Flooding poses a significant threat to both rural and urban areas in South Africa, with devastating consequences for communities, infrastructure, and the economy. From 1981 to 2023, numerous floods were reported across the country, yet many events, especially in urban areas, were either underreported or not recorded with sufficient detail for further analysis or prediction work.

Traditional flood monitoring systems often rely on hydrological models that can miss localised events, especially in densely populated areas where infrastructure and topography can create microclimates. The challenge lies in accurately identifying the exact timing (to the day) and location of past floods using historical data, key to creating a comprehensive flood archive that can inform disaster preparedness and mitigation efforts.The goal of this challenge is to develop a machine learning model capable of identifying the specific day in which an urban flash flood occurred, based on aggregated historical CHIRPS daily precipitation data and a composite earth observation image of the area.

You will work with a dataset that includes reported flood locations from 1981 to 2023 in South Africa, with CHIRPS data aggregated within a 5km radius of each reported flood point.

In this challenge, you must determine the precise date a flood occurred and distinguish between time series with and without flood events. By successfully predicting the day a flood occurred, the model will contribute to building a complete historical catalogue of urban floods across South Africa. This catalogue will be implemented by the South African Environmental Observation Network (SAEON), providing critical data to identify previously missed flood events and to improve future flood forecasting and response strategies.

By creating a detailed archive of past urban floods, SAEON will have access to a powerful tool for analysing flood patterns, understanding the impact of urbanisation on flooding, and identifying vulnerable areas that may be at higher risk in the future. This archive can be used to improve early warning systems, optimise resource allocation during emergencies, and inform urban planning to reduce flood risk.

About Google DeepMind (deepmind.google)

Google DeepMind is a world-leading AI research lab with British heritage and an international team, committed to building AI responsibly, delivering scientific breakthroughs, and creating products that improve billions of lives. The unit’s breakthroughs over the last decade include AlphaGo - the first computer program to defeat a Go world champion, Transformers - neural networks that underpin all modern language models, AlphaFold - an AI system that predicts 3D models of protein structures enabling further scientific advancement, and Gemini, a family of versatile AI models built from the ground up for multimodality, seamlessly combining and understanding text, code, images, audio and video.

About South African Environmental Observation Network (SAEON) and South African Risk and Vulnerability Atlas (SARVA) (saeon.ac.za)

The South African Environmental Observation Network (SAEON) is a long-term environmental observation and research facility of the National Research Foundation (NRF). Its three focus areas are environmental observation, data management, and education outreach. SAEON has a distributed network of seven nodes and two research infrastructures. The research network covers the major terrestrial and marine ecosystems in South Africa. The South African Risk and Vulnerability Atlas (SARVA) is hosted within SAEON's data management node, uLwazi. SARVA is an initiative of the Department of Science and Innovation Global Change Grand Challenge. The objective of SARVA is to profile the vulnerability of local municipalities and proactively strengthen the ability of the people of South Africa to cope with a range of natural and anthropogenic hazards (including climate change, biodiversity loss, and epidemics). SARVA achieves these objectives by providing open access to decision-ready data and translating the data and risk maps into digestible narratives for decision-makers using innovative decision-support tools, including indicator dashboards, infographics, and a searchable atlas.

The evaluation metric for this challenge is Log Loss.

Your submission should look like:

ID                    Target
id_j7b6sokflo4k_X_0   0.73     
id_j7b6sokflo4k_X_1   0.03     

The values can be between 0 and 1. Do not set thresholds (or round your probabilities) to improve your place on the leaderboard. In order to ensure that the client receives the best solution Zindi will need the raw probabilities. This will allow the clients to set thresholds to their own needs.

🥇 1st Place: @Tomek_

🥈 2nd Place: Team Central Park

🥉 3rd Place: @3B

1st prize: $5 000 USD

2nd prize: $3 000 USD

3rd prize: $2 000 USD

If your solution places 1st, 2nd, or 3rd on the final leaderboard, you will be required to submit your winning solution code to us for verification, and you thereby agree to share your solution under a CC-BY SA 4.0 license.

There are 10 000 Zindi points available. You can read more about Zindi points here.

Competition closes on 16 February 2025.

Final submissions must be received by 11:59 PM GMT.

We reserve the right to update the contest timeline if necessary.

How to enroll in your first Zindi competition

How to create a team on Zindi

How to update your profile on Zindi

How to use Colab on Zindi

How to mount a drive on Colab

• Languages and tools: You may only use open-source languages and tools in building models for this challenge.
• Who can compete: Open to all
• Submission Limits: 10 submissions per day, 300 submissions overall.
• Team size: Max team size of 4
• Public-Private Split: Zindi maintains a public leaderboard and a private leaderboard for each challenge. The public leaderboard includes approximately 30% of the test dataset. The private leaderboard will be revealed at the close of the challenge and contains the remaining 70% of the test set.
• Data Sharing: CC-BY SA 4.0 license
• Platform abuse: Multiple accounts, or sharing of code and information across accounts not in teams, or any other forms of platform abuse are not allowed, and will lead to disqualification.
• Code Review: Top 10 on the private leaderboard will receive an email requesting their code at the close of the challenge. You will have 48 hours to submit your code.

ENTRY INTO THIS CHALLENGE CONSTITUTES YOUR ACCEPTANCE OF THESE OFFICIAL CHALLENGE RULES.

Full Challenge Rules

This challenge is open to all.

Teams and collaboration

You may participate in challenges as an individual or in a team of up to four people. When creating a team, the team must have a total submission count less than or equal to the maximum allowable submissions as of the formation date. A team will be allowed the maximum number of submissions for the challenge, minus the total number of submissions among team members at team formation. Prizes are transferred only to the individual players or to the team leader.

Multiple accounts per user are not permitted, and neither is collaboration or membership across multiple teams. Individuals and their submissions originating from multiple accounts will be immediately disqualified from the platform.

Code must not be shared privately outside of a team. Any code that is shared, must be made available to all challenge participants through the platform. (i.e. on the discussion boards).

The Zindi data scientist who sets up a team is the default Team Leader but they can transfer leadership to another data scientist on the team. The Team Leader can invite other data scientists to their team. Invited data scientists can accept or reject invitations. Until a second data scientist accepts an invitation to join a team, the data scientist who initiated a team remains an individual on the leaderboard. No additional members may be added to teams within the final 5 days of the challenge or last hour of a hackathon.

The team leader can initiate a merge with another team. Only the team leader of the second team can accept the invite. The default team leader is the leader from the team who initiated the invite. Teams can only merge if the total number of members is less than or equal to the maximum team size of the challenge.

A team can be disbanded if it has not yet made a submission. Once a submission is made individual members cannot leave the team.

All members in the team receive points associated with their ranking in the challenge and there is no split or division of the points between team members.

Datasets and packages

The solution must use publicly-available, open-source packages only.

You may use only the datasets provided for this challenge. Automated machine learning tools such as automl are not permitted.

You may use pretrained models as long as they are openly available to everyone.

You are allowed to access, use and share challenge data for any commercial,. non-commercial, research or education purposes, under a CC-BY SA 4.0 license.

You must notify Zindi immediately upon learning of any unauthorised transmission of or unauthorised access to the challenge data, and work with Zindi to rectify any unauthorised transmission or access.

Your solution must not infringe the rights of any third party and you must be legally entitled to assign ownership of all rights of copyright in and to the winning solution code to Zindi.

Submissions and winning

You may make a maximum of 10 submissions per day.

You may make a maximum of 200 submissions for this challenge.

Before the end of the challenge you need to choose 2 submissions to be judged on for the private leaderboard. If you do not make a selection your 2 best public leaderboard submissions will be used to score on the private leaderboard.

During the challenge, your best public score will be displayed regardless of the submissions you have selected. When the challenge closes your best private score out of the 2 selected submissions will be displayed.

Zindi maintains a public leaderboard and a private leaderboard for each challenge. The public leaderboard includes approximately 30% of the test dataset. While the challenge is open, the public leaderboard will rank the submitted solutions by the accuracy score they achieve. Upon close of the challenge, the private leaderboard, which covers the other 70% of the test dataset, will be made public and will constitute the final ranking for the challenge.

Note that to count, your submission must first pass processing. If your submission fails during the processing step, it will not be counted and not receive a score; nor will it count against your daily submission limit. If you encounter problems with your submission file, your best course of action is to ask for advice on the Competition’s discussion forum.

If resource restrictions are indicated on the challenge page you must adhere to them.

If you are in the top 10 at the time the leaderboard closes, we will email you to request your code. On receipt of email, you will have 48 hours to respond and submit your code following the Reproducibility of submitted code guidelines detailed below. Failure to respond will result in disqualification.

If your solution places 1st, 2nd, or 3rd on the final leaderboard, you will be required to submit your winning solution code to us for verification, and you thereby agree to assign all worldwide rights of copyright in and to such winning solution to Zindi.

If two solutions earn identical scores on the leaderboard, the tiebreaker will be the date and time in which the submission was made (the earlier solution will win).

The winners will be paid via bank transfer, PayPal if payment is less than or equivalent to $100, or other international money transfer platform. International transfer fees will be deducted from the total prize amount, unless the prize money is under $500, in which case the international transfer fees will be covered by Zindi. In all cases, the winners are responsible for any other fees applied by their own bank or other institution for receiving the prize money. All taxes imposed on prizes are the sole responsibility of the winners. The top winners or team leaders will be required to present Zindi with proof of identification, proof of residence and a letter from your bank confirming your banking details. Winners will be paid in USD or the currency of the challenge. If your account cannot receive US Dollars or the currency of the challenge then your bank will need to provide proof of this and Zindi will try to accommodate this.

Please note that due to the ongoing Russia-Ukraine conflict, we are not currently able to make prize payments to winners located in Russia. We apologise for any inconvenience that may cause, and will handle any issues that arise on a case-by-case basis.

Payment will be made after code review and sealing the leaderboard.

You acknowledge and agree that Zindi may, without any obligation to do so, remove or disqualify an individual, team, or account if Zindi believes that such individual, team, or account is in violation of these rules. Entry into this challenge constitutes your acceptance of these official challenge rules.

Zindi is committed to providing solutions of value to our clients and partners. To this end, we reserve the right to disqualify your submission on the grounds of usability or value. This includes but is not limited to the use of data leaks or any other practices that we deem to compromise the inherent value of your solution.

Zindi also reserves the right to disqualify you and/or your submissions from any challenge if we believe that you violated the rules or violated the spirit of the challenge or the platform in any other way. The disqualifications are irrespective of your position on the leaderboard and completely at the discretion of Zindi.

Please refer to the FAQs and Terms of Use for additional rules that may apply to this challenge. We reserve the right to update these rules at any time.

Reproducibility of submitted code

• If your submitted code does not reproduce your score on the leaderboard, we reserve the right to adjust your rank to the score generated by the code you submitted.
• If your code does not run you will be dropped from the top 10. Please make sure your code runs before submitting your solution.
• Always set the seed. Rerunning your model should always place you at the same position on the leaderboard. When running your solution, if randomness shifts you down the leaderboard we reserve the right to adjust your rank to the closest score that your submission reproduces.
• Custom packages in your submission notebook will not be accepted.
• You may only use tools available to everyone i.e. no paid services or free trials that require a credit card.

Documentation

A README markdown file is required

It should cover:

• How to set up folders and where each file is saved
• Order in which to run code
• Explanations of features used
• Environment for the code to be run (conda environment.yml file or an environment.txt file)
• Hardware needed (e.g. Google Colab or the specifications of your local machine)
• Expected run time for each notebook. This will be useful to the review team for time and resource allocation.

Your code needs to run properly, code reviewers do not have time to debug code. If code does not run easily you will be bumped down the leaderboard.

Consequences of breaking any rules of the challenge or submission guidelines:

• First offence: No prizes for 6 months and 2000 points will be removed from your profile (probation period). If you are caught cheating, all individuals involved in cheating will be disqualified from the challenge(s) you were caught in and you will be disqualified from winning any challenges for the next six months and 2000 points will be removed from your profile. If you have less than 2000 points to your profile your points will be set to 0.
• Second offence: Banned from the platform. If you are caught for a second time your Zindi account will be disabled and you will be disqualified from winning any challenges or Zindi points using any other account.
• Teams with individuals who are caught cheating will not be eligible to win prizes or points in the challenge in which the cheating occurred, regardless of the individuals’ knowledge of or participation in the offence.
• Teams with individuals who have previously committed an offence will not be eligible for any prizes for any challenges during the 6-month probation period.

Monitoring of submissions

• We will review the top 10 solutions of every challenge when the challenge ends.
• We reserve the right to request code from any user at any time during a challenge. You will have 24 hours to submit your code following the rules for code review (see above). Zindi reserves the right not to explain our reasons for requesting code. If you do not submit your code within 24 hours you will be disqualified from winning any challenges or Zindi points for the next six months. If you fall under suspicion again and your code is requested and you fail to submit your code within 24 hours, your Zindi account will be disabled and you will be disqualified from winning any challenges or Zindi points with any other account.