This METRO code requires cities and counties to consider Financial incentives if development is not dense enough

3.07.140 Requirements to Increase Capacity If Recent Development At Low Density

A. All cities and counties shall determine whether actual built densities for housing during 1990-1995 were less than 80 percent of maximum zoned densities. The 1990-1995 actual built densities within cities and counties inside the urban growth boundary shall be compared with zoned densities for housing units during that period. Residential developments to be analyzed shall be those which were permitted by a land use action and constructed during the period from 1990 to 1995, and residential density shall be measured in households per net developed acre.3

B. If the comparison of actual built densities to maximum zoned densities for the period 1990-1995 indicates that actual built densities were less than 80 percent of maximum zoned densities, the city or county shall also demonstrate that it has considered and adopted at least two of the following methods to increase capacity:

1. Financial incentives for higher density housing;
2. Provisions permitting additional density beyond that generally allowed in the zoning district in exchange for amenities and features provided by the developer;
3. Removal or easing of approval standards or procedures;
4. Redevelopment and infill strategies; and
5. Authorization of housing types not previously allowed by the plan or regulations.

(Ordinance No. 97-715B, Sec. 1.)

The above is on page 3.07 - 9 of METRO's code. See: