Between government bodies , charities of every size, and contributions from concerned individuals, a massive Hurricane Harvey relief effort has taken shape in the US. But these well-intentioned bids to ship goods to Texas are perpetuating a common myth of post-disaster charitable giving.

As a researcher with the Harvard Humanitarian Initiative, acentre at Harvard University dedicated to analysing and improving the way professionals and communities respond to emergencies, I’ve seen the evidence on dozens of disasters, from Hurricane Sandy to the Indian Ocean tsunami in 2004. It all points to a clear conclusion: in-kind donations of items such as food, clothing, toiletries and nappies are often the last thing that is needed in these areas.

Delivering things that people need on the ground simply doesn’t help disaster-struck communities as much as giving them – and relief organisations – money to buy what they need.

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What’s wrong with in-kind donations?

At best, in-kind donations augment official efforts and provide the locals with some additional comfort, especially when those donations come from nearby. When various levels of government failed to meet the needs of Hurricane Katrina victims, for example, community, faith-based and private sector organisations stepped in to fill many of the gaps.

But truckloads of donations can actually interfere with official relief efforts. While ostensibly free, donated goods actually raise the cost of the response: from collecting, sorting, packaging and shipping bulky items across long distances, to the reception, sorting, warehousing and distribution upon their arrival.

All of this in areas where the transportation infrastructure, such as airports, roads and bridges, are likely to be, if not damaged or incapacitated by the initial disaster, already clogged by first responders and their equipment. It also diverts personnel, trucks and storage facilities from actual relief efforts.

Dumping grounds

At worst, disaster zones become dumping grounds for inappropriate goods that delay appropriate relief efforts and harm local economies.

After the 2004 tsunami, shipping containers full of items such as used high-heeled shoes, ski gear and expired medicine poured into the affected countries. After the 2010 earthquake in Haiti, many untrained and uninvited American volunteers bringing unnecessary goods ended up needing assistance themselves.

One study led by José Holguín-Veras, an expert on humanitarian logistics, found that 50% to 70% of the goods that arrive during emergencies such as the 2011 tornado in the US and the earthquake in Japan, should never have been sent and interfere with recovery efforts. In these cases, excessive donations of clothing and blankets tied up relief personnel. The situation was similar after Hurricane Katrina.

Relief workers consider these well-meaning but inconvenient donations a “second-tier disaster” due to the disruption they cause.

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What else can you do?

Instead of shipping your hand-me-downs, donate money to trusted and established organisations with extensive experience and local ties to the effected areas.

Give to groups that make it clear where the money will go. Choose relief efforts that will procure supplies near the disaster area, which will help the local economy recover. Many humanitarian aid organisations themselves have increasingly adopted cash-based approaches in recent years, although money remains a small share of overall humanitarian aid worldwide.

The effectiveness of such programmes vary, but emerging evidence suggests that disbursing cash is often the best way to help people in disaster zones get the food and shelter they need. What’s more, the World Food Program and the UN High Commissioner for Refugees say that people affected by disasters tend to prefer cash over in-kind aid due to the dignity, control and flexibility it gives them.

Of course, there are always exceptions. If you live in or near an affected area, it is helpful to consider donate specific requested items to local food banks, shelters and other community organisations. Just make sure that the items won’t perish by the time they can be distributed. Donations might include nappies, cleaning and building supplies and new bedding.

Charity is a virtue and the urge to help when a disaster hits is admirable. Yet this impulse should be channeled to do the greatest good. Let the professionals procure the goods and services they need, in response to the people on the ground.

Most importantly, don’t stop giving after the disaster stops making headlines. A full recovery will take time and require support long after the emergency responders and camera crews have moved on.

This article was originally published on The Conversation, part of the Guardian Comment Network.

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