained size
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
3.72
verticality
deviation from an imaginary vertical line from the ground surface to the centre of the earth
Note 1 to entry: Usually measured in meters or centimeters.
3.73
water table
surface of a body of unconfined groundwater at which the pressure is equal to that of the atmosphere.
The static water level in a well in an unconfined aquifer
3.74
well development
application of techniques after and during the drilling process that bring the well to its maximum yield
capacity and achieve maximum well efficiency
3.75
well yield
volume of water discharged from a well usually expressed in cubic meters per day (m /day)
3.76
wellhead
equipment/installation used to maintain surface control of a well
4 Project objectives
4.1 Background
Before starting the design of a well or well field, there needs to be a common understanding between the
commissioning party and the designing party with respect to the objectives of the project.
These objectives form a framework for the entire design process, including the evaluation of the design
at the end of the design process to check whether the design meets the project objectives (as explained
in Clause 21) and the construction of the work. Secondly, the requirements form the basis of a contract
between the commissioning party and the designing party. Thus, they also serve as protection for the
customer, especially those that are not very familiar with the design of wells. Finally, the requirements
may also be used for communication with third parties who depend on the design of the well. For
example, the well discharge may be the important input for a company that is responsible for the
transmission of pumped water above ground surface.
4.2 Requirement
Identification of the location and objectives of the well as well as for the timeframe of the project.
4.3 Compliance
These following aspects shall be formulated in a document, such as a specification sheet or tender
document. Both design and commissioning party shall go through the document and agree consensually
on it.
— The location of the well. This shall either be defined in the form of georeferenced discrete point or as
an area for the project defined as a polygon of georeferenced points.
— The purpose of well: for the pumping, injection, infiltration or as an observation well.
oSIST prEN 18049-1:2024
prEN 18049-1:2024 (E)
— The required flowrate and/or required water level. This shall be defined as a discrete number or as
a range.
— The theoretical minimum technical life span for the well.
— The minimum required water quality properties of the abstracted water. These shall be in line with
the purpose of the well and other requirements of the commissioning party.
— Interface with the above-ground installation. For example the water pressure and pipe diameter at
the well head.
— Check if additional requirements arise from an existing legal framework
— Check if there are additional requirements, depending on the purpose of the well (see examples in
Annex A).
— A concrete time schedule or at least a timeframe. The time schedule shall at least indicate when the
wells need to be drilled and when they need to be operational, and address both the dimensi
...