Come up with a way to handle if `sum(site_pop) > total_pop`

[kaitejohnson]

Goal

In general, this shouldn't be the case and we should make sure to at least throw a warning to users because its probably something wrong with their input data. However, we also probably want something to work around this if this is the case, since we did see this in production pipeline last season. We just don't want it to happen silently.

Requirements

• [ ] warning message if sum(site_pop) > total_pop within wastewater input data valdation
• [ ] workaround in pre processing: @ChiragKumar9 suggests we might still consider a model where there is still a subpopulation not covered by wastewater (but how to choose the proportion of the total pop that is?)

[seabbs]

Can you try and roughly do some estimation of cross catchment contamination?

[kaitejohnson]

I'm not sure -- I think you could use county fip codes potentially, but the reality is that a wastewater catchment area could be touching multiple counties and not be overlapping.

The one instance that we see this is in a very small jurisdiction -- my guess is that the wwtp serves people in other states so its actually not overlapping just extending beyond the jurisdictional pop.

I think for a package though, we mostly want to make sure this is flagged bc further investigation would need to happen outside of the package