PlanITImpact Scores, explained…continued
Dominique Davison / January 23, 2017
As a continuation of the previous posting on PlanITImpact Score, we will be focusing on the Stormwater Impact Score and Water Use and Cost* next. This score is in response to the Pre-development condition overall site perviousness, vs the Post-development condition site perviousness. The goal is not to further burden the city’s infrastructure and encourage the integration of BMP’s into a project. PlanIT Impact recognizes that stormwater design is a complex business, better left to the civil engineers and again, every municipality has their own requirements and criteria. But the many experts we have interviewed agree that prioritizing and considering overall site perviousness early in the site design process, can help to alleviate future costs and complications.
A score of 50 for the Stormwater Impact Score means the site design matches the pre-development condition and a higher score reflects the percentage of increase in overall perviousness of the design.
This is a rather simple and straight forward score. However, when thinking about infill sites where the structure has been demolished, our team and the experts we have been working with in Beta, had to pause. Do we want to penalize a project with a lower score for building in an infill site that is currently vacant, if the infrastructure is already in place for a building or parking lot that once stood there? Many municipalities allow the last known developed condition to be the one that is set as the baseline, and we encourage users to use this approach as well. But what are your thoughts? Again, we appreciate input from our users and potential users, as we want PlanIT Impact to best serve your purpose.
Water use is based on the number of occupants for a specific project and the kinds of fixtures that are expected to be used within the facility. PlanIT Impact compares the EPA code minimum values for water flow and flush rates to what the expected water use values are for a project, calculating a percent improvement (or reduction) in water use as the score. As previously stated, a score of 50 is code minimum and a score of 100 equates to Net Zero water use.
Besides picking Water Sense fixtures, the user can manually adjust water flow rates to achieve greater levels of efficiency expected from such choices as waterless urinals, dual flush toilets or aerators on faucets. Water collection systems also offset the overall baseline water use and can greatly improve your score.
*Costs are estimated based on the inputs provided and PlanIT Impact makes no assertions as to their actual costs, and does not guarantee that a project will perform as estimated.