"Can somebody explain the purpose of the "Our Lewisham, Our Say" survey? I had a look at it and the budgets they're asking about total roughly 25% of Lewisham's £900M budget, yet if you disagree with ony cut, you are asked to reallocate it to one of the other categories within that 25%."
The £900m (actually £1.1bn last year) figure is the gross budget, ie including income and expenditure on providing some services and a lot government grant income that passes straight through the council as expenditure on statutory services (housing, schools etc).
The 25% is looking at the net figure, around £280m, which is called the 'net controllable budget', which, as it suggests, is the budget which the council has most control over. This is funded by council tax (about £90m), unringfenced government grants (about £50m) and Lewisham's share of the national non-domestic rates redistribution (about £140m). It's these last two sources of income (as well as some of the pass-through grants) that are being cut, hence we're being asked to look at savings within those services funded by them.
Personally, I would like to see the council take a much broader look at all the services being provided (including those funded through the 'pass-through' grants I mentioned above), as there may well be savings that could be made through restructuring how they are delivered in toto. However, although I believe there is some thought being put in to this behind the scenes, the 'Our place, Our say' process doesn't encompass this at all.