Each individual commercial developer will also be required to use onsite initiatives to help achieve the overall stormwater objectives by using rooftop storage which will also increase evaporation, spray irrigation which promotes evaporation and infiltration, and storage within the parking lots which will add storage and promote evaporation. In addition, several products are being explored, including the use of permeable pavement which will provide some onsite storage, as well as promote infiltration underneath the pavement structure.
This new commercial development in the City of Calgary falls within the West Nose Creek catchment area. New stormwater management regulations in this catchment require that both pre-development flows and volumes be maintained. While it is standard to have flows restricted to pre-development rates, Jacksonport will be one of the first projects in the City that will have restrictions on volume.
In this catchment only 90 mm of the 300 mm or so, of average rainfall will be permitted to be released to Nose Creek. This means that the water must be disposed of by some other means, including evaporation, infiltration, or reuse. In order to achieve this overall objective, a spray irrigation system will be incorporated into the design of the subdivision to promote evaporation and infiltration. In addition, evaporation from the pond will be accounted for in the storm system design. Water from the individual lots will be directed to bioswales that will then be directed to the stormwater facility.
