Flood Forecasting: The Significance of River Discharge Forecasts

Floods impact millions of people all over the world, and with flood forecasting taking centre stage, let’s explore how crucial river discharge forecasts are in this context.

Ever since the initial stages of human evolution, rivers have played an integral role in shaping our civilization. Some of the numerous uses include the supply of freshwater for daily consumption, and also contributing to a wide variety of ecosystems. Although, only a small percentage of our planet’s water is concentrated in rivers, more than 50% of drinking water available for human use is supplied by them. In addition, activities like irrigation are highly dependent on the existence of rivers. 

As climatic and environmental changes have a massive impact on humanity and it’s activities, it’s therefore of paramount importance that we understand the dynamics of river flow. One of the most important measures that helps us do exactly that is monitoring river discharge. We will start by exploring more about river discharge, how it’s significance has evolved over time, it’s importance in flood forecast systems, and the connection with water levels. 

Let’s dive in! 

What affects River Flow? 

The most important factor that affects river flow would be climatic variables, since they act as the supply of water to the basins. In addition it can be affected by numerous other factors that can be classified into natural and anthropogenic. For instance, topography and geology are the more natural aspects. On the other hand, human activities like deforestation and dam construction have an impact on water channel alteration. 

Historical perspective

The start of the 20th century marked the installation of numerous discharge-measuring stations in rivers with the aim to monitor river flow variances in the long-run. This was directly linked to managing natural disasters. Eventually, advancements such as the construction of dams required a wider range of data on river flow. Moreover, historical river discharge data allowed attaining a bird’s eye view on climatic and environmental changes.

Did you know? The first regular river discharge measurements in Europe began in the 1880s.

Current Practices and Initiatives

Many gauging stations are still in operation today thanks to entities like the United States Geological Survey (USGS) and the National River Flow Archive in the United Kingdom. For context, The USGS offers real-time hydrological data for various water-related projects and also flood forecasting. This further highlights the significance of river discharge data. 

Are River Discharge forecasts important in the context of Flood forecasting?

Yes!! To understand the context better, let’s consider this from a global scale.

The Copernicus Emergency Management Service (CEMS) of the European Commission is home to GloFAS, an international flood service that monitors and forecasts floods on a global scare. It’s functioning is based on river discharge exceeding pre-defined flood thresholds. The main variable for their flood forecasting system is the river discharge data over 24 hours. 

Even neural network models like Long Short-Term Memory (LSTM) for flood forecasting depend on daily discharge data. According to one of the studies conducted on this model based on the Da river basin in Vietnam, this turned out to be a viable option thanks to it’s high accuracy. The dependency on discharge data was equally relevant when it came to hydrological models based on basins like Amazon and Congo. 

Link between Water levels and Discharge

In the delicate balance of hydrological systems, the synergy between river discharge and water level forecasts has an important role. They are powerful tools for water authorities when it comes to efficient flood forecasting and addressing other natural disasters. 

Water authorities can proactively implement measures to diminish the impact of rising water levels and minimize the risk to infrastructure and people by making use of river discharge data. Why? River discharge is a basic factor that affects water levels.

Variations in river discharge impact water levels downstream. Consequently, Water authorities can address floods more efficiently by analyzing these patterns. 

According to the quasi distribution model, the connection between water level and the corresponding discharge at a location can be signified by a power equation of the type  Q = c*(G-G0)^b  where b, c are constants. Whereas, Q is discharge and G, G0 represent the water levels. Therefore, discharge and water levels are closed interrelated!

To sum it up

In conclusion, river discharge forecasts are a crucial tool for water authorities when it comes to flood forecasting. By making use of the vast amount of data available, mathematical modeling, and advanced technology, we can address hydrological issues with efficiency. 

We at BWI are proud to be offering river discharge forecasts that could potentially aid millions of people! 

The increasing significance of river discharge for flood forecasting
River discharge data is becoming increasingly relevant in the context of addressing flooding


  1. https://nwa.mah.nic.in/Dl_modules/FFT_module/index.htm
  2. Flood forecasting Manual (1989), Central Water Commission, New Delhi.
  3. Le, X.-H., Ho, H. V., Lee, G., Jung, S. Application of Long Short-Term Memory (LSTM) Neural Network for Flood Forecasting. https://www.mdpi.com/2073-4441/11/7/1387
  4. Flood Forecasting: A global perspective. https://www.sciencedirect.com/topics/earth-and-planetary-sciences/flood-forecasting
  5. Harrigan.S, Zsoter, E., Cloke, H., Salamon, P., Prudhomme, C. Daily ensemble river discharge reforecasts and real-time forecasts from the operational Global Flood Awareness System. Hydrology and Earth System Sciences https://hess.copernicus.org/articles/27/1/2023/
  6. Depetris, P. J. The Importance of Monitoring River Water Discharge. Frontiers in Water, https://www.frontiersin.org/journals/water/articles/10.3389/frwa.2021.745912/full
  7. Anderson, M. G., & McDonnell, J. J. (Eds.). (2005). Encyclopedia of Hydrological Sciences, Vol. 5. Chichester: Wiley and Sons.
  8. Dai, A., Qian, T., Trenberth, K. E., Milliman, J. D. (2009). Changes in continental freshwater discharge from 1948 to 2004.