WATER SUPPLY SYSTEM WATER SUPPLY SYSTEM BASIC OPERATIONSBASIC OPERATIONS

Prepared by RCAP SolutionsPrepared by RCAP Solutions

For PADEPFor PADEP

22

IntroductionIntroduction

Basics of Water SupplyBasics of Water Supply

33

Drinking Water SourcesDrinking Water Sources

Surface WaterSurface Water

GroundwaterGroundwater

44

Surface Water: AdvantagesSurface Water: Advantages

Easily accessibleEasily accessible

Large volumes of waterLarge volumes of water

Surface reservoirs for storageSurface reservoirs for storage

55

Surface Water: DisadvantagesSurface Water: Disadvantages

Exposure to contaminantsExposure to contaminants

Expensive filtrationExpensive filtration

66

Groundwater: AdvantagesGroundwater: Advantages

Less treatmentLess treatment

ConsistencyConsistency

AvailabilityAvailability

77

Groundwater: DisadvantagesGroundwater: Disadvantages

Chemical contamination Chemical contamination

HardnessHardness

Multiple wells Multiple wells

LocationLocation

88

Groundwater Treatment ProcessesGroundwater Treatment Processes

99

Groundwater Treatment ProcessesGroundwater Treatment Processes

Not very complexNot very complex

Mainly disinfectionMainly disinfection

Covered laterCovered later

1010

Surface Water Treatment ProcessesSurface Water Treatment Processes

1111

Racks and ScreensRacks and Screens

1212

Racks and ScreensRacks and Screens

Prevent debrisPrevent debris

Pipes and pumpsPipes and pumps

Straining pastaStraining pasta

1313

MixingMixing

1414

MixingMixing

Coagulant Coagulant

Suspended particlesSuspended particles

1515

Coagulation and FlocculationCoagulation and Flocculation

1616

Coagulation and FlocculationCoagulation and Flocculation

Reduces solidsReduces solids

Prevents bacterial “hiding”Prevents bacterial “hiding”

Like making cheeseLike making cheese

1717

SedimentationSedimentation

1818

SedimentationSedimentation

PresedimentationPresedimentation

BasinsBasins

Solids loading reductionSolids loading reduction

Sludge removalSludge removal

1919

FiltrationFiltration

2020

FiltrationFiltration

Solids and floc removalSolids and floc removal

PhysicalPhysical

ChemicalChemical

BiologicalBiological

2121

Types of FiltrationTypes of Filtration

Slow SandSlow Sand

Conventional FiltrationConventional Filtration

2222

Types of FiltrationTypes of Filtration

Direct FiltrationDirect Filtration

Diatomaceous EarthDiatomaceous Earth

2323

Types of FiltrationTypes of Filtration

Membrane FiltrationMembrane Filtration

Bag and Cartridge FiltersBag and Cartridge Filters

2424

DisinfectionDisinfection

2525

DisinfectionDisinfection

Disease-causing organismsDisease-causing organisms

ChlorineChlorine

Ozone and Ultraviolet RadiationOzone and Ultraviolet Radiation

2626

Disinfection: ChlorineDisinfection: Chlorine

Chlorine GasChlorine Gas

Sodium HypochloriteSodium Hypochlorite

2727

Disinfection: ChlorineDisinfection: Chlorine

Calcium HypochloriteCalcium Hypochlorite

Chlorine may form carcinogensChlorine may form carcinogens

2828

Disinfection: Ultraviolet LightDisinfection: Ultraviolet Light

Penetrates most cell wallsPenetrates most cell walls

No toxic residualsNo toxic residuals

Short contact times; easy to operateShort contact times; easy to operate

Unsuitable for some water sources Unsuitable for some water sources

2929

Disinfection: OzoneDisinfection: Ozone

OO33

Shorter contact timeShorter contact time

Capital costsCapital costs

O&MO&M

3030

Other Typical Treatment ProcessesOther Typical Treatment Processes

Iron and manganese removalIron and manganese removal

Corrosion controlCorrosion control

These are source dependentThese are source dependent

3131

Iron and Manganese RemovalIron and Manganese Removal

Various techniquesVarious techniques

AerationAeration

Sequestration Sequestration

Ion exchangeIon exchange

3232

Corrosion ControlCorrosion Control

Prevents degradationPrevents degradation

Adjust water characteristicsAdjust water characteristics

3333

ExerciseExercise

Exercise!!!Exercise!!!

Complete the fill-in-the blank questionsComplete the fill-in-the blank questions

3434

Distribution System FacilitiesDistribution System Facilities

PumpsPumps Storage facilitiesStorage facilities Transmission mainsTransmission mains Valves and hydrantsValves and hydrants MetersMeters

3535

PumpsPumps

Provide liftProvide lift

Do not generally create pressureDo not generally create pressure

Major part of O&M costsMajor part of O&M costs

3636

Storage FacilitiesStorage Facilities

Clear wellsClear wells

Stand pipesStand pipes

Elevated storage tanksElevated storage tanks

3737

Clear WellsClear Wells

3838

Clear WellsClear Wells

Large concrete reservoirs Large concrete reservoirs

Constant rate of operationConstant rate of operation

3939

Stand PipesStand Pipes

Located on the groundLocated on the ground

Require little maintenanceRequire little maintenance

4040

Elevated Storage TanksElevated Storage Tanks

Supporting structures Supporting structures

Use gravityUse gravity

Filled in off-peak hoursFilled in off-peak hours

4141

Transmission MainsTransmission MainsSystem DesignSystem Design

Branching systems Branching systems

Loop or grid systemsLoop or grid systems

4242

Transmission MainsTransmission MainsMaterialsMaterials

Cast ironCast iron

Ductile ironDuctile iron

Plastic (polyvinylchloride – PVC) Plastic (polyvinylchloride – PVC)

4343

Valves and HydrantsValves and Hydrants

Valves Valves

Wet barrel hydrants Wet barrel hydrants

Dry barrel hydrantsDry barrel hydrants

4444

MetersMeters

Throughout the system Throughout the system

Used for billing and to identify lossUsed for billing and to identify loss

Lowers usageLowers usage

Replacement program Replacement program

4545

ExerciseExercise

Exercise time!!!Exercise time!!!

Fill in the graphic and answer the questionsFill in the graphic and answer the questions

4646

SummarySummary

Key pointsKey points

4747

References and ResourcesReferences and Resources

See your workbooks for detailsSee your workbooks for details