# Introduction to DEA Waterbodies ¶

• **Sign up to the DEA Sandbox** to run this notebook interactively from a browser

• Compatibility: Notebook currently compatible with both the NCI and DEA Sandbox environments

• Products used: DEA Waterbodies

## Background¶

It is important to have up-to-date information about the extent and location of surface water in Australia. It provides us with a common understanding of this valuable and increasingly scarce resource.

### What this product offers¶

DEA Waterbodies uses Geoscience Australia’s archive of over 30 years of Landsat satellite imagery to identify where almost 300,000 waterbodies are in the Australian landscape and tells us the wet surface area within those waterbodies.

The tool uses a water classification for every available Landsat satellite image and maps the locations of waterbodies across Australia. It provides a time series of wet surface area for waterbodies that are present more than 10% of the time and are larger than 3125 m$$^2$$ (5 Landsat pixels).

The tool indicates changes in the wet surface area of waterbodies. This can be used to identify when waterbodies are increasing or decreasing in wet surface area.

Disclaimer: DEA Waterbody graphs show the wet surface area of waterbodies as estimated from satellites. They do not show depth, volume, purpose of the waterbody, nor the source of the water.

The product contains polygons of maximum extent and surface area time series for each waterbody. These waterbodies have been derived from Water Observations from Space, a classifier which detects open water in Landsat pixels.

### Applications¶

• Understand and manage water across Australia

• Gain insights into the severity and spatial distribution of drought

• Identify potential water sources for aerial firefighting during bushfires

### Publications¶

• Krause, C. et al. (in preparation)

• Mueller, N., Lewis, A., Roberts, D., Ring, S., Melrose, R., Sixsmith, J., Lymburner, L., McIntyre, A., Tan, P., Curnow, S., & Ip, A. (2016). Water observations from space: Mapping surface water from 25 years of Landsat imagery across Australia. Remote Sensing of Environment, 174, 341–352. https://doi.org/10.1016/j.rse.2015.11.003

Note: For more technical information about DEA Waterbodies, visit the official Geoscience Australia DEA Waterbodies product description.

## Description¶

This notebook will demonstrate how to load data from DEA Waterbodies using the scripts in this repository. Topics covered include:

1. Getting a list of available polygons in an area

2. Accessing a polygon

3. Plotting the surface area of the polygon over time

## Getting started¶

To run this analysis, run all the cells in the notebook, starting with the “Load packages” cell.

Import Python packages that are used for the analysis.

[1]:

import sys
import matplotlib.pyplot as plt

sys.path.append("../Scripts")
from dea_plotting import display_map
import dea_waterbodies


## Analysis parameters¶

Choose an area to analyse:

[2]:

xlim = (149.05, 149.19)
ylim = (-35.21, -35.33)

# Preview area on a map
display_map(xlim, ylim)

[2]:


## Getting data¶

Every waterbody in DEA Waterbodies has a unique identifier called a *geohash*. The geohash of a waterbody is derived from their position, and this process can be reversed to obtain the location from the geohash. You can also get the geohash for a waterbody from DEA Maps by clicking on a waterbody. It’s the “waterbody identifier” in this screenshot: