# USGS Water Services parameter-codes API

**Canonical:** https://apis.io/apis/usgs-water/usgs-water-parameter-codes-api/  
**Provider:** USGS Water Services — https://apis.io/providers/usgs-water/  
**Base URL:** https://waterservices.usgs.gov/nwis/iv/  
**Documentation:** https://waterservices.usgs.gov/docs/instantaneous-values/instantaneous-values-details/

USGS Water Services parameter-codes API is one of 43 APIs that [USGS Water Services](https://apis.io/providers/usgs-water/) publishes on the [APIs.io](https://apis.io/) network, described by a machine-readable OpenAPI specification. Tagged areas include parameter-codes. The published artifact set on APIs.io includes an OpenAPI specification and API documentation.

Parameter codes are 5-digit codes and associated descriptions used to identify the constituent measured and the units of measure. Some parameter code definitions include information about the sampling matrix, fraction, and methods used to measure the constituent. Some parameters are fixed-value (fxd) numeric codes having textual meaning (for example: parameter code 00041 is a weather code parameter, code of 60 means rain), but more commonly represent a numeric value for chemical, physical, or biological data.

## Machine-readable artifacts (3)

- **OpenAPI** — https://raw.githubusercontent.com/api-evangelist/usgs-water/refs/heads/main/openapi/usgs-water-parameter-codes-api-openapi.yml
- **Documentation** — https://api.waterdata.usgs.gov/docs/
- **Website** — https://api.waterdata.usgs.gov/

## Other USGS Water Services APIs (12)

- [USGS Instantaneous Values Service](https://apis.io/apis/usgs-water/instantaneous-values/)
- [USGS Daily Values Service](https://apis.io/apis/usgs-water/daily-values/)
- [USGS Site Service](https://apis.io/apis/usgs-water/site-service/)
- [USGS Statistics Service](https://apis.io/apis/usgs-water/statistics-service/)
- [USGS Groundwater Levels Service](https://apis.io/apis/usgs-water/groundwater-levels/)
- [Water Quality Portal (WQP) API](https://apis.io/apis/usgs-water/water-quality-portal/)
- [USGS Water Data Statistics API](https://apis.io/apis/usgs-water/statistics-next-gen/)
- [USGS Water Services agency-codes API](https://apis.io/apis/usgs-water/usgs-water-agency-codes-api/)
- [USGS Water Services altitude-datums API](https://apis.io/apis/usgs-water/usgs-water-altitude-datums-api/)
- [USGS Water Services aquifer-codes API](https://apis.io/apis/usgs-water/usgs-water-aquifer-codes-api/)
- [USGS Water Services aquifer-types API](https://apis.io/apis/usgs-water/usgs-water-aquifer-types-api/)
- [USGS Water Services channel-measurements API](https://apis.io/apis/usgs-water/usgs-water-channel-measurements-api/)

## Tags

parameter-codes

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/usgs-water/usgs-water-parameter-codes-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/usgs-water/.