Project Description

Project Site

The SCRP site is located in Flagstaff, Arizona adjacent to Highway 180 (N. Fort Valley Rd.). Lower Schultz Creek is depicted below in Figure 1 running southwest before entering a large box-shaped culvert under the highway.

Figure 1: SCRP Site Aerial Photo (Google, 2013)

On the south bank of the channel displayed in Figure 1 lies the American Conservation Experience (ACE) Office. The parcel of land shown north of the ACE Office is owned and managed as a wildlife migratory corridor by the Museum of Northern Arizona (MNA). The culvert location and orientation are represented by the orange arrow in the site aerial photo.

Currently, the culvert at the project site is unaligned with the direction of the channel. As a result, the channel bank below the northern edge of the ACE office parking lot has become increasingly steep, entrenched and unstable. Contributing to the unstable channel conditions is a headcut over a foot tall, located in the channel bed directly below the parking lot. Eventually, the parking lot edge will become undercut and fail due to the unstable banks. The entrenched and eroding bank below the parking lot is depicted below in Figure 2.

Figure 2: Unstable Bank at Culvert

While the culvert is not shown above in Figure 2, it is positioned just a few feet out and to the right of the photo. The bumper of the white cargo van in this figure lies directly over the northern-most edge of the parking lot. Also displayed above in Figure 2 is the large cluster of native Coyote Willows. The headcut below the parking lot previously mentioned is located in the channel bed just behind this willow corridor. Due to the willows growing deep into the channel, migration of the headcut has been slowed.

Project Objectives

In addition to the channel conditions described in the above sections, the motivation for implementing a channel restoration design on Schultz Creek began in hopes of achieving the following objectives:

• To realign lower Shultz Creek with the Highway 180 culvert
• To stabilize the actively eroding and entrenched channel banks at the SCRP site
• To restore the channel to its natural state by reactivating the floodplain and preserving the integrity of the surrounding riparian environment.

Constraints and Considerations

Although lower Shultz Creek is dry and not flowing under normal conditions, one major storm event could lead to a negative impact on the already unstable channel. Furthermore, if a catastrophic fire in the Shultz Creek watershed were to be followed by a major storm event, resulting flows would have an unpredictably large toll on the channel, and almost certainly cause failure of the ACE parking lot.