> For the complete documentation index, see [llms.txt](https://swatplus.gitbook.io/io-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://swatplus.gitbook.io/io-docs/swat+-output-files/aquifer.md).

# Aquifer

The printing of aquifer output is controlled by entering "y" or "n" in the *aquifer* line in [print.prt](/io-docs/introduction-1/simulation-settings/print.prt.md). In addition, a basin average of all aquifers can be printed by entering "y" in the *basin\_aqu* line in [print.prt](/io-docs/introduction-1/simulation-settings/print.prt.md). Aquifer output can be printed at daily, monthly, yearly, and average annual time steps. The names of the aquifer output files are as follows: 

* aquifer\_day.txt
* aquifer\_mon.txt
* aquifer\_yr.txt
* aquifer\_aa.txt
* basin\_aqu\_day.txt
* basin\_aqu\_mon.txt
* basin\_aqu\_yr.txt
* basin\_aqu\_aa.txt

| Field    | Description                                       | Unit    |
| -------- | ------------------------------------------------- | ------- |
| jday     | Julian Day                                        | n/a     |
| mon      | Month                                             | n/a     |
| day      | Day of the month                                  | n/a     |
| yr       | Year                                              | n/a     |
| unit     | ID of the object                                  | n/a     |
| gis\_id  | Object ID in GIS                                  | n/a     |
| name     | Name of the object or SWAT+ setup (basin outputs) | n/a     |
| flo      | Groundwater flow                                  | mm      |
| dep\_wt  | Depth from surface to aquifer water table         | m       |
| stor     | Aquifer storage                                   | mm      |
| rchrg    | Aquifer recharge                                  | mm      |
| seep     | Seepage out of the aquifer                        | mm      |
| revap    | Revap from the aquifer                            | mm      |
| no3\_st  |                                                   | kg N/ha |
| minp     | Mineral phosphorus in the groundwater             | kg      |
| orgn     | Organic nitrogen in the groundwater               | kg N/ha |
| orgp     | Organic phosphorus in the groundwater             | kg P/ha |
| rchrgn   |                                                   | kg N/ha |
| nloss    | Nitrogen losses in the aquifer                    | kg N/ha |
| no3gw    |                                                   | kg N/ha |
| seepno3  |                                                   | kg      |
| flo\_cha | Groundwater flow to channels                      | mm      |
| flo\_res | Groundwater flow to reservoirs                    | mm      |
| flo\_ls  | Groundwater flow to other aquifers                | mm      |