I was sent this link to an outstanding piece of work done done Mid-Ohio Regional Planning Commission. This is a guide on how to do dense design right and why it matters:
I am just posting the link as the file is 2.5 MB.
Density, done right, is a result of good principles and planning that can provide our daily needs and amenities efficiently without appearing cluttered or feeling crowded.
Sprawl has costs. When houses are further apart on larger lots, they require longer stretches of road pavement than are needed to serve the same number of households on a denser street. Likewise, it requires more tax dollars to build and maintain sewer and water lines, and greater cost for private gas, electric and other utility lines. Those same factors increase the distance
to schools, stores and other amenities. They also increase development costs – and therefore the price of homes. Suburban and township governments grow to accommodate the service needs of new housing and population, while old central city governments still have
the same land area to serve, but with less population and revenue. Current patterns of development add to the size and cost of government. They also lead to loss of farmland: Land that is easiest to develop also tends to be land that is most productive in growing food.
Just as sprawl has many drawbacks, density has benefits. It allows compact and efficient use of land; efficient delivery of services; ease of travel on foot; and vibrant activity. It can draw a community together rather than push people apart.
I would add that perhaps the biggest cost of sprawl is actually public safety. These facilities are built and located based on response times and a 10 acre lot really does consume 100 times more response area than a 0.1 acre lot.