Setting up laser to measure floodplain Measuring Channel Bottom

Rapid Stream Riparian Assessment (RSRA)

To view RSRA data for Patagonia Lake:  PLSP 2016-2021 Score Comparison

On May 1, 2021, a team of eight volunteers conducted the 4th RSRA on a portion of Sonoita Creek just above Patagonia Lake. FOSC Treasurer Dave Christiana coordinated the effort which involved a lot of upfront planning; gathering needed equipment, coordinating volunteers and re-locating  and flagging the "Study Reach" using coordinates from past assessments.  Prior to heading out to the Study Reach FOSC Science Advisor Kathy Pasierb gave a brief synopsis for the new volunteers of the importance of RSRA and the data obtained from the research. The day started at 8:00am and ended about 4:00pm. This included the group sitting down together to discuss their findings and record them on the score sheet.

Measuring Floodplain Connection and Inundation

Disturbingly, due to over grazing at the park, much of the young under story flora was heavily browsed and the creek bank was heavily disturbed. Because of the lack of food cows were eating poison hemlock growing along the creek. We saw one dead cow in the creek and a week later a second dead cow was reported. If over grazing continues the health of this portion of the creek as well as the lake will be compromised.

RSRA History

RSRA was developed by a team of scientists looking for a way to quickly and accurately measure  existing conditions of lower elevation stream-riparian ecosystems in the inter-mountain west. If problems are discovered, management strategies and restoration efforts can be put into place to mitigate any further issues and work toward building a healthier stream.

Check out the User's Guide for Rapid Stream Riparian Assessment:  RSRA User's Guide

In the spring of 2015 FOSC conducted our first RSRA on Sonoita Creek in the Patagonia-Sonoita Creek Preserve. We went back again in the spring of 2016 and 2019 and surveyed the same stretch of creek per protocol. Our findings were that there was little change in the creek during those surveyed years.

In October of 2016 ten people in two teams conducted a RSRA on Sonoita Creek upstream from Patagonia Lake and downstream from a head cut. We went back to re-survey the area in April 2017 and 2019. Our findings were that the head cut is moving upstream and the stream is severely entrenched and much of the bank in our study reach was unstable. The resulting sediment increase can disrupt ecosystems if it gets too high.

We try to do a RSRA yearly so if interested in being trained and helping us with our efforts please contact: or

Wet/Dry Mapping

Next Wet/Dry Mapping Surveys :

June 4, 2022 - Harshaw Creek,  Patagonia, AZ                                           
June 5, 2022 - Sonoita Creek
Contact Dave Christian at 602-903-8296 or email at to sign up or for questions


June 5, 2021-FOSC conducted the first Wet/Dry mapping of Harshaw Creek!

Twelve volunteers showed up early Saturday morning to conduct the first Wet/Dry mapping of Harshaw Creek.

Splitting into three teams of four, with one designated driver for each team, the three groups hop-scotched over each other to map most of the approximately 15 miles of creek bed. Achieving permission from most of the land owners was crucial and allowed us to get a good assessment of the topography of the creek bed as well locations of surface water in the creek. In order to take a measurement we needed at least 30 feet of continuous flowing surface water and the only place we found that was in the section of creek that flows along Harshaw Creek Road. The Nature Conservancy graciously gave us GPS units to record the locations of any water we found.

FOSC Science Advisor, Kathy Pasierb, also brought along a water monitoring kit and we learned how to measure the turbidity (which measures the amount of particles in the water), PH and dissolved oxygen in the creek.

Data will be uploaded into a data base by Dave Christiana, FOSC Secretary/Treasurer, and available for all who want the info.

Wet/Dry mapping provides a snapshot for monitoring flow conditions in streams with interrupted surface flow. It can flag changes in local groundwater conditions and may provide early warning of ecological changes. Wet/Dry mapping, spearheaded in Arizona by The Nature Conservancy, has been conducted on the San Pedro River for over 12 years.


For more information on Wet/Dry Mapping: Wet/Dry Mapping Info

Taking a GPS reading


Checking water PH level

Measuring Turbidity

Start of wet sections on Harshaw Creek

June 26, 2021- FOSC conducted the first Wet/Dry Mapping of Sonoita Creek!

Ten volunteers conducted a Wet/Dry mapping survey on Sonoita Creek covering about 3 miles; beginning at the confluence of Harshaw Creek and Sonoita Creek down to the end of The Nature Conservancy property, just before Temporal wash.  What was surprising to some of us was that the portion of the creek that flows through The Nature Conservancy had dry spots. Had prior years Wet/Dry Mapping been done we know if this was typical or not. There were plenty of fish in the creek, Speckled Dace, Longfin Dace and possibly Desert Sucker along with butterflies, birdsong, and a Great Blue Heron overseeing our efforts.

We plan to conduct Wet/Dry Mapping yearly, possibly more, so email FOSC at if you are interested in helping us in the future.  

Checking water quality


Overseeing FOSC efforts on the creek

It was great to see fish in the creek

Lots of duckweed in the creek

Western Diamondback Rattlesnake-waiting