Bioremediation ofSurface Water inWadi Hanifah

• Wadi Hanifah is the mostsignificant natural landmark inthe region.

• The Wadi extends 120 kmfrom the northwest to thesoutheast of Riyadh.

• 4500 square km catchmentbasin.

• 60% of the developed area incity inside it catchment.

• Wadi Hanifah is the maindrainage for the city .

Historical Background

• The Wadi Hanifah was a sourceof water to surroundingcommunities for centuries

• In the past there was a balancebetween the Wadi resourcesand human needs

Historical Background: cont’d

Protection of the Wadi

• In 1987 the High Commissiondirected the ArriyadhDevelopment Authority (ADA)to acquire the wadi as aprotected area under themanagement of the ADAdevelopment programs whichtake many actions to stop thedeterioration

Action taken by ADA

• Strategy for Wadi Hanifah in1994 .

• Stop all sources of pollution

• Stop industrial activities alongthe Wadi Hanifah

• Stop mining activities

• Define floodplain boundaries

• Limit the placement of utilities

• Monitor the wadi environment

Action taken by ADA

• Planning for the Future:In2003 ADA Finalized andapproved the Wadi HanifahComprehensiveDevelopment Plan(WHCDP)

WHCDP: Objectives

• Protection and preservation ofthe Wadi Hanifah valley

• Rehabilitation of floodplainand drainage basin

• Maintain and preservehistorical and heritage sites

• Create a sustainable balancebetween the Wadi ecosystemand the City’s needs

• Improve the quality of life

• Use of Wadi as an open spacefor the City

• The Wadi Hanifah Restorationproject is the foundation onwhich it will build the rest ofthe future developmentprograms, such as recyclingwater use, development of theagricultural economy and thedevelopment of open space inthe Wadi.

Wadi Hanifah Restoration Project: objective

FutureGenerations

Riyadh

Wadi Hanifah Restoration Project: Main components

• Cleaning of Wadi bed of alldumping

• Improve flood performance ofthe channel by re-profiling andre-grading

• Channelization of water

• Cleaning the surfacewater (Bioremediation)

• Improving the Wadi roadnetwork

• Naturalization of Wadi bed

• Wadi parks

Water Resource In Wadi Hanifah:

Total : 436000m3

• NDC 33000

• Umm Qasser 5000

• Gudhwanah 6000

• Sultanah 4500

• Swaidi 6000

• Wship 7000

• Namar 9000

• AlShafa 4500

• AlBatha 370000

• Groundwater flows entering WadiHanifah have high nutrient andcoliform bacteria concentrations.

• Vigorous bio-assimilation through acomplex food web would result insubstantially cleaner water over thelength of the flow channel .

• Therefore nutrient assimilation andcoliform die-off is the goal ofbioremediation.

Water Quality Background:

Bioremediation: Objectives

• Reduction of Fecal and TotalColiform Level

• Prevention of cumulativenegative impact of nutrientsloads through the wadi

• Elimination of bad odors ofwater

• Establishment of aquaticecosystem

• Dry weather flow channel (DWFC).

• Bioremediation system

Bioremediation: Approach

Wadi Channel: DWFC

• Stone-lined trapezoidalchannels, providinghabitat and sustenancefor benthic invertebratesand consumer speciesliving among the rocks

• Developed every 500 metersto improve oxygenation andprovide both habitat andfood for fish.

• Harvesting fish removesnutrients bio-accumulatedthrough the enhanced foodweb.

Wadi Channel: Step Weirs and Pools

Bioremediation System

Bioremediation Process:

• This naturally occurringprocess can be augmented inwastewater systems throughthe establishment of anecologically efficient food webconsisting of not only primaryproducers (algae and higherplants) but also consumerorganisms (fish, birds, insects,etc).

Bioremediation Facility: Main Components

• Physical Components :different section of facilitysuch as inlet pools, biocellsand outlet pools.

• Mechanical Components :aeration system, fountainsystem and APBS.

• Biological Components :Fishes, invertebrates,microbes and birds.

Physical Components: Bioremediation Facility Overview

HEADPOOL

OutletPOOL

BiocellGroup 1

Trainingwall

BiocellGroup 3

BiocellGroup 2

Gate

Physical Components: Group 1

• Inlet Pool

• 1 Inlet Channel

• 20 Bio-cells

• 2 Outlet Channels

Physical Components: Group 2

• 1 Inlet channel

• 34 Bio-cells

• 2 Outlet Channels

Physical Components: Group 3

• 2 Inlet Channels

• 80 Bio-cells

• 3 Outlet Channels

• Outlet PoolOutletPOOL

A

A

Gate

AA

InletChannel

BiocellHeadPool

CentralMarsh

Channel

RiffleZone

Section A-A:

OutletChannel

Bioremediation Process: Bio-cells components

• Biocell Head Pool

• Central Marsh Channel

• Riffle Zone

Riffle Zone

Central MarshChannel

Biocell Head Pool

Bioremediation Process: Inlet channel

Pump air in the inlet channel to :

• Provide dissolved oxygen (DO) forliving organisms - Organismsconsume and convert organicmaterial in the water column(carbon and nitrogen).

• Kill pathogenic bacteria (fecalcoliform) with high dissolvedoxygen levels.

• Provide optimum habitat for fish.

• Provide aggressive mixing to limittoxic blue green algae.

• Provide aggressive mixing to achievecomplete mix conditions in influentchannels – improve reaction kinetics.

Bioremediation Process: Inlet channel

• Provides habitat for complexfood web.

• Contains installed APBS tomaximize nutrientassimilation into communityand small fish feeding.

Bioremediation Process: Bio-cell Head Pool

Bioremediation Process: Central Marsh Channel

• Provides additional aquaticand benthic habitat.

• Creates habitat for predators,such as herons andkingfishers that feed on smallfish, invertebrates and plants.

• Is planted with shrubs thatalso act as effectivephytoremediators.

• De-nitrification in the bottomparts

Bioremediation Process: Riffle Zone

• Provides water mixing,oxygenation and smallorganism habitat.

• De-nitrification in the bottomparts

Bioremediation Process: Outflow Channels

• After passing through thebiocells water collects ineither of two side collectorchannels which thenconverge on a new group ofbiocells.

MECHANICAL COMPONENTS:

• AERATION SYSTEM • FOUNTAIN SYSTEM

• ARTIFICIAL PERIPHYTON BENTHIC SUBSTRATE (APBS)

BIOLOGICAL COMPONENTS

• BIRDS

• FISHES

• INVERTEBRATES

• MICROBES

• VEGETATIONS

BIOREMEDIATION SYSTEM MONITERING

• Water Flow

• Water quality

• Sedimentation Rate

• Aquatic EcosystemEstablishment ( fish,invertebrates, birds andvegetations

Monthly Flow at the influent of the facility

MONTHLY AVERAGE LEVEL AT INFLUENT & EFFLUENTOF BIOREMEDIATION FACILITY

MONTHLY AVERAGE LEVEL AT INFLUENT & EFFLUENTOF BIOREMEDIATION FACILITY

MONTHLY AVERAGE LEVEL AT INFLUENT & EFFLUENTOF BIOREMEDIATION FACILITY

MONTHLY AVERAGE LEVEL AT INFLUENT & EFFLUENTOF BIOREMEDIATION FACILITY

MONTHLY AVERAGE LEVEL AT INFLUENT & EFFLUENTOF BIOREMEDIATION FACILITY

MONTHLY AVERAGE LEVEL AT INFLUENT & EFFLUENTOF BIOREMEDIATION FACILITY

MONTHLY AVERAGE LEVEL AT INFLUENT & EFFLUENTOF BIOREMEDIATION FACILITY

BIOREMEDIATION PERFORMANCE EFFICIENCY

CONCLUSION:

• The facility is performing well in level reductionof important parameters such as : SuspendedSolids, Organics (BOD), Ammonia-N, TKN, TotalPhosphorous and Fecal Coliform .

• The facility is successful in nutrients assimilationinto higher level of food chain (migratory birds)with its established biodiversity.

• The system is functioning with out odour in thewater at the effluent.

• The facility has created an aesthetic landmarkin the center of highly urbanized city of Riyadh

THE END