Agua Fria River Petroglyphs

Arizona Water: limited perennial stream reaches and vulnerability to baseflow loss due to increased reliance on ground water requires careful management to assure the sustainability of water resources, community character, and long-term economic health of Arizona.

Wet/Dry Mapping Resource Page


wet dry training

Welcome to the Arizona NEMO Wet/Dry Mapping Resource Page!
Here you will find the handouts used for Wet/Dry mapping on the Agua Fria River and other useful information.

Download Riparian Monitoring Handbook


Arizona NEMO's Wet/Dry Training Video now available for download

These are the handouts from the training and mapping.

Wet/Dry Monitoring Instructions (includes GPS instructions)
30 foot rule
Data collection forms
Graphic of Wet/Dry reaches on the San Pedro River
Graphic of Wet/Dry reaches of the Agua Fria River


The protocol we are using was developed by the Nature Conservancy and the BLM to map the wet/dry reaches on the San Pedro River through the San Pedro Riparian National Conservation Area (SPRNCA). They have been mapping the river since 1999. In 2004, they produced a report showing their results. In 2007, Arizona NEMO helped expand the mapping north of the SPRNCA. In 2008, Arizona NEMO and the BLM expanded the mapping to include 30 miles of the Agua Fria River in cooperation with the Upper Agua Fria Watershed Partnership, Friends of the Agua Fria National Monument, the Arizona Riparian Council, and local citizens on this project.

For more information contact Terry Sprouse.

UTM Information




UTM, Universal Transverse Mercator, is a system of world coordinates like latitude and longitude, from 80 degrees south latitude to 84 degrees north latitude, except the measurements are in meters and UTM lines are orthogonal (always at right-angles to each other). This projection makes all latitude and longitude lines (except the central meridians) curved.


Unlike the regular Mercator, "Transverse Mercator" is a projection with the cylinders rotated 90 Deg (to east-west) and touch the earth "universally" at 60 "central meridian" longitudes. Coordinates are "UTM northing" and "UTM easting."


UTM Northing is the distance north from the equator in meters and Easting is the distance east from 60 central meridians of 6-degree-wide zones starting at longitude 180 degrees.


UTM Northing is divided into 8-degree-high zones from 80 Deg. south latitude to 84 Deg. north latitude using the letters C thru X with the equator at M/N. A,B and Y,Z are reserved for the UPS coordinate system at the poles. For a map of UTM zones see (HERE).


All UTM coordinates are POSITIVE by incorporating a system of "false" easting and northing. Adding an arbitrary 500,000m to the central meridians and 10,000,000m to the distance south of the equator in the southern hemisphere keeps all readings positive.


The UTM map scale increases to either side of the central meridian, so the scale is reduced to 0.9996. This way there will be two meridians to either side of the central meridian where the scale will be correct which improves the average map scale accuracy.


The original definition of the meter was 1/10,000,000th the distance from the equator to the north pole (which is no longer exact.) Due to the oblate shape of the earth, UTM (WGS-84 datum) northing for 45 Deg. N latitude is 4,986,272m instead of 5,000,000m. For UTM (NAD-27 datum) the northing value is 4,986,055m.


This 217m difference is related to the UTM northing errors of approximately 200m experienced by posters here on the NG with some DRG maps. This is due the program, GPS, or user selecting the wrong datum.


Map of UTM Zones