The Lower Mississippi watershed (HUC-2 region 08) encompasses the lower Mississippi River from Missouri to the Gulf of Mexico, draining through one of the most economically vital river corridors in the US. Covering 106,579 sq mi across 7 states and provinces, it is one of the 18 major drainage regions of the contiguous United States.
Use the interactive Lower Mississippi watershed map below to explore all 9 HUC-4 sub-regions within the basin. Click any sub-region for its code, name, and area. Or view the interactive US watershed map to see all 18 major basins side by side.
Major Drainage Basins
Lower Mississippi Watershed by the Numbers
- HUC-2 code: 08
- Total area: 106,579 sq mi
- States and provinces: AR, IL, KY, LA, MO, MS, TN
- HUC-4 sub-regions: 9
HUC-4 Sub-regions of the Lower Mississippi Watershed
The USGS Watershed Boundary Dataset divides the Lower Mississippi region into 9 HUC-4 sub-regions. Each sub-region drains into a distinct river system or coastal outlet within the larger basin:
| HUC-4 Code | Sub-region Name | Area (sq mi) |
|---|---|---|
| 0801 | Lower Mississippi-Hatchie | 11,762 |
| 0802 | Lower Mississippi-St. Francis | 16,175 |
| 0803 | Lower Mississippi-Yazoo | 14,052 |
| 0804 | Lower Red-Ouachita | 20,508 |
| 0805 | Boeuf-Tensas | 5,295 |
| 0806 | Lower Mississippi-Big Black | 7,078 |
| 0807 | Lower Mississippi-Lake Maurepas | 5,820 |
| 0808 | Louisiana Coastal | 14,598 |
| 0809 | Lower Mississippi | 11,290 |
States and Provinces in the Lower Mississippi Watershed
The Lower Mississippi watershed spans 7 states and provinces: AR, IL, KY, LA, MO, MS, TN. Water falling anywhere within these boundaries ultimately drains through the Lower Mississippi basin’s river network.
Frequently Asked Questions
What is the Lower Mississippi watershed?
The Lower Mississippi watershed is HUC-2 region 08 of the US Watershed Boundary Dataset. It encompasses the lower Mississippi River from Missouri to the Gulf of Mexico, draining through one of the most economically vital river corridors in the US, covering 106,579 sq mi across AR, IL, KY, LA, MO, MS, TN.
How large is the Lower Mississippi watershed?
The Lower Mississippi watershed covers 106,579 square miles, making it one of the 18 major drainage regions of the contiguous United States.
How many sub-regions does the Lower Mississippi watershed have?
The Lower Mississippi watershed contains 9 HUC-4 sub-regions as defined by the USGS Watershed Boundary Dataset.
→ View all 18 major US watershed basins on the national interactive map
