2022 AIA Communities by Design Reimagining Petaluma SDAT - Report - Page 22
Petaluma DAT
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entity released an analysis in 2021, that demonstrated
that low-income neighborhoods and communities of
color have significantly less tree canopy. Those areas
also are more likely to suffer from the urban heat island
effect caused by a lack of shade and an abundance of
heat-absorbing asphalt. Heat islands can be 10 degrees
hotter than surrounding neighborhoods. As climate
change continues to exacerbate heat in cities, people
are realizing that trees are indeed critical infrastructure.
The adjacent Petaluma map illustrates areas where the
urban heat island effect is critical. Tree planting should
be prioritized in these areas.
Trees are especially unique in that they appreciate in
value and capacity to perform, rather than depreciate,
over time. The older and bigger a tree gets the better it
is able to perform its job.
Adopt Sustainable Strategies for
Development
Stewardship of natural resources includes preservation
and rehabilitation of ecological processes such as
groundwater recharge, pollutant sequestration,
pollination services, and nutrient sequestration.
California is already experiencing the effects of climate
change, including warming temperatures, rising sea
levels, longer fire seasons and shifts in precipitation.
Wetlands – coastal, riparian, seasonal, or tidal – all
stand to suffer some of the greatest and most immediate
and noticeable impacts. The projected changes of
greatest concern are sea level rise, salinity shifts,
temperature increases, and an increase in the severity of
storms
Landscaping to reduce water use can be helpful to
greatly decrease the amount of water put on planted
areas. Xeriscaping is the process of planting with
native drought tolerant species that are adapted to the
region’s climate, which demand much less water to
survive and still preserve a beautiful aesthetic. When
watering the lawn or garden short cycles are more water
efficient than on long period, this gives plants and the
soil enough time to properly absorb water rather than
having small standing pools. Another method to reduce
water waste in the planted landscape is to create rain
gardens to capture runoff and restore soil moisture and
groundwater.
Implement waterwise strategies, such as:
• Avoiding any increase in impervious surface cover
and contaminated stormwater runoff, helping
protect watersheds, recharge groundwater, and
mitigate climate change.
• Conducting soil testing to determine soil quality
and composition. Lab testing is offered by many
university extension offices. When more is known
about the soil, then appropriate amendments can
be added.
• Ensuring soil is healthy. Healthy soil amended
with organic matter such as compost and other
nutrients helps plants retain moisture and resist
evaporation. Healthy soil also happens to be one of
the earth’s largest carbon sinks. Once soil is dried
out and depleted of nutrients, flood and erosion
risks increase and the many benefits of healthy soils
are lost.
• Incorporating mulch, which slows down evaporation
and protects plant roots from high and low
temperatures. Organic mulches absorb moisture
and retain it longer than soil that has not been
mulched. Place mulch over the soil around
plants (leaving some space around the trunk) to
reduce evaporation, limit heat stress, and inhibit
weed growth. Organic mulches include compost,
shredded bark, leaves, and sawdust.
• Reducing compaction without tilling: Aerators can
be used to reduce soil compaction without tilling,
which causes erosion, evaporation, and greenhouse
gas release from soil
