The Sierra Vista Environmental Operations Park (EOP) is the largest water reclamation project in the Upper San Pedro Sub-watershed and was designed to return cleaned effluent to underground storage in the aquifer, thus protecting future water supplies for the environment and the people who live here. It contains 50 acres of constructed wetlands and 30 acres of water recharge basins.
The major function of the EOP is as a sewage treatment facility, which uses no harmful chemicals and is an all-natural process which currently recharges about 2,700 acre-feet per year to our aquifer (eventual capacity 4,000 af/y). Last but not least it provides habitat for birds and other wildlife. Note: An acre foot of water is approximately an area 200 feet by 200 feet covered by water 1 foot deep
When the EOP was completed in 2002, it was decided to fence it in because of liability issues and the only area open to the public was the bird-viewing platform. However, after the reeds grew up in the wetland ponds it was almost impossible to see anything but the reeds.
In 2003, a group consisting of representatives of the Southeastern Arizona Bird Observatory (SABO), Huachuca Audubon Society (HAS)No longer in existence, and the Friends of the San Pedro River (FSPR) met with city officials and worked out an arrangement whereby trained docents from the three groups would be allowed to take participants inside the fence and walk around the dikes on Sunday mornings. The city required visitors to sign a liability waiver to protect it from legal responsibility and the three groups agreed to provide responsible docents to lead the tours.
There is no need for a reservation. The tours start at the bird-viewing platform where we enter through the locked gate and walk around the cleansing ponds. We usually are back at the parking lot in about two hours. Then we caravan to the Moson Road gate where we enter and walk around the recharge basins. This second section takes about one hour.
The docents who lead the tours not only help to point out and identify birds but they also give information to our visitors about the EOP and its importance to the people of the area. Many of the visitors have expressed gratitude to the city for allowing them the opportunity to see birds that they would otherwise not be able to see. Many have also said they wished their home cities were as advanced as Sierra Vista in its concern for water conservation and the environment.
In September we completed our 16th year of providing docent-led tours at the EOP. All in all, it has been a very successful program and we have taken thousands of tourists and locals around the ponds since we started. Within the confines of the area we have seen bobcats, javelina, deer, coyotes, rabbits, frogs, snakes, raccoons, etc. and, of course, lots of birds. We have recorded 260 species of birds so far.
The treatment ponds are drained, burned, scraped, and refilled periodically, thus the bird activity will vary over time. As the seasons change so do the species of birds. Some come to spend winter with us, some drop in for the breeding season, some use the EOP for a little R&R before continuing their migration, and some stay here all year. Regardless of when you visit you will be treated to a variety of species.
During these sixteen years we have learned that there is little demand for tours in June and July, even though we consistently see 30–50 species on each tour during these months. We have also found that we must start the tours earlier in the warmer months because the birds are more active in early morning and also to beat the heat.
Therefore we start the tours at 7 a.m. from March through October and 8 a.m. from November through February. The number of participants is restricted to 10 per docent and we allow two docents per tour, for a total of 22 people.
There is no charge for these tours but donations are accepted. These donations are/will be used to further enhance the birding experience at the EOP. We have installed picnic tables in the recharge area where we can sit in the shade and update our bird lists (the tables are also available to EOP employees) and we also had a gate installed on Moson Rd. for easier access to the recharge ponds.
Come to the EOP on Sunday morning and take a walk with us. You will be pleasantly surprised by what you will see and learn.