The lack and loss of affordable housing is more and more being seen as a crisis that is affecting the short- and long-term prosperity, amenity and even viability of the city of Portland.

Real estate developers are using this growing concern to seek relaxation in zoning restrictions to permit increased density in the most desirable residential quarters of the city.

The result of these efforts, paradoxically, is a decrease in currently available affordable housing with nothing affordable to replace it. Any strategy to stem and reverse the ongoing loss of affordable living units in Portland must be designed to retain and protect existing resources as well as focus future development on affordable rental units rather than high-end leisure condominiums.

For some time now, the spiraling costs of building materials and labor have made the construction of new affordable dwelling units in Portland economically impossible without significant public subsidy. Unless we are prepared to come up with massive subsidies for new construction, this means that virtually all potential affordable dwelling units in Portland have already been built. Conserving those units and supporting their ongoing rental at affordable rates has to be the first priority.

Munjoy Hill, densely packed with one- to three-family wood-frame houses plus two large subsidized housing developments, has traditionally provided a great deal of affordable housing within the city. In recent years, however, developers have torn down more than 40 affordable units there and replaced them with high-end condominium blocks that in no way qualify as affordable. Airbnb conversions have taken another 140 affordable dwelling units out of circulation on the Hill alone and nearly 1,000 out of the city of Portland.

The first step in addressing our affordable-housing crisis must be to stem the losses of our existing affordable units. This can be addressed by:

• Restraining demolition of any affordable dwelling unit (regardless of condition) unless the developer can provide an additional dwelling unit that can be rented at the same rent – no “buyouts.”

• Regulating the conversion of affordable dwelling units into Airbnb by limiting owner-occupied Airbnb units to one per owner and prohibiting Airbnb in buildings not occupied by the owner.

• Supporting the stability and maintenance of affordable neighborhoods with protective zoning and historic district designations where justified.

• Extending federal historic district tax credit eligibility in qualifying affordable neighborhoods.

• Promoting legislation for “current-use-based” real estate taxation for dwellings rented at affordable rents – similar to farmland, waterfront and tree-growth taxation.

Some combination of these measures might have a chance of slowing the loss of existing affordable-housing units in Portland. Now what can be done about adding more?

Here are some proposals:

• Prioritize and support traditional programs of subsidized affordable housing by the Portland Housing Authority and qualified developers building under federally subsidized programs.

• Make city-owned land available for development as affordable housing on long-term leases with suitable restrictions – e.g., the site of the former proposed midtown development in Bayside could be developed for affordable housing in a public-private partnership.

• Qualify historically significant areas of the city for federal historic tax credits that could help with the rehabilitation and construction of appropriate infill affordable housing.

• Consider the use of real estate tax breaks for developers of affordable housing.

• Allow compatible two-family and three-family houses (but not apartment or condominium blocks) in some areas of the city now zoned for single-family houses only.

These are only a few of the possible options that can be fruitfully pursued.

If we really want to do this, and if we gather all resources and stakeholders together, we should be able to provide more affordable housing in Portland while keeping it the kind of place where we all want to live.