Any number of different project factors can wipe out the search presence of a Web site that is performing well. A few of the more commonly known natural born search killers include Flash, hidden content and non-search-friendly content management systems. Much has been written on each of these topics, so I want to take this time to shed some light on a lesser-known element that has just as much potential to make or break natural search presence: changing a URL structure.

The hidden search killer

One element of redesign that has a major impact on search investments is the treatment of URL equity, which is the sum of several important values tied into URL structure. Changing domains or renaming existing deep URL structures without a solid strategy can wipe out years of gains in links, traffic, sales and conversions, and prior natural search investments.

Over the last few years I have observed that client indifference to URL strategy has consistently been a major threat to a search presence. Being indifferent about URLs means that a single variable implemented in the development or planning process has the potential to erase years of positive gains. Rather than taking recommended preventive and transitional measures, most clients go into reactive mode and attempt to patch up issues than cannot be fully repaired. The impact is felt in years of lost links, lost search engine traffic, dramatic loss of indexed pages, lost sales and conversions, and lost search investments.

I am not suggesting that sites should never be redesigned, or that URLs should not be renamed. There are many legitimate reasons to alter URLs, including revamping of the user path and experience, changing technical platforms, or removing content. A redesign should be treated as an opportunity to bridge current equity and to maintain a sustainable URL structure that will position a site for a long-term positive natural search presence. Understanding the inherent value of URLs will not only help bridge accrued natural search gains, but also bridge a site's search engine reputation for years to come.

The elements of URL equity

Uniform Resource Locators (also known as Uniform Resource Identifiers or URIs) are the axis point for all traffic that runs throughout a site. A site's URL equity is composed of the following elements:

Link equity: This is the positive buildup of links over time, both to the home page and the internal URL structure of a site. Links may come from many places such as blogs, newspaper sites, authority sites, directories or internal site pages. It is not uncommon for many major brands to have hundreds of thousands, or even millions of quality links pointing to a domain and deep internal site structures. Links and other "off-the-page" factors are now the most crucial element in how search engines retrieve their results. Preservation of existing links alone is a strong enough reason to maintain URL equity and natural search engine presence.

Where there is link equity, there can also be link liability. If a domain or URL has been banned in an engine due to bad linking practices, then another URL name may be considered.

Positive search engine equity: Positive search engine equity is gained from the history of search engine crawling, indexing and retrieving over time. URLs are like a serial number for a document, and search engines use domains and internal URLs as the reference point for these processes. For sites that do not spam and have a positive history with the search engines, URLs become more trusted over time.

Using new URLs or domains in a redesign means that engines must start the crawling, indexing, and retrieval processes over again. Search optimizers share the common knowledge that legacy domains and trusted URLs are like gold; if a domain or trusted URL structure is several years old or older, there is a distinct advantage over sites built on newer domains and structures. As I mentioned above, a current or previous ban in the engines indicates a liability. In that case, renaming may still be a positive step for a redesign.

Bookmark equity: One additional (and often overlooked) factor in assessing URL equity is bookmark traffic. A bookmark represents a site conversion for visitors who have found useful content and will return later. Failure to bridge the gap for converted visitors is a poor usability experience, because these visitors are left hanging with their intentions unfulfilled.

Search investment: Costs are incurred whether natural search is performed in-house, by an agency or by a consultant. When URLs change without a plan, there is a risk of completely wiping out search investments. This could include previous link development campaigns, general site promotion designed to drive traffic to deep site URLs, or implementation of general search engine-based Web design practices.

In the next installment of this column, I will discuss the deeper impact of changing URLs in a site redesign, bridging URL structures and placing value on site URLs.

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