About 80 homes were first evacuated on Sunday after residents in a northwest side subdivision reported that the ground was caving behind several houses. No one was injured.
The large crack in the retaining wall sent soil tumbling out below. Fences were tossed askew and crumpled like accordions, and aerial photos showed land had given way near the foundations of several homes.
Engineers at the scene Monday were trying to determine why the ground was shifting and how much damage it could cause.
Fire Department District Chief Nim Kidd said at least seven streets had to be closed since the ground started shifting on Friday. Kidd estimated the ground has been slipping at the rate of about 4 inches an hour.
The homes were in a new subdivision built by Pulte Homes Inc. The homebuilder was providing lodging and meals for the evacuated residents, company spokeswoman Valerie Dolenga said Monday.