In the past, Vietnamese people just threw their rubbish on the ground near them. This was no problem when all the rubbish was natural - banana leaf wrappings, food-scraps, etc. Either the animals ate the scraps, or they simply decomposed into the soil.
The problem now is that this practice has remained, but the rubbish is different. Now there are disposable plastic bags, cans, packaging, etc. Whilst the city has a huge team of garbage collectors at work every day, they only work along the street. The rivers miss out and pile up with non-biodegradable "stuff".
Take a look.
I've often seen people throw plastic bags filled with rubbish over their back wall into a stream or lake. I've seen people pour leftover housepaint into a lake. Or funnel all the detergent-filled water from a motorbike-cleaning business straight into the stream next door.
The collective understanding that we in Australia have in regards to the environment simply hasn't happened yet.
