Reservoir · South Dakota · United States · USACE CWMS
Deerfield Reservoir
91.3% full
Capacity
19.31 hm³
Volume stored
18 hm³
Coordinates
44.029°N, 103.786°W
Last updated
2026-08-13
Current fill
91.3%vs 7 days ago
-0.4%losing
vs 1 year ago
-2.8%year-over-year
7-day trend
→stable
Data source: USACE CWMS — US Army Corps of Engineers — daily reservoir storage volume. Capacity is the design (normal full-pool) capacity from the US National Inventory of Dams (NID); fill % = current volume ÷ design capacity. Last reading: 2026-08-13.
Catchment Weather
Past 30 days + 14-day forecast · Open-Meteo
Satellite imagery: Esri, Maxar, Earthstar Geographics. Map: Esri, HERE, Garmin, © OpenStreetMap contributors. 44.029, -103.786 · Open in Google Maps
About Deerfield Reservoir
As of August 13, 2026, Deerfield Reservoir is filled to 91.3% of its total capacity, holding roughly 18 hm³ of water out of a maximum 19 hm³. At this level the reservoir is high.
Over the most recent week on record the fill level has held broadly steady (-0.4 pts), and it is 2.8 points below its level on the same date a year earlier.
Across the readings we hold for Deerfield Reservoir — 1817 data points between August 15, 2021 and August 13, 2026 — the level has ranged from a low of 87.4% (July 11, 2025) to a high of 101.8% (July 2, 2023). On average the reservoir is fullest around June and at its lowest around October.
It is operated by USACE primarily for multiple purposes. It lies within the South Dakota basin at 44.029°N, 103.786°W.
Key facts
- Current fill level
- 91.3%
- Water stored
- 18 hm³
- Total capacity
- 19 hm³
- 7-day change
- ▼ 0.4 pts
- Year-on-year
- ▼ 2.8 pts
- Primary use
- Multipurpose
- River basin
- South Dakota
- Operator
- USACE
- Coordinates
- 44.029°N, 103.786°W
- Last updated
- August 13, 2026
Recent readings
| Date | Fill level | Volume (hm³) |
|---|---|---|
| 13 Aug 2026 | 91.3% | 18 |
| 12 Aug 2026 | 91.3% | 18 |
| 11 Aug 2026 | 91.3% | 18 |
| 10 Aug 2026 | 91.4% | 18 |
| 9 Aug 2026 | 91.5% | 18 |
| 8 Aug 2026 | 91.5% | 18 |
| 7 Aug 2026 | 91.6% | 18 |
| 6 Aug 2026 | 91.7% | 18 |
| 5 Aug 2026 | 91.8% | 18 |
| 4 Aug 2026 | 91.8% | 18 |
| 3 Aug 2026 | 91.9% | 18 |
| 2 Aug 2026 | 92.0% | 18 |
Frequently asked questions
What is the current water level of Deerfield Reservoir?
As of August 13, 2026, Deerfield Reservoir is at 91.3% of its capacity, holding approximately 18 hm³ of water, according to USACE CWMS (US Army Corps of Engineers) data.
Is Deerfield Reservoir reservoir full?
No. As of August 13, 2026, Deerfield Reservoir is high at 91.3% of its capacity, so it is not full.
Is the water level at Deerfield Reservoir rising or falling?
The level at Deerfield Reservoir has been broadly stable over the latest week on record (-0.4 points).
How much water can Deerfield Reservoir hold?
Deerfield Reservoir has a total capacity of 19 hm³.
Where is Deerfield Reservoir reservoir located?
Deerfield Reservoir is located in South Dakota, United States, within the South Dakota basin (coordinates 44.029°N, 103.786°W).
What is Deerfield Reservoir used for?
Deerfield Reservoir is used primarily for multiple purposes, and is managed by USACE.