General EHS Guidelines [Complete version] at: www.ifc.org/ehsguidelines
Environmental, Health, and Safety (EHS) Guidelines
GENERAL EHS GUIDELINES: ENVIRONMENTAL
WATER CONSERVATIONWORLD BANK GROUP

1.4 Water Conservation
Applicability and Approach .............................................33
Water Monitoring and Management................................33
Process Water Reuse and Recycling..............................33
Building Facility Operations ............................................34
Cooling Systems............................................................34
Heating Systems............................................................34

Applicability and Approach

Water Monitoring and Management
The essential elements of a water management program
involve:•Identification, regular measurement, and recording ofprincipal flows within a facility;•Definition and regular review of performance targets, which

Water conservation programs should be implemented

are adjusted to account for changes in major factors

commensurate with the magnitude and cost of water use.

affecting water use (e.g. industrial production rate);

These programs should promote the continuous reduction inwater consumption and achieve savings in the water•targets to identify where action should be taken to reduce

pumping, treatment and disposal costs. Water conservation
measures may include water monitoring/management

Regular comparison of water flows with performancewater use.

Water measurement (metering) should emphasize areas oftechniques; process and cooling/heating water recycling,

greatest water use. Based on review of metering data,reuse, and other techniques; and sanitary water conservation‘unaccounted’ use–indicating major leaks at industrial facilities–techniques.

could be identified.

General recommendations include:

Process Water Reuse and Recycling•

Storm/Rainwater harvesting and use

Opportunities for water savings in industrial processes are•Zero discharge design/Use of treated waste water to behighly industry-specific. However, the following techniques haveincluded in project design processes

all been used successfully, and should be considered in

Use of localized recirculation systems inconjunction with the development of the metering system

plant/facility/shops (as opposed to centralized

described above.

•recirculation system), with provision only for makeupwater•

Use of dry process technologies e.g. dry quenching•

Process water system pressure management•

Project design to have measures for adequate water•

Washing Machines: Many washing machines use large
quantities of hot water. Use can increase as nozzles
become enlarged due to repeated cleaning and /or wear.
Monitor machine water use, compare with specification,and replace nozzles when water and heat use reaches

collection, spill control and leakage control systemlevels warranting such work.
•Water reuse: Common water reuse applications include
countercurrent rinsing, for example in multi-stage washing

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Environmental, Health, and Safety (EHS) Guidelines
GENERAL EHS GUIDELINES: ENVIRONMENTAL
WATER CONSERVATION•

WORLD BANK GROUPand rinsing processes, or reusing waste water from one

the facility, whether sanitary or including other activities

process for another with less exacting watersuch as showering or catering

requirements. For example, using bleaching rinse water•

Regularly maintain plumbing, and identify and repair leaks

for textile washing, or bottle-washer rinse water for•

Shut off water to unused areas

bottle crate washing, or even washing the floor. More•

Install self-closing taps, automatic shut-off valves, spraysophisticated reuse projects requiring treatment of water

nozzles, pressure reducing valves, and water conserving

before reuse are also sometimes practical.

fixtures (e.g. low flow shower heads, faucets, toilets,

Water jets/sprays: If processes use water jets or sprays

urinals; and spring loaded or sensored faucets)(e.g. to keep conveyors clean or to cool product) review•when needed

the accuracy of the spray pattern to prevent
unnecessary water loss.
•Flow control optimization: Industrial processes
sometimes require the use of tanks, which are refilled tocontrol losses. It is often possible to reduce the rate ofwater supply to such tanks, and sometimes to reducetank levels to reduce spillage. If the process uses water

Operate dishwashers and laundries on full loads, and only•

Install water-saving equipment in lavatories, such as lowflow toilets

Cooling Systems
Water conservation opportunities in cooling systems include:•towers rather than once-through cooling systems

cooling sprays, it may be possible to reduce flow while
maintaining cooling performance. Testing can•If hoses are used in cleaning, use flow controls torestrict wasteful water flow

oof water sprayed from hosepipesoUsing flow timers and limit switches to control
water useoUsing ‘clean-up’ practices rather than hosing down

Building Facility Operations
Consumption of building and sanitary water is typically lessthan that used in industrial processes. However, savings canreadily be identified, as outlined below:•accumulation of dissolved solids•Use of air cooling rather than evaporative cooling,although this may increase electricity use in theConsider the use of high pressure, low volume
cleaning systems rather than using large volumes

Limiting condenser or cooling tower blowdown to theminimum required to prevent unacceptable

determine the optimum balance.
oUse of closed circuit cooling systems with cooling

cooling system•

Use of treated waste water for cooling towers•

Reusing/recycling cooling tower blowdown

Heating Systems
Heating systems based on the circulation of low or medium
pressure hot water (which do not consume water) should beclosed. If they do consume water, regular maintenance should
be conducted to check for leaks. However, large quantities ofwater may be used by steam systems, and this can be reducedby the following measures:Compare daily water use per employee to existing
benchmarks taking into consideration the primary use at

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Environmental, Health, and Safety (EHS) Guidelines
GENERAL EHS GUIDELINES: ENVIRONMENTAL
WATER CONSERVATION•WORLD BANK GROUP

Repair of steam and condensate leaks, and repairof all failed steam traps•Return of condensate to the boilerhouse, and useof heat exchangers (with condensate return) rather
than direct steam injection where process permits•

Flash steam recovery•

Minimizing boiler blowdown consistent withmaintaining acceptably low dissolved solids inboiler water. Use of reverse osmosis boiler feedwater treatment substantially reduces the need forboiler blowdown•Minimizing deaerator heating

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