Sweetwater Preserve

The Sweetwater Preserve is an 894-acre sanctuary located in the foothills of the Tucson Mountains. With the help of this story map, we would like to share the Sweetwater Preserve with you - from seeing its often-reclusive wildlife and unique vegetation to learning the history of the area and exploring its extensive trails system. We hope you enjoy the journey and better yet, come and visit our easily accessible public park and experience all it has to offer firsthand.

Over 14 miles of trails crisscross the 894 acres of Sweetwater Preserve and are open to the public from dawn to dusk. These trails are all multiuse and open to horses, dog walkers, mountain bikers, and people on foot. They are generally unimproved and may be steep in some areas. Hikers will walk among the saguaros and have many opportunities for photos.

If you are new to the desert, you will want to take it easy on your first few outings. Here are some tips for a successful hike.

• Bring plenty of water
• Use sunscreen and a hat
• Snacks - especially salty food
• Bring a first aid kit with a whistle or signal mirror
• Reference  a map  - while many trails are well marked, maps are still very helpful tools!

Due to our great weather, biking is a year-round activity. During the busiest season (January, February, March) over 10,000 trail users enjoy Sweetwater Preserve per month. Trails are well-marked with signs and can be enjoyed as an out-and-back trip or linked together for a unique loop experience.

🚲 Use the map below to see the trails and plan your trip.

There are no previously recorded archaeological or historical sites found within the preserve’s boundaries. Even though the early inhabitants did not leave many signs in the preserve, they affected the local fauna and flora of the region through selective hunting and gathering practices. Agriculture became more common about 3,000 years ago. Europeans introduced new plants and animals which continued to change the desert landscape. More recently, waves of miners, ranchers and farmers began settling the area changing the region further.

In 1927 Joseph Fraps homesteaded the site. To fulfill the requirements of the 1862 Homestead Act, Mr. Fraps dug a well, built and lived in a one-room wooden shack with a metal roof, raised goats on the land, and paid $18 in fees and commissions.

The Civilian Conservation Corps built fifty-two check dams and other water and erosion control features in the preserve in the 1930s, and even though many are now silted-in, the dams still slow the flow of ground water which benefits the plants and animals that live there.

Large-scale urban growth accelerated in the last few decades and urban sprawl threatened to blot out vast sections of the wild desert. Concerned citizens proposed creating the Sweetwater Preserve to conserve this remarkable diversity in plant and animal life for everyone to enjoy.

In 2001, Arizona was the second fastest growing state in the country. Developers built 23 subdivisions in the Tucson Mountains at that time, and the community living in the area of the Preserve recognized the threat of urban sprawl. They proposed the acquisition and creation of Sweetwater Preserve to combat the sprawl as well as protect existing habitat and provide opportunities for public use of the area.

Land was acquired using money from the voter approved 2004 Open Space Bond and Sweetwater Preserve was established for the provision and conservation of valuable wildlife habitat and open space.

In 2020 the National Park Service acquired land connecting Saguaro National Park to the preserve.

Constant exposure to sun, wind and water have combined with geologic forces over millions of years to create the jumbled mix of arroyos, mesas, playas, expansive plains, jagged cliff faces, alluvial fans and sandy river valley. Consequently, the Sonoran Desert is composed of igneous, sedimentary, and metamorphic rocks of varying ages. Numerous active volcanoes once dotted the desert landscape millions of years ago. Much of this topography is still seen throughout the Sweetwater Preserve. Hilly topography and rocky outcrops make up the landscape of the preserve, characteristic of Basin and Range geography.

 The preserve is in the Sonoran Deserts desert scrub biome. Common plants here include agave, ocotillo, jojoba, creosote, wolfberry, and bursage as well as various trees such as palo verde, mesquite, and ironwood. The area is home to a multitude of cactus ranging from the soaring saguaro cactus (Carnegiea gigantea) to the tiny mammillaria (Mammillaria spp).

Other common cacti species include:

• Fishhook barrel (Ferocactus wislizenii)
• Staghorn cholla (Opuntia versicolor)
• Pinkflower hedgehog (Echinocereus fendleri var. fasciculatus)
• Engelman's prickly pear (Opuntia engelmannii)
• Teddybear cholla (Opuntia bigelovii)
• Chainfruit "jumping" cholla (Opuntia fulgida)

Cacti provide food and shelter to many of the inhabitants that thrive in the Sonoran Desert. Many of the flora display beautiful flowers of reds, pinks, yellows and whites blooming from February through June, depending on seasonal temperatures. Dense stands of saguaros populate Sweetwater Preserve; during the summer dry season, these plants provide a great source of fruit to the numerous creatures that live there.

Like all animals that live in the Sonoran Desert, mammals that live in Sweetwater Preserve have adapted to the desert’s high temperatures and limited water supply. Some like jackrabbits have large ears to help radiate heat away; others burrow underground during the day and come out at night to hunt. Below and at right are some of the mammals you may see during your journey through Sweetwater Preserve.

Another small mammal found in and around Sweetwater Preserve is the bat. There are at least 11 species of bats known to frequent the Tucson Mountains and surrounding areas. These bats are essential to the desert environment because they are important pollinators of agaves and cacti, including the saguaro. The Sweetwater Preserve provides a perfect safe haven for the endangered lesser long-nosed bats as well as other bat species on their annual migrations from Mexico to the Sonoran desert.

Numerous species of reptiles and amphibians roam Sweetwater Preserve along with one species of tortoise – the desert tortoise. Places like the Preserve help keep the tortoise off the Endangered Species list by providing vital habitat. Arizona state law describes the desert tortoise, as well as the Gila monster, to be “Protected Native Wildlife”, which means these species may not be killed or collected without a permit. So if you are hiking in the Preserve, please do not pick up any of the wildlife. It can be dangerous to you as well as to them.

Southern Arizona is a hot spot of bird diversity and Sweetwater Preserve is no exception. Some common birds you may see are Anna’s Hummingbird, Cooper’s Hawk, Gambel’s Quail, Gila Woodpecker, and Curve-billed Thrasher. The Cactus Wren, a large noisy wren, builds its football shaped grass nest in the cholla. The Harris’ Hawk is a medium sized bird of prey that hunts in packs, one of the only hawks to do so. During a hike in the winter, you might hear the lovely song of the seasonal visitor Phainopepla, a shiny black bird with a distinct crest and red eyes. If you are interested in bird watching, be sure to bring your bird book and binoculars and see how many different species you can find!

You might catch a glimpse of a longhorned beetle, a desert cicada, or even a bumblebee as you explore the trails in the Sweetwater Preserve. Butterflies are out in full force during annual migration season, visiting the beautiful desert flowers and showing off the stunning colors of their wings.

Bumblebees, digger bees, and cactus bees are crucial for pollination of native plants found in the Preserve. And if you’re visiting the area for a hike in the Preserve, check with local vendors for some tasty Mesquite honey – thanks to those wonderful bees!

Want to see more information? Have a look at the links below for more details about visiting Sweetwater Preserve, a Pima County Conservation Lands & Resources Park.

 Pima.gov 

 Google Maps