A Minefield of Geologic Hazards

The Standard Examiner today had an article about lots being developed in "hillside protection zones" in North Ogden City. Apparently, the city has not given clear indication of what kind of treatment development in these zones require.

It would serve our cities best to pay close attention to common possible risks associated with developing in our region.

Here is a list of landslides and debris flows up through 1992 in the Ogden area (click to enlarge):


Clearly building to close to moving dirt can put homes in harms way.

Here is another interesting diagram:

Much of the neighborhood south of the Dee Event Center is build on a giant rock slide from Beus Canyon.

Earthquake hazards are also unavoidable in Utah. I thought this diagram was interesting because it shows what happens to the water table and land elevations in the event of an earthquake.


The moral of this diagram is that neighborhoods in Syracuse, West Point, Hooper, and parts of Farr West and Plain City are going to be in real trouble if an earthquake strikes. These cities are at very low elevation in relation the the lake. The developers also dug basements for these homes. Many of the homes I have showed in these areas have sump pumps to keep water from seeping into the basements. If an earthquake strikes, you are going to need more than a sump pump to keep the water out.

Finally, there is the hazard of building on fault lines. Here is a photo of the mouth of Ogden Canyon looking south in 1909. Look at that nice fault line winding its way up the bench.

The East bleachers at Weber State University are built on top of a 60 foot vertical fault scarp (one of the largest exposed scarps in Weber County).

Material courtesy USGS and Field Guide To Geologic Excursions in Utah and Adjacent Areas of Nevada, Idaho, and Wyoming, G.S.A. field guide, Rocky Mountain Section, edited by J.R. Wilson, 481 p., 1992 $16.95 MP-92-3