NORTH SALT LAKE — Heavy rains early Thursday caused flooding in parts of Salt Lake and Davis counties, as well as an accident involving two semi trucks that closed a portion of I-215.

But city leaders in North Salt Lake say the storm did not impact the landslide on Parkway Drive, where repairs have yet to begin.

Overnight, North Salt Lake received at least 4/5 of an inch of rain, according to KSL meteorologist Grant Weyman.

The rain caused mud to flow in an area west of the slide where homes are under construction. However, the slide itself has remained mostly unmoved despite multiple heavy rainstorms since the hill collapsed more than 11 months ago, according to City Manager Barry Edwards.

"We had a lot of rain, but the storm system seems to be able to take care of it," he said.

But geotechnical engineers say the longer the hillside goes unrepaired, the greater the likelihood the hill could move again, especially near the vertical scarp at the crest of the hill.

"What we've found is these types of flash rain events don't really impact the depth of the groundwater that we're measuring, and they haven't caused any movement," said Tim Thompson, senior geologist with GeoStrata. "What our main concern was is if left as they are, these types of events can erode the scarp, make it unstable and make big pieces eventually fall off. The toe, if it's not cleaned up, eventually that will start to erode, and we don't want to see that occur."

Last month, the city, the developer and two gas companies came to an agreement on how to fund a $2 million remediation plan, which would lay the hill back to a more gradual slope and put a retaining wall at the bottom of the hill.

During negotiations, Eaglepointe Development was sued for damages by the Eagleridge Tennis and Swim Club, which still has debris sitting on its tennis courts, and Kern River Gas. In response, the developer named resident Paul Evans as another defendant, blaming the family for "excessive and extreme" water use that contributed to the hill's demise.

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Developers blame homeowner, others for landslide

Developers on a hillside of North Salt Lake that came down in a landslide are now pointing to a homeowner, among others, whose backyard split away, saying he watered his lawn too much last year, contributing to the problem.

The tennis club has also declined to participate in the city's remediation plan, partly because of a new retaining wall that will have to be built on the property. As a result, the club will be responsible for engineering the repair of its portion of the hill, Edwards said.

"We won't build anything on their property because we can't get permission to get on their property," he said. "They really haven't shared with us what their plans are."

The lawsuits have added to delays in beginning construction, but once the project begins, further delays will be unlikely, according to Edwards.

"We think we have agreement on everything, it's just getting all the attorneys to agree on all the language (of the plan), and there's a lot of players, so there's a lot of attorneys," he said.

Rising groundwater would be the primary reason for another mass movement from the slide, according to Thompson. Rainstorms there have had little impact on groundwater levels, which typically rise and fall gradually with months of moisture or drought.

But until the slide's repair, tension cracks as wide as 12 inches and as deep as 30 feet continue to collect rainwater, adding weight to the soil and risk to the neighbors, Thompson said.

"Pieces could fall off, and that's a health hazard, a risk if somebody's near it," he said. "When things break, you can't predict how they're going to break."

It's still unclear exactly when the remediation will begin. But the final product will eliminate the risks of falling debris and minimize the likelihood of future erosion and movement, Thompson said.

"Getting all the cracks in the landslide all graded and filled in will increase the possibility of rainwater to just run off and not infiltrate, and that's what we'd like to see," he said.

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