Oatka Creek ( ) is the third longest tributary of the Genesee River, located entirely in the Western New York region of the U.S. state of New York. From southern Wyoming County, it flows to the Genesee near Scottsville, draining an area of that includes all or part of 23 towns and villages in Wyoming, Genesee, Livingston and Monroe counties as well. Its name means "leaving the highlands" or "approaching an opening" in Seneca.
Like its parent stream it originated during the end of the last Ice Age, as glacial impact on the upper Allegheny Plateau created a rolling landscape streams could gradually erode through, The Oatka carved a deep groove known today as the Oatka Valley, where the upper creek's two major settlements would be established. Native Americans of the Seneca nation established a few settlements along it where clearings arose in the forest. The Revolutionary War's Sullivan Expedition brought the valley's fertile soil to the attention of the emerging nation, and the region was opened for settlement shortly after the war.
For a time the Oatka was called Allan's Creek after the area's first settler, Ebenezer "Indian" Allan. Its waterpower facilitated early 19th-century European settlement of the abundant fertile lands in the Holland Purchase. Today it remains an important regional resource, used for water supply and recreational purposes, and actively protected to assure water quality. It is a popular trout stream, stocked from the oldest fish hatchery in the Western Hemisphere near its mouth. A dam in Le Roy makes the section below it a losing stream, dry during the warm months of the year as the stream flows through subterranean channels.
Course Several small streams, some of which ultimately rise to the north at elevations of almost , come together to create the main stem of the creek amid the fields and woodlots on the high plateau in Gainesville just south of the Warsaw town line, a short distance west of Silver Spring Road. The new stream flows first south a mile, then turns northwest paralleling the Norfolk Southern railroad tracks toward the small hamlet of Rock Glen. There it crosses for the first time New York State Route 19 (NY 19), which it will parallel closely for much of the rest of its length.
To the west of Rock Glen, it passes through the narrow gorge that gave it its name, emerging at another hamlet, Newburg, at the head of the Oatka Valley it follows for the rest of its run. Again crossing under Route 19, it has descended since its rise. From Newburg it meanders northwest, then north, staying close to the highway on the valley floor.
Several miles further downstream it enters Warsaw, the county seat. It goes under Route 19 again and trends to the west, flowing under U.S. Route 20A to pass to the west of Warsaw High School and its athletic fields. North of the village the valley widens, staying generally level. The creek and NY 19 cross again amid large cultivated fields.
The valley begins to angle northeasterly towards Wyoming, which the Oatka bypasses to the southeast into a large wooded area. It then passes through the largest wetlands along it course. North of that it crosses Route 19 again as that road turns eastward briefly. The two return to each other when they cross into Genesee County at Pavilion, where NY 63 crosses as they resume a northward heading, and there is another significant wetlands area.
In another small wood two miles (3.2 km) north of Pavilion, US 20 crosses. The creek bends west, reaching its greatest distance from Route 19, then north-northeast back to the highway's vicinity. It enters the village of Le Roy on a northeast course, crossing Route 19 again as it widens into a reservoir behind the dam just south of NY 5.
It narrows again north of the village towards Buttermilk Falls and the section that flows underground in warm, dry weather. The valley here is broad, its walls now long and gently sloped instead of steep and short. After going over the falls, marking the Onondaga Escarpment, it turns east, leaving NY 19 a mile south of the New York State Thruway. This geologically distinct section is known as the lower Oatka. It dips south, north and then south again through a largely wooded area as it approaches Genesee Country Village and enters Monroe County near Mumford.
After bypassing that hamlet to the north, NY 383 parallels on the north and the CSX rail line across New York on the south, as the creek reaches Oatka Creek Park, a large tract of former farmland to its south. Here both road and rail are to the north of the stream, widening again. Beyond the park it enters an area of predominantly farmland again as it passes south of Scottsville, where NY 251 enters the village by bridging the Oatka. A mile further along, it empties into the Genesee.
Watershed
The Oatka's basin is relatively narrow and does not extend far from the Oatka Valley or the towns through which the creek itself flows. Almost all of the towns of Warsaw, Pavilion and Le Roy are within the watershed, along with large portions of Covington, Gainesville, Middlebury and Wheatland. Most of the eastern half of Stafford is in the Oatka basin even though only a small portion of the creek flows through it.
In Livingston County Caledonia is the only town with land in the watershed, consisting mostly of its northeastern corner and most of the village of Caledonia. Other towns with no portions of the creek itself having large sections within its basin are Perry, Orangeville, and Bethany. Small portions of Castile, Wethersfield, Byron and Bergen also drain into the Oatka.
There are five villages wholly or partially within the watershed. The former are Warsaw, Wyoming and Le Roy. Closer to its mouth are Scottsville and Caledonia. These are the only concentrated areas of development and population within it. The majority (73%) of the watershed is active or inactive agricultural land. Forests cover another 21%. Most of the remainder is residential or commercial land, with industrial use accounting for just 1%.Tatakis, Timothy; ; Oatka Creek Watershed Committee; 31. Retrieved October 13, 2010.
The watershed's highest point of is located in southeastern Orangeville; its lowest point, , is the Oatka's mouth. Including the Oatka itself, there are of stream in the watershed.
There are few significant lakes or ponds within the watershed. The largest is Lake Le Roy, near the headwaters of Mud Creek in Pavilion. It is a reservoir that once served as the main water supply for the village of Le Roy.State of the Basin, 32. The only protected area in the Oatka watershed besides Oatka Creek Park is the Carlton Hill Wildlife Management Area in Middlebury, north of Warsaw.
Water quality The United States Geological Survey maintains two stream gauges on the creek, at Garbutt near the mouth and Warsaw below its headwaters. Average annual streamflow is at the upstream station and downstream. Flow at Warsaw averages 21–36% of what it is at Garbutt, but is much higher downstream in springtime and after significant runoff events.State of the Basin, 16.
Only one community along the creek, the village of Warsaw, uses it as a water supply, putting it through a filtration plant before distributing it to residents and other customers. Its wastewater treatment plant is downstream of the intake. Le Roy also has state permits to discharge effluent into the stream from their wastewater plants, along with the Lapp Insulators plant in Le Roy and the fish hatchery in Caledonia (via the Spring Creek tributary). The latter has the highest permitted discharge of any permit in the Oatka watershed.State of the Basin, 34. The villages of Caledonia and Wyoming, and one of Pavilion's water districts, use wells in the watershed.
The creek's water quality has been extensively studied in its lower watershed, below Buttermilk Falls. Most chemicals within it are within normal limits, with slightly higher levels of sulfates due to the gypsum and dolomite present in the bedrock. Those minerals also produce detectable magnesium and strontium levels as well. Trichloroethylene is sometimes found as well, the legacy of a spill from a railroad accident near Le Roy in the early 1970s. During high-runoff events, fecal coliform in the lower Oatka sometimes exceeds permitted levels.State of the Basin, 20–27.
There are no major issues at present that could significantly degrade water quality on most of the stream. Accordingly, the state's Department of Environmental Conservation (DEC) classifies the Monroe and Genesee sections of the stream as "threatened", since some issues could arise in the future. The Wyoming County portion is considered "stressed", in that while its quality is generally good, occasional issues arise that limit use.State of the Basin, 13.
In 1999, following a "Caring for Creeks" conference in Rochester, the Oatka Creek Watershed Committee was formed. It sponsored research into the stream and watershed, including the first "State of the Basin" report two years later. Intermunicipal agreements were adopted in 2004, and an outline for an Oatka Creek Watershed Management Plan was adopted in 2006, in cooperation with the Genesee/Finger Lakes Regional Planning Council.
Wildlife There is limited data on the fish and plant species that thrive in and around the creek as no comprehensive survey has been done. The state has identified several communities of species it lists as rare, threatened or endangered. To protect them more effectively it has limited publication of the exact species or location of the communities.State of the Basin, 12.
More specific data exists on benthic macroinvertebrates, or larger organisms that depend on the sediment on the stream floor. These are primarily the immature forms of insects that live on land as adults. Many of these species, such as caddisflies and stoneflies, are pollution-intolerant and thus their presence is an indicator of good water quality. They were found during a 1989–90 survey of the lower Oatka, but in lower numbers than expected. The stream is thus considered "slightly impacted" by pollution.State of the Basin, 27–28.
Many of those insects constitute the food supply for various trout species. The lower Oatka is considered a blue-ribbon brown trout fishery, with some brook trout populating the water as well. The state fish hatchery on Spring Creek near Caledonia stocks the stream annually, and there is also evidence of a wild trout fishery on the stretch between Bowerman and Wheatland Center roads. A 1999 survey estimated the creek's total trout biomass at 30 pounds per acre (33 kg per hectare) bass, walleye and northern pike have also been taken near the Genesee.
Geology Buttermilk Falls divides Oatka Creek into two distinct geological regions. The upper stream's bedrock is local sedimentary rock formations, with the shales and sandstones of the Sonyea Group, shale-limestone Genesee Group and Tully Limestone dominating from the headwaters to Pavilion. Between there and Le Roy the shales and thin limestones of the Hamilton Group underlie the creek.Dowling, C.B. et al; ; Oatka Creek Watershed Committee, December 2001, 12. Retrieved October 15, 2010.
North of Le Roy, the Oatka becomes a losing stream, with water disappearing into the ground. In the warmer months this results in the creekbed drying up above Buttermilk Falls, and slowly re-emerging further down from springs and seeps.Geochemistry, 11. After it does, and turns to the east, it flows over the Akron Formation, Bertie Group of dolomitic shales, and the Salina Group. The latter is diverse, including evaporites such as halite and gypsum in addition to its limestones and shales.