Honolulu has hovered like a mother hen over Waikiki for more than a century, starting with plans for draining its wetlands for the good of public health.

That concern intensified with its development as a resort, and the city responded by designating the area in 1976 as a special design district.

There is good reason to hover: The urban resort is a primary economic engine for the state, and extra steps should be taken to keep tabs on its growth.

This was the reason behind multiple plans prepared over the years, including the 1996 Planning Department Report that assessed infrastructure, asserting that "improvements can and should be made on a continuing basis."

In 2006 the City Council adopted a resolution asking the Department of Planning and Permitting to study the carrying capacity of existing infrastructure in Waikiki or at least to update the 1996 report.

The department has acknowledged that this update hasn't been done, owing to demands on staffing and other priorities. Its director, Henry Eng, has affirmed, however, that permit applications for development aren't approved unless the capacity of streets, sewers, water and power can support projects.

But the fact remains that a broad survey of utilities and other needs would be a critical tool for policymakers who want to keep the district healthy and thriving for years.

City planners may be able to assess the needs of specific projects, but there may be zones within Waikiki that are nearing limits. The correct response may be to make changes or add restrictions, but elected leaders need to be armed with enough information to guide these decisions.

The council should underscore its simple request for an updated study by allotting the money to hire a consultant and setting a deadline.

Some residents have expressed a perception that growth is not under control. What's needed is an expert who can pull together the data for a comprehensive view, so leaders can decide how to shape Waikiki's future.