A series of interconnected stories about citizens adjusting to the new normal after an earthquake that destroyed 1500 hundred buildings and killed 185 people in Christchurch, New Zealand.

Naming both the place and the disaster has helped the logline, however because there is no lead character it is hard for me to come up with a good logline example but here would be my attempt:
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"When a terrible earthquake destroys Christchurch New Zealand, the survivors must rebuild their town and their lives while facing increasingly more difficult problems in the process."

It would be hard to sell a concept about "...a series of interconnected stories...", unless you've got private financing I suggest you take that out of the logline. As Richiev and DPG wrote above, best to structure a story around a single main character and their goal.
Is there one particular story of the 1500 that stands out to you? Perhaps consider this as your main story.
Best to tell a powerful story of one person as a metaphor for many, as appose to lots of small stories that would repeat the same theme.

What Richiev said. It's almost always better to hang several stories on the clothesline/story line of a lead character's struggle.

As that great non-humanitarian Joseph Stalin ?said , the death of one person is a tragedy, the death of a million ?is merely a statistic. ?James Cameron understand the dramatic truth of that when he hung the deaths of 1500 people in the sinking of the Titanic?on the clothesline/story line of the fate of 2 star-crossed lovers.

And ?characters don't "adjust" in ?drama. ?They struggle. ?Against overwhelming odds to not merely survive but prevail. ?In this case, they would be struggling to survive and rebuild.

fwiw