PARENT SESSION
Oral Session #37: River and Riparian Restoration II.
Presiding: J. Berg
Tuesday, August 6. 1:00 PM to 4:00 PM. Mohave Meeting Room, TCC.

Use of riffle formations to restore montane streams in Arizona.

Medina, Alvin^*,1, Long, Jonathan^2,3, Steed, James¹, ¹ Rocky Mountain Research Station, Flagstaff, AZ² Northern Arizona University, Flagstaff, AZ³ White Mountain Apache Tribe, White River, AZ

ABSTRACT- Many montane meadow streams of the southwest have undergone channel incision causing lowering of the water table that favors mesic, often exotic, plant species over native hydric species. We describe a restoration technique that restores stream functions and processes by mimicking natural hydrologic and geomorphic dynamics. The riffle formation technique consists of placing heterogenous mixtures of cobbles and gravels at prescibed intervals, and then shaping the formations and securing them with native sedge transplants. Through testing on a suite of streams in the White Mountains of eastern Arizona, this technique has proved to be a practical, economical, and socially acceptable restoration approach. Keys to success include: 1) clear understanding of the hydrology and geomorphology of the stream reach in question to ensure that riffle formations are appropriate in number, dimension, and placement; 2) promoting rapid establishment of anchoring vegetation; 3) periodic maintenance and adjustment of riffle formations; and 4) reducing grazing impacts during the recovery period. The technique is applicable to both pool-riffle stream types (<2%) and step-pool types (>2%).

KEY WORDS: riparian restoration, montane meadows, southwest