In determining the effectiveness of an Urban Growth Boundary, which indicator best measures its impact on housing affordability?

• A. Changes in housing supply and affordability metrics inside vs outside the boundary over time.
• B. Population growth near the boundary.
• C. Number of new business licenses issued.
• D. Traffic volumes on major corridors.

Answer: (D)

The question focuses on how to judge whether an Urban Growth Boundary actually affects housing affordability. The most direct and informative indicator is tracking changes in housing supply and affordability metrics inside the boundary versus outside the boundary over time. This comparison shows whether restricting or guiding growth within the boundary leads to shifts in how much housing is built, at what price or rent, and how those costs relate to incomes. It captures the policy’s intended effect on supply and cost, rather than secondary signals.

Population growth near the boundary can signal demand but doesn’t directly measure affordability outcomes. The number of new business licenses reflects economic activity, not housing conditions. Traffic volumes on major corridors reflect transportation demand and congestion, not housing costs or supply. So, for assessing affordability impacts, focus on housing supply and affordability metrics inside versus outside the boundary over time.