You have two residents in your community who for whatever reason do not get along. Unfortunately they live right across the street from one another!

Your homeowners association manager receives phone calls and emails from these two weekly. Bill calls to complain about the lights on in Dan’s home. Dan calls to complain about cars parked on the street when Bill’s wife threw him a birthday party (and didn’t invite Dan). 

Your manager has received complaints from both owners for things such as loud music, a barking dog, driving too fast, kids playing in the backyard pool, damage to landscaping when one neighbor backed a trailer out of their driveway, hitting a hedge across the street, a tree that drops pine needles into the neighbor’s yard and many more.

What is the Association supposed to do about all of these issues and the time it’s taking the manager to deal with them?

You should investigate the complaints and decide if the complaints are truly a nuisance or just an annoyance. 

[E]very annoyance or disturbance of a landowner from the use made of property by a neighbor does not constitute a nuisance. The question is not whether the plaintiffs have been annoyed or disturbed ... but whether there has been an injury to their legal rights. People who live in organized communities must of necessity suffer some inconvenience and annoyance from their neighbors and must submit to annoyances consequent upon the reasonable use of property by others. (Schild v. Rubin (1991) 232 Cal.App.3d 755 , 764.) (Source: Davis Stirling.com)

If the investigation determines that it’s a nuisance the HOA board must take action

Some of these may be violations and are probably addressed in the Associations governing documents in the nuisance provisions. Your manager can send a violation notice to the offending owner directing them to change their ways or face hearings and fines.

If the determination is that it’s not a violation of the Association documents then the owners will need to be informed that the issue is something that they will need to try to work out between themselves.  You can offer to schedule a time when they can meet on neutral ground to discuss and work things out.

Your management team can help you to adopt rules or guidelines for how to handle these disputes between neighbors that are specific to your homeowners association.