What’s in Storm Water

Malcolm RobbWater Science Branch

Contaminant surveys of storm water

Water Science Branch

Knowing water quality matters• All Stormwater is to some degree

contaminated• Water reuse options are dependent on

knowing with what• Many drains include industrial and

septage discharges

Contaminants

1. Organic compounds and metals

2. Major ions and microbial parameters

3. Nutrients

Parameter Source Characteristics and toxicity

Polycyclic aromatic hydrocarbons(PAHs)

Incomplete combustion of fuels, garbage + other organic substances; components of oils, creosote, roofing tar, dyes, plastics + pesticides.

Toxic, disrupt hormonal systems, damage genes, foetal abnormalities + carcinogenic e.g. fish – fin erosion, liver abnormalities, immune system impairmentsAbility to bioaccumulate

Total petroleum Originate from crude oil Toxicity to aquatic life not well documented

Organic compounds and metals

Total petroleum hydrocarbons(TPH)

Originate from crude oil

Most likely to enter environment from road runoff containing vehicle fuel + oils

Toxicity to aquatic life not well documented

Organochlorine pesticides(OCs)

Organophosphorus pesticides (OPs)

Applied to crops, livestock, buildings + pets to protect from insect damage.

Importation, manufacture + use of OCs -phased out in Australia – but highly persistent – so still exist

Toxic - serious short-term + long-term impacts at low concentrationsImmune system + reproductive damage

Disrupt hormonal systems, fertility problems + foetal abnormalitiescarcinogenic + damage genes

Parameter Source Characteristics and toxicity

Herbicides Applications to crops, lawns, parks, roadside verges + golf courses to destroy, control or inhibit the growth of plant pests (weeds)

Direct toxic effects – hormone disrupting, e.g. abnormal sexual development in frogs, carcinogenic + can damage genesIndirect effects on a waterway – kill aquatic plants – reductions in DO etc

Organic compounds and metals

cont’d

plants – reductions in DO etc

Polychlorinated biphenyls (PCBs)

Dielectric fluids for capacitors + transformers, heat transfer + hydraulic fluids, lubrications, additives in pesticides, paints, adhesives + plasticsA ban on the importation of PCBs into Australia since 1979

Toxic, hormone disrupting, can cause gene damage, carcinogenic + can cause foetal abnormalitiesHighly persistent; ability to bioaccumulateUbiquitous e.g. reported even in polar bear flesh in the Arctic

Anionic surfactants

Discharge of aqueous wastes form household + industrial laundering operations + in herbicide mixtures

Toxic to aquatic life

Metals (suite of 14)

Housing materials, atmospheric pollutants, industry, components of fuel + through tyre, brake + engine wear

Range of toxic responses eg. developmental deformities + mortality in oysters - Cd

Major ions and bacteria

Parameter Source Characteristics and toxicity

Bacteria Faeces of domestic + wild animals; human faeces through sewer overflow

Can lead to human illness – ear, eye, nose, throat + skin diseases; + gastrointestinal disorders

Major ions e.g. sulphates contributed from fertilisers or acid sulphate runoff

Major ions can change the characteristics of the water column resulting in changes in toxicity of other contaminants present e.g. metals

Nutrients such as nitrogen and phosphorus

Characterising the

Swan Canning System

– Nutrient contamination such as elevated nitrogen and phosphorus levels is well understood.

– Non-nutrient contamination – few ad hoc studies often relating to specific events such as fishkills in a particular location e.g. downstream from the Bayswater Drain (2003). And LGA reports

– Before this study there was no broad understanding of non-nutrient contamination as a whole in this system.

– Lack of information addressing spatial variability and a broad spectrum of non-nutrient contaminants.

DoW - Water Science Technical Series reports: 3, 4, 5, 6,

Read all about it

http://www.water.wa.gov.au/Waterways+health/Understanding+our+rivers+and+estuaries/Monitoring+and+assessing+waterways+health/default.aspx

Objective:to establish– Types– Quantities

Catchment Drainage Assessment

– Quantities – Spatial variability

of a broad range of contaminants

entering via storm water drains

Water quality

Sediment quality

77 sites within 31 subcatchments

Each site sampled 4 times

44 individual drain sites drain sites within Swan Catchment

33 individual drain sites within the Canning Catchm ent

Broad range of drain sites:

ConstructedConcrete channels

Mills St Main Drain outlet to Wilson Wetland

South Belmont

Perth Airport South Maylands

Compensating basins

Central BelmontLower Canning – Manly St

South Belmont Lower Canning – Lynwood AvenueLower Canning – Edgeware

Streams, brooks and creeks with environmental values

Ellen BrookUpper Swan – Minchin Creek

Ellen Brook

Bannister Creek Bull CreekHelena River

Findings:

• Some contaminants typically only found in the sediments such as PAHs, petroleum hydrocarbons and OC pesticides

• Some typically in the surface waters such as • Some typically in the surface waters such as bacteria, herbicides, and anionic surfactants

• Some in both sediments and surface waters such as metals (exception: mercury only in sediments)

• Some not detected at all at the current detection limits such as PCBs

– Absence of uncontaminated sites to compare to, the data were compared with ANZECC guidelines

– NOTE: there are currently no guidelines for contami nants in stormwater for WA

– Ecosystem Health guidelines (where available)

Priority Rankings

– Ecosystem Health guidelines (where available)Relevance: Swan Canning System considered ecologica lly sensitive; many of the sites were streams, creeks and brooks – syste ms with environmental values

– Recreational Water Quality guidelines - bacteria pre sent in the waterRelevance: many of these sites are used as recreati onal areas by children. Also, downstream areas used by kayakers, swimmers e tc

– Published studies in the peer reviewed scientific l iterature

– Guidelines applied here are to be used as INDICATOR only and to help us to prioritise subcatchments

Prioritisation

number of measured variables where number of measured variables where guidelines were exceeded and/or where concentrations were consistently high, in addition to potential for ecological harm based on the variable type .

Five higher priority subcatchments:

Upper SwanOC pesticides, herbicides, metals

+ possible issue with petroleum hydrocarbons, anionic surfactants

Helena RiverPAHs, OC pesticides, metals

+ possible issue with herbicides

Central Belmont Main DrainOC pesticides, metals

+ possible issue with herbicides, PAHs,petroleum hydrocarbons

Mills Street Main DrainOC pesticides, metals

+ possible issue with herbicides, PAHs,petroleum hydrocarbons

Lower CanningOC pesticides, metals

+ possible issue with anionic surfactants,PAHs, petroleum hydrocarbons

Non-Nutrient Contaminants Program Current and Future Work:

Overall NNCP - “Multiple Lines of Evidence” Approach

Groundwater Assessment

Recommended

Follow up drains WQ for biological available

fractions

Status: complete

Status: currently underway

Catchment Drainage Assessment

Recommended Biological Assessments:

Ecological studiesEcotoxicological investigations at 2 sitesBioaccumulation studies

Sediment Survey within Estuary

Passive Sampler Assessment

Ecotoxicological studies at 2 sites,

bioaccumulation at 1Ecotox,sediments, ecology at 1 site

Passive samplers at 10 sites

Passive Samplers• 8 key subcatchments• Range of contaminants including Herbicides, Pestici des, PAHs• Can detect contaminants at trace levels (ng/L)• Time integrated load over a designated period• Collaboration with National Research Centre for Env ironmental

Toxicology

Groundwater Assessment

• 3 reclaimed landfill sites adjacent to the Swan Canning river system

• 22 sites• Range of contaminants including metals, organics,

nutrients

Bicentennial Adenia Park (Riverton) Woodbridge Riverside Park (Woodbridge) Bayswater Riverside Gardens (Bayswater)

Estuary Sediments

Drains and Beach Health

Contaminants in Stormwater drains

Pathways of discharge

Water (and sed) quality

– persistence over time

The Catchment

65 drains Winter 04-05

Scarborough Beach

Contaminants in Stormwater Discharge, and Associated Sediments, at Perth’s Marine Beaches

DoW Internet: Water Quality →→→→Stormwater →→→→Quality