Singapore experiences an average of 167 rain days in a year, including 31 to 73 days classified as heavy rain days (based on 10 years of data).
Today, PUB is relying on 81 units of rain gauges across 710 km2 of land area to monitor rainfall across the entire island. Due to World Meteorological Organization’s requirements as well as limited suitable sites for installing rain gauges, there will be locations where rain gauges are sited as far as 3-5km away from each other. This results in the problem whereby the nearest rain gauges are too far to give representative readings of the rain intensity in certain areas.
Due to the convective nature of Singapore’s weather system, the rainfall in Singapore can vary significantly spatially and temporally. It is important that PUB obtains adequate rainfall data to support decisions to deploy flood management resources. The existing density of the rain gauge network does not provide enough resolution of the rainfall distribution and therefore, there have been instances in which the nearest rain gauge does not capture the actual rainfall at a location at a particular moment because it is sited outside the localised heavy rain area.
- The sensors must be appropriately sized (in terms of dimensions and weight) to be retrofitted to the top of public infrastructure such as lamp posts, bus stops, moving buses or HDB flats. Their weight shall not exceed the allowable designed loading on top of the infrastructure and in accordance with LTA or other relevant government requirements.
- Each installation shall be approved by a professional engineer (Civil) with endorsed structural calculations as well as relevant government agencies.
- The sensors must be self-powered and can be recharged using solar or renewable sources.
- The sensor should ideally require minimal maintenance. The accuracy or functionality of the sensor must be minimally impacted when subjected to outdoor conditions, for example, falling leaves, bird droppings, extreme heat due to the sun, lightning.
- The transmission of rainfall data must be done in real-time at 5-minute intervals from the onset of rain.
- When drift in data accuracy is observed, rectification works should be carried out within 6 hours.
- The sensors need to measure precipitation (mm) and transmit the data wirelessly in real time.
- Proposed method statements for the calibration and preventive/corrective maintenance to ensure continuous operation of the sensors and the accuracy of the sensors, shall be provided. The method statements shall take into account safety considerations to access the sensors and to carry out the work.
- The rainfall measurements provided by the sensor or proposed technology should be bench-marked with rain gauges for accuracy. This should be tested and verified according to a sound scientific methodology or certified by relevant Qualified Person.
- The rainfall measurements provided by the sensor or proposed technology shall minimally achieve within +/- 15% of rainfall measurements provided by rain gauges
Current Technology Status
Existing Rain Gauge
- Have stringent installation requirements which limits the number of suitable sites.
Use of AI/machine learning to estimate rainfall intensity from CCTV images
- Already being explored by PUB to provide rainfall intensity estimation.
- The number of CCTVs is limited, and it is not cost effective to install new CCTVs solely for the purpose of estimating rainfall intensity
- Technology has limited applications in the evening/at night due to poor lighting conditions of the CCTV images
In order to support companies with innovative solutions to collaborate with PUB, we have lined up pilot funding, mentors, data, test sites, and other resources to support pilot projects.
PUB is committed to providing funding support to help cover the costs of development and test-bedding. This includes manpower, equipment and material costs. Shortlisted companies will receive initial funding of up to SG$250,000 for each pilot project.
Where the company already has basic technological components of the prototype or even a ready solution, the funding can be used to refine the solution based on the site requirements. The solution shall be developed to have systems and processes in place to support actual operations. By the end of the project, a system or process demonstration is carried out in an operational environment.
Where the company needs to perform activities involving design, development and controlled testing of technological components, the funding can be used for hardware and other development and testing. By the end of the prototyping phase, basic technological components shall be integrated to establish that they will work together. The resulting prototype is expected to have relatively “low fidelity” in comparison with the eventual system.
More information on the pilot requirements for each challenge is provided under Challenges.
Upon being selected for funding through the PUB Global Innovation Challenge, companies can submit their funding request along with a detailed pilot proposal. The proposal and funding request will then be reviewed by PUB’s Project Evaluation Panel. More than one company per challenge could eventually receive the funding.
The awardees will be required to propose a payment schedule based on significant milestones, so that payment can be made progressively throughout the pilot project upon attainment of each milestone.
If the pilot project proves to be successful, the awardee will have access to additional funding for further development and testing, or contracts for deployment of the solution.
Mentorship by PUB Experts
If selected for the Pilot Phase, companies will be matched to relevant department(s) and receive mentorship from PUB’s experts. The companies will be able to leverage on their insights and past learnings to accelerate the development of their solution(s) for the water industry.
For each of the challenges, PUB has prepared test sites, data and other internal resources so that solutions can be tested under real conditions and demonstrate valid results.
Commercialisation of Opportunities
If the pilot proves successful, PUB is best positioned to help commercialise and scale the product. The Singapore Water Exchange, which is run by PUB, houses entrepreneurs, startups, investors, accelerators, incubators, market advisors, technology providers, equipment suppliers, research institutes, system integrators and associations to support R&D and help companies build capabilities.