transfer data from parcel points to closest downstream pipe

[RyanGreenway]

So I have a municipal sewer system (pipes, manholes, etc.) where the pipes are drawn directionally.  We have water usage data on parcel points (basically each parcel has 1 or more points representing each water service account on that parcel with a water use number, over 21,000 parcel points).  We would like to somehow automate summing and transferring that usage data to either the closest pipe or to the closest downstream manhole.  The issues I see with going from parcel point to closest manhole is the closest manhole could be upstream of the connection and send the flow to the wrong point or if the closest manhole is on a different street.  So I feel parcel point to sewer main would be the best way and even then you run into issues on street corners.  The problem I have is we don't have sewer service lines to know which street/pipe each sewer service is on.  If I did I would have used either the service line or a node at the connection between the service and the main line to put that account usage data on.  I currently have water modeling software that can pull parcel point data to the closest model node but like i said this would be pretty inaccurate.  Does anyone know if something like this can be done?

[MikeMillerGIS]

You could leverage the auto add lateral tool to generate the connections from the parcel point to the pipes.

Water Utility Network Editing toolbar - Water Geometric Network Editing and Analysis | ArcGIS Soluti... 

You might have to adjust some lines were they connect to the wrong main.

You can then could use the Flow Accumulation tools to sum up the weights of each parcel point

Water Utility Network Reporting toolbar - Water Utility Network Editing and Analysis | ArcGIS Soluti... 

[RyanGreenway]

Thanks...I have thought about using a tool to auto generate sewer services from the parcel points to the nearest sewer main (I believe we have done that before but I can't remember the process) but for over 21,000 points it would be a nightmare to fix all the errors generated from the automation...I am working on a desktop basic license so I can't build geometric networks and I don't think I have access to the water utility network editing and analysis toolbar...but we do have a couple people with publisher licenses if that is available for those kind of licenses

[MartinPflanz]

Ryan,

The quest for a 1:1 match to the real-world - it has trade offs as you just mentioned (cleaning up data for 21K points!) yes that would be an adventure.  I will make a generalization from the sewer modeling perspective, that for every effort to step closer to the real-world with a virtual model, there is a required effort and a particular return that you should evaluate (is the improved precision worth the effort?).  In my experience, for most sewer network modeling cases, nearest pipe or nearest node would suffice - when you add in the inflow and infiltration (this a > value) along pipe lengths required when sizing sewer networks for peak flow, you will see even less difference between the 3 methods you could choose from.  Also the noise or local miss-assignment from one node or pipe to another near-by is offset by load from another few parcels that a node picks up.  If you "zoom out" to a particular neighborhood, whether you assigned sewer loading using the manual match up method, auto-nearest node, or auto-nearest pipe, often there is no difference in flow leaving in neighborhood sewer mains, aka your choice at the microscopic level can become nearly indistinguishable at the mid and macro level - re: not worth tweaking 21K points.  Then there is that whole magic number trust of where the actual loading of sewer data came from - estimated conversion from water meter data or a mysterious coefficient based on persons per household  - hope you get my point... the core data sanitary sewer loading is already based on generalized assumptions.    Beyond the tools Mike mentioned, there are also modern Sewer Network Modeling tools, that can provide over half a dozen ways to do the work for you and automagically load manholes with sanitary sewer loads, by population, area, meter connections etc, so it may be best to identify when a more precise loading may be needed or not - use the right tool for the purpose. 

Test:  

• sizing pipes in a neighborhood for peak wet weather flows? work towards 1:1 only if there is value doing so
• working on a master plan exhibit or general visual of the dry weather sanitary sewer? 1:1 not needed, KISS rule