A Basin-Wide Analysis of Stormwater Flows, Low Impact Development (LID), and Groundwater Contributions
The Great Salt Lake Storm (GSL) Water Study was insightful on the volume metrics of stormwater flow to the GSL by comparing different forms of development in urban settings.
Specifically, Low Impact Development (LID) versus traditional non-ecological development and undeveloped lands. However, this siloed analysis fails to recognize the complexity of urban-ecological and climate systems and how ground water recharge positively affects the urban forestry. This narrow view focuses only on getting storm water from development to the GSL and ends up suggesting that Low Impact Development would be detrimental to saving the GSL. Yes, less storm water runoff makes it into the great salt lake when collected in bio swales which are designed to improve water quality and recharge ground water in comparison to impervious parking lots and roofs, this is ultimately advocating for more development with impervious surfaces as the savior of the great salt lake, to ensure all run off, polluted or not, runs into the GSL.
How could it be that LID is considered inferior to solving an ecological crisis regarding water? The truth is, it is not inferior. I notice this is not taking into account a spectrum of unacknowledged benefits to to the GSL watershed and the broader ecological system we are living in when utilizing LID. Ground water is what keeps our mature urban trees alive, reducing the urban heat island, reducing the amount of irrigation needed on our landscapes, reducing the amount of fossil fuels and electricity to keep our buildings air conditioned, and even helping to enable rain in the local area by increasing the humidity and cooling the environment.
Utilizing rain water to irrigate our urban settings through passive harvesting minimizes our water consumption for our landscapes, allowing for less water diversions upstream where the bulk of our water comes from. Mimicking the natural cycles of spreading and sinking the rainwater into the ground reduces our dependency on costly infrastructure in the first place, making our built environment more resilient. In addition, the GSL basin sees its summer rainstorms in monsoon fashion, meaning the rains comes in brief but heavy bursts. When LID is not practiced, water flashes off the impervious surfaces and is directed into our urban streams which already suffer from urban stream syndrome or channelized, eroded streams with harmed ecological function from draining urban land. This harms endemic plant and animal species such as the Bonneville Cutthroat Trout.
In short, this study is hopefully just one piece to a much larger review of our land and water management strategies in relation to preserving our GSL. It is critical to remember the complexities of our environment and how this study is real estate development bias, promotes business as usual, the development of undeveloped lands throughout the basin and how this will inform future land management and water policy strategy.
Vincent Gryboski – Landscape Designer, Urban Ecologist, Conservationist & Land Management Specialist
Watering Your Xeriscape
One of the main goals with an established and mature xeriscape is to water once or twice per Month. This depends on your native and waterwise plant selection, soil type and a well designed drip irrigation system. However, the first 2-3 years, xeriscapes need to be irrigated almost everyday in the peak of summer, to ensure they can handle the transplant shock, and to encourage deep root growth.
Once the xeriscape is established, start pulling back your watering frequency (1-2 times per month) but maintain the duration of watering (25-35 minutes). This allows the efficiency of the slow drip irrigation to provide the plants a deep watering and longer span of time between watering intervals.
