8 billion litres of raw sewage is not that much...it's only the equivalent of ~3,000 olympic-sized swimming pools (each measuring 50mx25mx2m and containing 2.5million litres)
http://www.patagoniaalliance.org/wp-content/uploads/2014/08/How-much-water-does-an-Olympic-sized-swimming-pool-hold.pdf
For those that have trouble visualizing , that's equivalent to a lake 2metres deep, 1.25km wide and 3km long .
For those who have ever seen the behemoth 1000-footer super-freighters that travel the Great Lakes , those vessels are between 1000 and 1013.5 feet (305 and 309 m) long, 105 feet (32 m) wide and of 56 feet (17 m) hull depth, and have a volume 0f ~168 million litres.
One would have to empty 7 of those vessels every day for a week to release the equivalent 8 billion litres .
Alternatively, that's nearly the same volume as could be contained by 3 Empire State buildings .
Cheers,
Luker