Few events provided such a stark illustration of Honolulu's desperate lack of affordable housing as the partial collapse of the makeshift multi-family dwelling in Kalihi this week.

The Gulick Avenue address was home to some 50 people living in a cobbled-together, illegal structure on the property. They were paying up to $750 each month; some reported that it was preferable to living in their car or any other alternative they could find.

It was the cause of dozens of complaints, mainly about the structural violations but also from sanitation concerns.

A series of violations over the past five years led to notices; some problems were corrected, but ultimately the illegal structure was built and drew down daily fines dating to October 2005. The persistence of the structure stands as testimony to the legal complexities involved in correcting substandard housing and resolving safety concerns.

For the state's part, health officials fielded calls over the course of more than two years from neighbors reporting odor, garbage and rodents on the property; some alleged finding fecal matter on the ground and a makeshift toilet.

Shutting down this operation proved difficult; state health inspectors went out on three occasions, accompanied once by a city plumbing inspector, but found the violations corrected upon their arrival. Warnings were sent about the rodent problem.

The bulk of the complaints concerned the unpermitted structure itself, a jumble of steel poles, tarps and plywood platforms. This week the city Department of Planning and Permitting (DPP) blocked off entry to the property, posting a notice of building violations. It also is exploring foreclosure for failure to pay $53,000 in fines.

Elected officials and city and state agencies need to find ways to bring these problems to a close more efficiently.

But beyond the health and safety concerns, the fact that dozens of people were willing to live in substandard conditions speaks volumes about the "hidden homeless" in Hawai'i, particularly on O'ahu. The problem is far worse than most people imagine. According to the state's Hawai'i Housing Policy Study, the number of "hidden homeless" — people from multiple households living in single-family units — hovers around the 100,000. Even more are a paycheck away from being on the streets.

In a faltering economy the pressure to find affordable rentals will worsen, and this crisis demands prompt attention from city and state leaders.