Zoning in Juneau, Alaska: The Landslide and Avalanche Hazard Map Fight

Why Juneau remapped: modern modeling replacing 1970s/1980s-era hazard maps

Juneau's steep, glacier-carved terrain has made landslide and avalanche hazard a real land-use factor for decades, and the city's original hazard maps -- dating to the 1970s and refined through the 1980s -- were the basis for development restrictions that have shaped downtown building for more than 40 years. Those older maps combined landslide and avalanche risk into a single hazard category and relied on modeling techniques that have since been substantially superseded. In 2018, the City and Borough of Juneau secured a FEMA grant specifically to redo the mapping with current scientific analysis, contracting engineering firm Tetra Tech Inc. to run the project.

The resulting maps, completed in 2021, are a genuinely more detailed product: rather than one combined hazard designation, they present separate landslide and avalanche layers, each broken into four categories -- low, moderate, high, and severe. That granularity is valuable for understanding risk precisely, but it also produced a materially larger hazard footprint than the older combined maps had shown: roughly 550 structures across the city, about half of all buildings and homes in the downtown area specifically, now fall into the moderate-to-severe range. One of the clearest documented risk corridors sits below the Behrends avalanche path, visible as a treeless swath on the flank of Mt. Juneau overlooking the downtown core.

The unresolved fight: repeal the old restrictions, or adopt the new map's findings?

Completing a more accurate hazard map turned out to be only half the story. The 1980s-era development restrictions tied to the original combined maps -- limits on new construction, and in some cases requirements for engineering mitigation, within identified hazard boundaries -- have remained in place for decades and directly govern what an owner can build on an affected downtown parcel. Rather than simply substituting the new 2021 map's more detailed (and in many cases more expansive) hazard zones into that same restriction framework, Juneau's Assembly opened a genuine policy debate: as of September 2023, members were actively considering whether to repeal or significantly revise those restrictions rather than tighten them to match the new data.

That's a real, live tension for anyone evaluating downtown-adjacent Juneau land: the new maps identify more at-risk structures and lots than the old ones did, but the actual legal restriction that applies to a specific parcel depends on how the Assembly's debate is ultimately resolved -- repeal, revision, or adoption of the 2021 findings as-is. This page cannot tell you which outcome has prevailed since September 2023; what it can tell you is that this is not settled, decades-old policy sitting quietly on the books, but an active question the city was reconsidering as of the most recent confirmed reporting.

What this means for evaluating a Juneau parcel

1. Get the specific parcel checked against the 2021 hazard maps directly with CBJ Community Development -- don't rely on a general sense of whether 'downtown Juneau' or a particular street is risky, since the maps assign hazard category at a granular, near-parcel level.
2. Ask directly whether the Assembly's 2023 debate over repealing or revising the 1980s-era development restrictions has since concluded, and if so, which restriction regime (the original 1980s rule, a revised version, or none at all) currently governs a hazard-zone parcel.
3. If a specific structure or building site falls in a moderate-to-severe zone under either the old or new maps, ask what engineering mitigation options (if any) the borough currently allows as a path to building there, rather than assuming the zone is an automatic bar.
4. This episode is also a useful general signal for buyers with no specific downtown interest: it shows Juneau's land-use rules in hazard-prone areas are actively being reconsidered in the 2020s, not frozen in the 1980s -- confirm current code text rather than relying on an older summary of the rule.