Stormwater - Not just rain to drain

Pedestrians and motorists dropping rubbish, including cigarette butts.
Packaging from businesses and building sites.
Illegal dumping.
Blows out of bins and uncovered trailers.

Blocks drains.
Looks ugly.
Smothers plants.
Chokes, injures and kills animals.
Can injure people.

Deciduous street trees.
Gardens and parks.
People deliberately dumping leaves in gutters or waterways.

Block drains.
Shade aquatic plants and animals.
Change water colour.
As they rot they become slimy and smelly, and use up oxygen in the water.
Release nutrients.

Grass clippings

Deliberate dumping.
People not sweeping up gutters after mowing.
Cut grass washing off parks and gardens.

Shade aquatic plants and animals.
Change water colour.
As they rot they become slimy and smelly, and use up oxygen in the water.
Release nutrients.

Soil and silt

Roads.
Gardens.
Building sites.
Cleared land.
Erosion.
Stock walking in river beds or along river banks.
Carp stirring up sediment.

Makes waterways shallower and changes their shape.
Smothers plants and animals on the bottom.
Blocks sunlight to plants in the water.
Humans and animals can't see through the water.
Changes water colour.

Detergents

Washing cars or other things on or near the road or driveways.
Cleaning boats in or near waterways.

Reduce surface tension of water, affecting some aquatic macro-invertebrates and frogs.
Creates foam.
Contains nutrients.
May have chemicals which are poisonous for wildlife.
Looks ugly.

Oil/grease

Leaking engines (vehicles and boats).
Cleaning vehicles on or near roadways.
Accidental spills.
Deliberate dumping.

Smothers plants and animals.
Creates a slick on the surface which can reduce the amount of sunlight or oxygen entering the water.
Looks ugly.
Makes animals sick or kills them.
Not nice to swim in.

Petrol

Leaking vehicles.
Boats.
Washed off roadways and service stations.
Spills.
Deliberate dumping.

Poisons animals and plants.
Not safe for drinking.
Smells.
Can injure humans.

Animal droppings

Livestock with access to waterways.
People not cleaning up after their pets.
Washed from properties, parks or gardens into waterways.

Smells.
Changes the water colour.
May contain chemicals from medicines such as flea tablets which can kill aquatic life.
May contain viruses and bacteria which can make animals and humans sick.
Have high nutrient levels.

Heavy metals
(eg copper, lead, zinc, chromium)

Car brakes, tyres and exhaust fumes.
Industrial activities, chemical spills or dumping.

At certain levels can cause illness or death in animals and humans.
Remains in sediment and builds up in the food chain.

Pesticides

Carried by the wind or washed off plants.
Sprayed leaves that have fallen.
Spills.
Cleaning of pesticide equipment near roads or waterways.
Deliberate dumping of chemicals or their containers.

Pollutes waterways and groundwater.
May kill aquatic plants and animals, and animals drinking from waterways.
Poisonous to humans.

Detergents.
Plant matter.
Some soils.
Animal droppings.
Treated sewage and septic tank overflow.
Chemical spills.
Fertiliser.

Can cause nuisance plant and algal growth.
This can then smother other plants, block sunlight, use up oxygen and smell when they break down.