equilibrated dry beach widths compared to sand the same size as (or larger than) native sand. Evaluating material fit requires a sand survey that usually includes geophysical profiles and surface and core samples. Some beaches were nourished using a finer sand than the original. Thermoluminescence monitoring reveals that storms can erode such beaches far more quickly. This was observed at a Waikiki nourishment project in Hawaii. Profile nourishment Beach Profile Nourishment describes programs that nourish the full beach profile. In this instance, "profile" means the slope of the uneroded beach from above the water out to sea. The Gold Coast profile nourishment program placed 75% of its total sand volume below low water level. Some coastal authorities overnourish the below water beach (aka "nearshore nourishment") so that over time the natural beach increases in size. These approaches do not permanently protect beaches eroded by human activity, which requires that activity to be mitigated. Project impact measurements Nourishment projects usually involve physical, environmental and economic objectives. Typical physical measures include dry beach width/height, post-storm sand volume, post-storm damage avoidance assessments and aqueous sand volume. Environmental measures include marine life distribution, habitat and population counts. Economic impacts include recreation, tourism, flood and "disaster" prevention. Many nourishment projects are advocated via economic impact studies that rely on additional tourist expenditure. This approach is however unsatisfactory. First, nothing proves that these expenditures are incremental (they could shift expenditures from other nearby areas). Second, economic impact does not account for costs and benefits for all economic agents, as cost benefit analysis does. Techniques for incorporating nourishment projects into flood insurance costs and disaster assistance remain controversial. The performance of a beach nourishment project is most predictable for a long, straight shoreline without the complications of inlets or engineered structures. In addition, predictability is better for overall performance, e.g., average shoreline change, rather than shoreline change at a specific location. Nourishment can affect eligibility in the U.S. National Flood Insurance Program and federal disaster assistance. Nourishment may have the unintended consequence of promoting coastal development, which increases risk of other coastal hazards. Other shoreline protection approaches Nourishment is not the only technique used to address eroding beaches. Others can be used singly or in combination with nourishment, driven by economic, environmental and political considerations. Human activities such as dam construction can interfere with natural sediment flows (thereby reducing riverine sediment sources.) Construction of littoral barriers such