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Mr. Michael Grochala May 19, 2016 Page 3 to impact the existing wetlands through inadvertent drainage and to ensure the alignment is compatible with the existing Wetland Management Corridor. OPTION 4: CENTRAL OUTFALL This option would align the new outlet along property lines through the center of the study area (Figure 8). Benefits of this option include splitting the maintenance corridor between two landowners and utilizing existing low ground in the study area. Disadvantages include the cost of acquiring easements in highly‐developable land, impacts to existing wetlands, and lack of adequate cover for the pipe in some locations. OPTION 5: MODIFIED CENTRAL OUTFALL This option further refines Option 4, using the central outlet location on Peltier Lake Drive, but adjusting the alignment to follow the edges of wetlands to avoid wetland impacts (Figure 9). OPTION 6: OPEN CHANNEL This option is based on Option 5, but rather than a 72‐inch underground pipe, this option replaces the pipeline with a two‐stage open channel along roughly the same alignment. This option would require a 100‐ft easement, rather than a 70‐ft easement for the pipe option, but has more long‐term flexibility. A channel can handle larger flows, provides additional stormwater detention, and creates a public amenity for the community. Option 6 also has the added benefit of allowing for flexibility with future development plans, as it would be less costly to realign a ditch than a pipe. Ultimately the preferred option would be either Option 5 or 6, with a central outfall location. This location would benefit the most parties and be the most flexible for future development. ENVISION ANALYSIS There are a number of different rating systems to determine how sustainable, or “green,” an infrastructure project will be. The Envision™ Rating System was developed by the Institute for Sustainable Infrastructure and Harvard University’s Zofnass Program for Sustainable Infrastructure. It is a free tool, developed to be a broad‐based rating system for the evaluation of all kinds of civil infrastructure projects. The Envision™ Rating System was used to evaluate a simplistic pipe option versus greenway alignment based on their overall contribution to the economic, environmental and social aspects of sustainability, or the triple bottom line. It provides a way to holistically view the two options and ensure that the ultimate project provides the maximum value to the residents of Lino Lakes, is sustainable, and is an effective use of funding. The pipe option was evaluated against the open channel option using the Envision™ Checklist (Table 1). The pipe option received a total of 67 points out of 128 for a score of 52% of the total possible points, while the channel option (Table 2) received a total of 95 out of 129 points for a score of 75% of the total possible points. From the triple bottom line standpoint, the channel option out performs the pipe option. It does so in all the categories: Quality of Life, Resource Allocation, Natural World and Climate. It particularly fairs well in the Natural World category by providing additional environmental benefits, but it also does better in the Quality of Life by enhancing public space opportunities for the residents of Lino Lakes. It also is a more resilient option in the face of shifting climate dynamics because the capacity of the system will not be limited by a single pipeline.