How to decontaminate a garden after a sewage spill?

[MessySurfaces]

I posted this in the gardening forum, but putting it here too for traffic, I'd be very grateful for any advice!

On Saturday we woke up to sewage flooding the alley behind our house, and filtering down into our garden. most of what actually came into our garden was the water (most of the solids being caught by the fence thank goodness).
The council duly came out and sorted the flood, and are supposed to be doing some sort of cleanup, but that is proving harder to arrange.
The water soaked into one flower bed, across a paved area, and under some decking tiles (and a bit into the shed)
I've a toddler and a preschooler, so lots of scrabbling about and getting grubby, and we often eat at a table on the decking. I'm not sure what sort of cleanup to expect/demand?? How can you even make earth safe that has had raw sewage on? Or am I being a bit crazy and actually it's fine, just part of normal grubbiness??

Hi - I'm a garden designer but don't have to deal with poo too often! For this, I would get

1. dog poo bags - physically lift and remove any solids, bin them as per dog poo.
2. hose pipe with jet spray - rinse of any hard surfaces just using a jet, you could add a small squirt of mild detergent like washing up liquid, scrub with a yard brush
3. hose pipe with sprinkler - hose your lawn area a little or use a sprinkler, the turf with just drink up liquid waste. Rake off and bag any remaining solids. Keep kids off for a week, let the smell dissipate and a rain fall or two to occur. FACT: soil contains millions of organic bacteria that can harm human health irrespective of sewerage contamination.....so it's kind of not clean anyway and sensible precautions and handwashing should apply to toddlers etc.

if it's on garden soil or grass, the vast array of ferocious microrganisms will gobble it up in next to no time.

don't use bleach or disinfectant, which will interrupt this natural decay and cleaning.

I'd hose off any hard surfaces such as concrete or paving with ordinary clean water.

You might like to keep children or pets off it for a week as they will tread sewage into the house on their feet.

...too slow!

Hah- thank you both! I have done step one (and noted lots of good fat worms in the soil, which I take to mean it's in good health and equipped with plenty of healthily ferocious microbes to deal with the sewage-water). I shall have a go at point two tomorrow when DD is asleep.
I am hoping that the sunshine we are having will be on our side- lots of good UV to knock out things which would rather live in guts. The kids are most miffed not to be allowed out in it though!

Jeyes fluid can be used in the garden. I think it's smells lovely!