Chapter 5 - Sewage & Debris Pollution

7/29/2019 Chapter 5 - Sewage & Debris Pollution

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Dr. Ong Meng Chuan

Department of Marine Science

Faculty of Maritime Studies and Marine ScienceUniversiti Malaysia Terengganu


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Chapter 5: Sewage & Debris Pollution

Aquatic Pollution | MMS 3202 2

CHAPTER 5

SEWAGE & DEBRIS POLLUTION

SEWAGE POLLUTION

Sewage waste is created by residences, institutions, hospitals, commercial andindustrial establishments

Industrial sources of wastewater often require specialized treatment processes

Major pollutants in the rivers of Asian countries is the domestic sewage Major constituents of sewage are :

o A large portions are organic matter in dissolved, suspended or settable solidforms

o This will give high BOD and low DO or it could cause anoxic condition. Highmortality of fish or organism may be found

Sewage is one of the most significant pollutants affecting the coastalenvironments especially in the developing nations

Sewage includes everything that goes down the kitchen, laundry and

bathrooms sink, as well as what is flushed down the toilet

Sewage is mostly made up of water approximately 99.5%


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The major contributor is human sewage from population center that is dischargedfrom waste treatments plants:

o The inadequate number of sewage treatment plants in operationo Poor operating conditions of available treatment plantso Disposal practices of discharging mostly untreated wastewater

The discharge of sewage can cause public health problems either from contactwith polluted waters or from consumption of contaminated fish or shellfish

The discharge of untreated sewage effluents also produce long-term adverseimpacts on the ecology of critical coastal ecosystems in localized areas due to the

contribution ofnutrients and other pollutants

The typical pollutants in sewage effluents are suspended solids, oxygendemanding substances, nitrogen, phosphorus, oil, grease and pathogens

Industrial wastewater has a wider range of pollutants, which are dependent on thetype of industry producing the waste

o Food processing industry oxygen demanding substanceso Chemical industry toxic substances

Pollution due to inadequate sewage disposal causes nutrient enrichment aroundpopulation centers possible will cause eutrophication or red-tide

High level of chemical nutrients mainly nitrogen and phosphorus Increase nutrient concentrations promote increased algal and bacterial growth,

degradation of seagrass and coral reef ecosystems, decreased fisheries

production, along with risks to human health

High amount of bacteria may contain pathogenic species and cause contaminationto shellfishes and other organism, and render water to be unsafe for recreation and

aquaculture

Presence of detergents, oil and greases, heavy metals and other chemicals whichmay be toxic to the aquatic organism or they may be bioaccumulated in the

organism through food chains and become toxic to human

High level of suspended particle are found cause reduction of primaryproductivity and suffocation of the benthic organism


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SEWAGE / WASTE TREATMENT

What microorganism is used in sewage treatment process?

BACTERIA

The sewage treatment involves several stages, called preliminary, primary,secondary and tertiary treatment

The final effluent can be discharged into a stream, river, bay, lagoon or wetland, orit can be used for the irrigation of a golf course or park

If it is sufficiently clean, it can also be used for agricultural purposes.

SEWAGE / WASTE TREATMENT IN MALAYSIA

Preliminary Sewage Treatment

Deal with large solids, which are removed by screening or ore, macerated andreturned to the sewage flow

Screening and grinding for the removal of debris and rags, grit removal bysedimentation and flotation for the removal of excess oil and grease

Primary Sewage Treatment

Screening and sedimentation remove some of the suspended solid and organicmatter

It is initially filtered to remove large, non-biodegradable solids by passage throughbar screens.


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Secondary Sewage Treatment

Remove biodegradable organic and suspended solids,mainly using biological processes

Based on maximizing (activating) the growth ofaerobicheterotrophic bacteria, fungi and protozoa such thatthey break down the dissolved organics and/or

incorporate them into new microbial cells (biomass)

which then settle out of suspension, together with

undigested material, as "sludge

Since the desired microbial populations are aerobic, it iscrucial that the system be highly aerated

Tertiary Sewage Treatment

Remove nutrient, toxic substances including heavy metals andfurther removal of suspended solids and organics

The now nearly purified water flows from the post-secondarysedimentation tanks into a large basin, where it is chlorinated to

kill any remaining potential pathogens

Finally, any remaining solids are left to sink to the bottom of a tank and theeffluent will flow out

The treated wastewater is now safe to be released into rivers, lakes and seas. But what left is the sludge which need to be dried by pressing, drying or burning Sludge is also an excellentsoil conditioner for plant


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WHAT IS AQUATIC DEBRIS

Aquatic debris is any man-made objectintentionally or unintentionally discarded,disposed of or abandoned thatenters the aquatic environment

Also known as litter, is human created waste that has deliberately or accidentallybeen released in the lake, river, sea, ocean or waterway.

Marine environment : 80% of debris originates onshore and 20% from offshoresources


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Marine debris is something in the marine environment (ocean and beach) that doesnot naturally occur there

More technical definition according to National Oceanic and AtmosphericAdministration (NOAA) is :

any persistent solid material that is manufactured or processed and directly,

intentionally or unintentionally, disposed of or abandoned into the marine

environment

Floating oceanic debris tends to accumulate at the center of gyres and oncoastlines known as beach litter

Deliberate disposal of wastes at sea is called ocean dumping Naturally occurring debris, such as driftwood are also present the aquatic

environment

Aquatic debris is a problem with no geographical boundaries Although various countries have had a more publicized problem, persistent aquatic

debris can be found on just about every coast and waterway in the world


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TYPE OF AQUATIC DEBRIS

Plastic

As society has developed new uses for plastics, the variety and quantity of plasticitems found in the marine environment has increased dramatically

These products range from common domestic material (bags, cups, bottles, balloons)to industrial products (strapping bands, plastic sheeting, hard hats, resin pellets) to

lost or discarded fishing gear (nets, buoys, traps, lines).

Glass, Metal, Styrofoam, and Rubber

These materials are similar to plastic in that they are used for a wide range ofproducts


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While they can be worn away broken down into smaller and smaller fragments,they generally do not biodegrade entirely

As these materials are used commonly in our society, their occurrence as marinedebris is overwhelming

Derelict Fishing Gear

Derelict fishing gear (DFG) refers to nets, lines, crab/shrimppots, and other recreational or commercial fishing equipment

that has been lost, abandoned, or discarded in the marine

environment.

Modern gear is generally made of synthetic materials and metal,and lost gear can persist for a very long time.

Derelict Vessels

Thousands of abandoned and derelict vessels litter ports,waterways and estuaries, creating a threat to navigation,

recreation, and the environment.

Many vessels end up sinking at moorings, semi-submerged inthe intertidal zone, or stranding on shorelines, on reefs or in

marshes, and breaking apart


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EXAMPLE OF AQUATIC DEBRIS

Plastic bags Plastic containers

Plastic pellets Styrofoam Cloths

Abundance fishinggears

Tires

Medical waste Glass bottles Balloons

Appliances andmachinery

Food packaging

Cigarette butts andlighters

ETC

Plastic Doesn't Belong in Our Oceans, It Belongs in Your Recycling Bins


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HOW DEBRIS ENTER THE AQUATIC ENVIRONMENT

Land-based Sources Indirectly when washed out to the ocean via rivers, streams and

storm drains

Littering, Dumping, and Poor Waste Management Practices Intentional orunintentional disposal of domestic or industrial wastes on land or in rivers or

streams

Storm Water Discharges Storm drains carry this water and debris to a nearby river,stream, canal, or even directly to the ocean

Extreme Natural Events Hurricanes, tsunamis, floods and mudslides havedevastating effects on human life and property

Ocean-based source Directly by illegal dumping or accidental loss of debris from a

ship and stationary platform


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Fishing Vessels Fishing gear may be lost from commercial fishing vessels as well asfrom recreational boats

Stationary Platforms Offshore oil and gas platforms are surrounded by water, andall items lost from these structures become marine debris

Cargo Ships and Other Vessels Cargo lost overboard from freighters, cruise shipsand other vessels poses serious threats to marine navigation

Estimated 10,000 containers at sea each year are lost by container ships, usuallyduring storms

One famous spillage occurred in the Pacific Ocean in 1992, when thousandsof rubber ducks and other toys went overboard during a storm. The toys have since

been found all over the world, providing a better understanding of ocean currents

Similar incidents have happened before, such as when Hansa Carrier dropped 21containers in 1990 (with one notably containing buoyant Nike shoes) Great Shoe

Spill of 1990

COMMON CAUSES AND SOURCES

Illegal dumping Onshore industries Offshore oil and gas operation Unsecure garbage bins Improper disposal

Recreational boaters Commercial vessels Cumulative small-scale sources Event balloon releases Carelessness


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DEBRIS CHARACTERISTIC

Some types of debris persistin aquatic environment for extremely long periods


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Floating debris can be

transported by water current

on the surface or in the water

column

Other debris sinks and remains on the sea floor

THREATS OF MARINE DEBRIS

Marine debris threatens both people and wildlife

On the beach, people can step on debris such as broken glass, and children can putdebris like discarded cigarette butts into their mouths. In the water, debris can

damage boats and present a safety hazard for divers

Marine debris threatens wildlife through entanglement and ingestion. Animalssuch as whales and sea turtles have died from ingesting items such as plastic bag


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MARINE DEBRIS : AFFECTS MARINE LIFE

Each year, many species of marine animal, including sea birds, marine mammals andsea turtles die from becoming entangled in marine debris or ingesting marine

debris they have mistaken for food

Entanglement and ingestion of marine debris can harm marine lifeo Entanglement an animal gets ensnared in the loops and opening of debriso Ingestion an animal can mistake marine debris for food, accidentally ingest it,

and degraded debris can be ingested by filter-feeding organisms

o Smothering marine debris may disrupt feeding, reproduction, movement orseverely impair the health of sessile animals

ENTANGLEMENT

Entanglement can occur :o Accidentallyo When animal is curious about an object or using it for shelter

Harmful to marine organism because it can :o Cause drowningo Disrupt or prevent feedingo Restrict movement or ability to swimo Increase vulnerability to predatorso Result in infection or loss of limbs


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ENTANGLEMENT EXAMPLE

Derelict fishing gear, rope and strapping bands are common items thatentangle marine organism

Ghost nets, lost or abandoned fishing nets hundreds of meters long, threatenprotected species and other marine organism

Ghost nets often become concentrated in relatively small areas by wind andcurrents and can continue ghost fishing for extremely long periods


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INGESTION

Ingestion can occuro Accidentallyo When an animal feeds on debris thatlook like food

Harmful to marine organism because it can :o Blockages of the esophagus and intestinal tract can kill organismo Sharp object can cause injuries and infectionso Toxins can accumulate in an animals tissue affecting the health and wellness of

the organism

INGESTION EXAMPLE

Seabird and hatchling sea turtles may eat plastic debris that is toxic, resulting inreproductive failure or death

Sea turtle may mistake floating debris for food, which can lead to suffocation orintestinal blockage

Whale can ingest marine debris that can become entangled in the baleen, causechoking or interfere with digestion

MARINE DEBRIS : AFFECTS HABITAT

Debris can damage coral reefs, seagrasss, mangrove area and other protectedhabitats

o Marine debris can break or damage coralo Floating debris can carry non-native species long distance that can alter habitats

and ecosystem

o Marine debris can block sunlight and prevent the growth of sea grass beds andcoral reefs

Marine debris can cause obstruction or alter important habitat used for shelter,feeding or reproduction

MARINE DEBRIS HUMAN

Human dump more than 14 billion pounds of garbage each year into the worldsocean

Pacific Whale Foundation


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HUMAN - EXAMPLE

Navigation submerged of floating debris can pose navigational hazards orentangle vessel propellers

Human health and safety injure swimmers when stepped on, or entangle diversand swimmers, endangering their lives

Local economy result in lost tourism revenue Industrial damaging vessels and equipment

THINGS WE SHOULD KNOW ABOUT MARINE DEBRIS

Degradable / Not degradable It comes in many forms Marine debris can hurt or kill animals Hazard to human This is a global problem It's your problem, too Small steps lead to big results

3R

Recycle, Reduce, Reuse

Documents

Chapter 5 - Sewage & Debris Pollution