Peterson Ditch
Peterson Ditch drains agricultural and residential land south of the lake and enters Winona on the southwest side.
Winona Lake is part of a much larger drainage area. Rain falling on fields, roads, yards and ditches throughout the watershed can eventually reach the lake.
Explore the watershed
The coral boundary shows the federal Winona Lake–Eagle Creek subwatershed. Blue lines show the main streams and ditches; blue shapes show the lakes.
Watershed boundary
Principal streams & ditches
Lakes
How water reaches the lake
Four named ditch systems carry water toward Winona Lake. Eagle Creek carries water out.
Evans Ditch
Federal records label this Keefer–Evans Ditch. It flows north through Lake John before reaching Winona Lake.
Wyland Ditch
Wyland Ditch connects Sharon, Sheely and Wyland lakes to Winona Lake.
Tennant Ditch
Tennant Ditch crosses the southeast part of the watershed near Tennant and Sellers lakes.
The outlet
Eagle Creek
Winona Lake drains west through Eagle Creek. The water continues to Walnut Creek, then the Tippecanoe River.
Winona Lake→Eagle Creek→Walnut Creek→Tippecanoe River
Rain does not have to fall directly on Winona Lake to affect it. Stormwater from miles away can carry soil and nutrients through these waterways and into the lake.
Fourteen lakes in the watershed
The Lilly Center’s watershed map identifies 14 lakes. Winona is the largest and lies farthest downstream.
Winona LakeSheely LakeWyland Lake
Stevens LakeReed LakeMcPherson Lake
Stafford LakeSherburn LakeSellers Lake
Tennant LakeLaspew (Larrew) LakeLake John
Sharon LakeHorseshoe Lake
What runoff can carry
As rainwater moves downhill, it can pick up soil, nutrients, bacteria, oil, salt and fertilizer.
Soil & nutrients
Eroded soil can carry phosphorus into streams. In the lake, that nutrient can feed algae growth.
Waste & bacteria
Pet waste, livestock waste and failing septic systems can move bacteria downstream after rain.
Streets & lawns
Oil, road salt, grass clippings and excess fertilizer can wash into storm drains and ditches.
Ways to reduce runoff pollution: keep leaves and grass out of drains, use phosphorus-free fertilizer, pick up pet waste, stabilize bare soil and plant native vegetation near ditches and shorelines.
How this was mapped
The boundary comes from the U.S. Geological Survey and USDA Watershed Boundary Dataset: HUC-12 051201060203, “Winona Lake–Eagle Creek.” Stream and lake shapes come from the USGS National Hydrography Dataset and were checked against the Lilly Center’s local watershed map. Federal records divide some ditches into separate field segments, so this map connects gaps between the named Peterson, Evans, Wyland and Tennant ditches. Peterson Ditch’s eastern branch follows the local streambank-assessment map.
The 18,730-acre figure comes from the Lilly Center for Lakes & Streams. The federal HUC polygon covers 20,554 acres. The two sources use different boundaries and measurement methods, so both figures are included here.
| Boundary | USGS/USDA Watershed Boundary Dataset, HUC-12 051201060203 |
| Streams & lakes | USGS National Hydrography Dataset, accessed July 2026; Peterson eastern branch reconciled to the local streambank-assessment map |
| Local watershed facts | Lilly Center for Lakes & Streams, Winona Lake profile and watershed map |
| Map detail | Geometry simplified to approximately 10–20 feet for fast drawing; not a property or drainage survey |
Watershed resources
Live inlet & outlet monitor →Watch flow, depth, velocity and temperature change after rain.
Lilly Center lake profile →Research, water-quality reports and the original watershed map.
Peterson Ditch project →See how local partners are keeping sediment from reaching Winona.
The 200-Foot Lap →Explore the idle-speed line and Winona’s deep-water area.