| Place Name | Grand River Township (Decatur County) |
| Place Type | Township |
| ZIP Code(s) | 50108 50133 50140 |
| County | Decatur County |
| Area Code(s) | 641 |
| Timezone | Central Daylight Time (CDT) |
| Population (2021) | 31 |
| Majority Ethnicity | White 100% |
| US Congressional District(s) | Iowa 2nd |
| State House Districts | 27 |
| State Senate Districts | 14 |
| Race/Ethnicy | Percentage of Population (2021) |
|---|---|
| White | 100% |
| African American | 0% |
| Hispanic | 0% |
| Asian | 0% |
| Native American | 0% |
| Hawaiin/Pacific Islander | 0% |