The Green River WTP (waste water treatment ponds) are located on the south side of town, and accessed via Silliman Lane. There are actually 4 ponds on the location, with the largest one being the northwest pond visible form Silliman Lane covering 12.7 acres. The northeast pond is the second largest at 7.3 acres, while the southeast pond covers 4 acres, and the southwest just 3.7 acres. Since only the northwest pond is visible from Silliman Lane the others are much harder to find access to. Although you can view all the ponds from the west bound lanes of I-70, this is a dangerous area to scan from as there are no pullouts. At the end of Silliman Lane a dirt road continues through a fence and actually wraps all the way around the south end, possibly giving view to the other ponds. I am not sure of whether or not this is private property or who to contact for access. To the south of the ponds are barren desert slopes and then the interstate. The north and west sides are bordered by farms, while the east side is bordered by the Green River. Like waste water treatment ponds through rural Utah, these provide some of the best birding in Green River, and are the only still water in the area making them a haven for waterbirds of any kind--especially during migration.
Most visits to this location are during the spring and fall when birders are headed between the southeaster part of Utah and the Wasatch Front. The WTP is a must stop if you pass through as there will invariably be something unexpected for the location in the middle of the desert. In the spring as waterfowl migrants head north you can make a pretty good list here with a short stop. While GADWALL, NORTHERN SHOVELER, and CINNAMON TEAL are present in good numbers you might also find AMERICAN WIGEON, BLUE-WINGED TEAL, REDHEAD, and LESSER SCAUP. A hybrid MALLARD x GADWALL (Brewer's Duck), was seen her in April 2015. Although some divers like PIED-BILLED GREBE and DOUBLE-CRESTED CORMORANT have been observed they aren't as expected. WHITE-FACED IBIS may be here, or along the river, or in the fields along Silliman Lane. Perhaps the biggest draw for birders is shorebirds. With the Green River being a natural north-south migration route--the standing water here provides excellent feeding grounds. LESSER YELLOWLEGS, MARBLED GODWIT, LONG-BILLED DOWITCHER, LEAST SANDPIPER, SPOTTED SANDPIPER, and WILSON'S PHALAROPE have been seen here. 4 species of Gulls have also been recorded--with large flocks of FRANKLIN'S GULLS using the ponds during migration, and BONAPARTE'S GULLS popping up mixed in. All 6 species of regularly occurring swallows show up here during migration, while species like WESTERN KINGBIRD, SAY'S PHOEBE, ASH-THROATED FLYCATCHER, and NORTHERN MOCKINGBIRD are reported form the summer months. GRAY CATBIRD are occasionally reported, as well as BLUE GROSBEAK, YELLOW-BREASTED CHAT, and BULLOCK'S ORIOLE. Most of these passerine species are more likely to occur along Silliman Lane to the north and are likely from earlier checklists before this location was created. Needless to say the entire area is a migrant trap for lots of species. With enough birders stopping to check the ponds out on a regular basis some big finds would come form here in the desert where standing water is at a premium.
From the intersection of SR-19 and Broadway in Green River, head south on Broadway for .2 miles. Turn left on to Green River Avenue for .3 miles. Turn right onto Airport Road for .2 miles. Here there will be a left turn onto Silliman Lane. The lane continues for .7 miles to the Green River WTP.