Chennai floods and India rains
People travel on a boat as they move to safer places through a flooded road in ChennaiReuters

The south Indian state of Tamil Nadu has been declared a "disaster zone" as heavy flooding has killed at least 290 people. The Indian army has been deployed to rescue thousands of people who are stranded after the region received the heaviest rainfall in a century.

While rainfall has ceased for the moment, thousands still remain trapped or displaced due to the heavy flooding. Over the last few days social media users have rallied together to send their prayers for the victims, with many also using social media to coordinate aid relief efforts. The hashtag #ChennaiRainsHelp has been widely circulated and used to organise a number of different donation drives and other ways to help those who have been affected by the floods.

A number of organisations and NGOs have also begun conducting relief work on the ground and are accepting donations, however, it is understandable that many might not be in a position to donate money to the cause. Therefore, IBTimes UK has rounded up ten ways that you can help the victims – without having to spend a rupee.

1. Donate a room

One of the most serious problems at the moment appears to be with those who have been forced out of their homes. Videos have circulated the Internet over the last few days showing homes completely flooded – with water reaching the second floor in many instances. Therefore, dozens of people across the city have begun opening their doors to those in need. If you live in the region and have some spare room in your house, you can sign up to the room sharing database here.

2. Volunteer your time

Many groups have begun collecting a number of supplies such as food, water and medical equipment. However, a lot of them are now struggling to deliver these supplies in a timely manner to those who need it. If you're in the area, you can donate your time and help with the distributions.

It can be difficult to estimate when and where volunteers will be required with distributions as the need for this comes and goes as required. However, the best places to look for opportunities to volunteer your time are on ChennaiRains.org and on this Twitter thread. For those looking to volunteer their time in other ways, you can sign up through this form to offer your skills in any area.

Furthermore, follow the Chennai Rain Relief team on Facebook to keep up-to-date with donation and volunteer requests from the ground.

3. Donate food and medical supplies (and other items)

While you might not be able to donate cash, there is always a need for food, water and medical supplies. Many people have posted on ChennaiRains.org to request these items and you can filter your search by typing in "food" or "medical supplies" in the search bar and then getting in touch with the relevant people directly.

For those who are outside the region, charity organisation Goonj is collecting a number of other necessary supplies as well, including blankets, bed sheets, utensils, raincoats, slippers, clothing, toiletries and other items. Donations can be dropped off at one of their offices across the country (Delhi, Mumbai, Bangalore, Hyderabad, Kolkata and Rishikesh). Visit their website for more information.

Some organisations in the region are also offering services to pick up donated items directly from your doorstep. Ola Cabs and Uber are among these organisations.

4. Conduct safety checks

Available on a rolling basis, a number of people are searching for their friends and family who they haven't heard from and are unable to reach. Many people posting on here are based outside India and are unable to check on their loved ones themselves. If you're in the region and are willing to conduct a safety check for someone, ChennaiRains.org offers a full list of those who are looking for their family/friends, as well as the details about where their loved one is located in Chennai. Simply type "safety check" into the search bar to filter the options and find out who you can conduct a safety check for. The hashtag #ChennaiVolutneer also has many messages from people asking for someone to check on people they know.

5. Verify and update aid messages on Twitter

This one is for those who want to help no matter where in the world they are. With an increasing number of aid messages being sent out on Twitter, it becomes difficult for people to know which ones are the most recent and which ones are now out of date. A call has been put out for volunteers to scan through the messages on #ChennaiRainsHelp and if you come across any tweets that are more than two hours old, you are advised to call the number and verify the situation. You are then asked to retweet the tweet with the words "verified".

The call also requests volunteers to help clean up the hashtag by checking the timelines of those who are offering help and if there has been an update to a specific aid message, you are requested to approach the Twitter user and ask them to delete their out-of-date message to avoid any confusion.

6. Report flooded streets

A crowdfunding initiative has been launched to report any flooded streets in Chennai so that rescue teams can effectively deal with the situation. If you're in the region and are able to accurately report streets that have been affected by the flooding, visit the flooded streets website and update the map.

7. Know your Twitter hashtags

While many will be quick to take to social media to post messages of solidarity, it's important to ensure that your messages – and others' messages – aren't interrupting useful aid relief work. Those working in the region have issued a number of notices alerting people to use the relevant hashtags for their tweets, depending on what their message is about. Here are some of the most popular hashtags associated with the floods and how best to use them:

#ChennaiFloods: A general hashtag for everything related to the disaster, including messages of solidarity and updates on the situation.

#ChennaiRainsHelp: Firm requests for this hashtag not to be used unless you are offering aid in some way or are seeking aid.

#ChennaiVolunteer: Must only be used if you are offering your volunteering services or advertising for volunteers to help with the disaster in some way.

8. Top up a phone for free

Many on social media are offering to top up the phones of those who have run out of credit. Airtel, Vodafone and Paytm are among those networks that are offering free talk time for those affected by the Chennai floods. Search the #ChennaiRainsHelp hashtag for those who are in need of a top up, get their number from them, and offer to top up their phone for them so that they can contact their loved ones. Airtel is offering 10 minutes of free talk time with 50MB of mobile data, while Paytm is offering 30 minutes of free talk time.

9. Give a meal

Wherever you are in India, you can order a meal for a flood victim through Zomato. Not only that, but Zomato will also match your donation by providing an extra meal for someone affected by the disaster. The service has already had up to 55,000 orders and have delivered 110,000 meals.

10. Share Google's Crisis Response tool

Finally, Google has launched a Crisis Response tool that rounds up everything people need to know about the disaster region, including useful emergency numbers. No matter where in the world you are, sharing this page is going to undoubtedly help many get access to all the information they need through one webpage. It also rounds up useful messages on Twitter and weather updates for the region.