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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
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
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)
Drains and Beach Health
Contaminants in Stormwater drains
Pathways of discharge
Water (and sed) quality
– persistence over time
Contaminants in Stormwater Discharge, and Associated Sediments, at Perth’s Marine Beaches
DoW Internet: Water Quality →→→→Stormwater →→→→Quality