Heavenly at Lake Tahoe has installed some heavy duty stormwater treatment capability to protect receiving waters from polluted runoff generated in parking lot areas…
Heavenly Mountain Resort Blog » Blog Archive » Keeping Tahoe Blue
To mitigate damage to the clarity of Lake Tahoe, four large filtration vaults under the parking lot will purify runoff from the 15 acre facility. “The goal is to meet stormwater discharge standards,” Michelle says, “which are really stringent.” The filtration is accomplished by 428 ZPG filter cartridges which strain out sediment, chemicals that can pollute the downstream flow of Bijou Creek and damage the clarity of Lake Tahoe. These filters use zeolite, perlite, and granular activated carbon to remove Nitrogen, phosphorous, suspended and dissolved solids turbidity and sediment from the parking lot runoff.
The System is designed to handle a 20-year 1-hour storm event as required by the Tahoe Regional Planning agency and the Lahontan Regional Water Quality Control Board. The system can handle a 15 cubic foot per second flow, or the equivalent of 1 inch per hour. Any excess flows will be diverted around the system.
Each filter sits on a hole in the bottom of the vault which leads to the discharge duct. Runoff from the lot enters the vault and fills it up until water pressure activates a siphon effect within the cartridges. Water enters the filter media from the bottom and is drawn up to the top where clean water drains through a tube and out through the floor. The filters cost $250 to replace and can last up to seven years.
It’s neat to see a ski resort taking responsibility for the stormwater pollution generated by its activities and those of their visitors. These guys are trying their hardest to meet the high expectations of their patrons with investments in low-emission snow groomers and higher efficiency snow making equipment.
For those who wish their local hill would take on these type of projects, remember that Heavenly has 30 lifts and can service more than 50,000 skiers per hour – this is the largest hill in California.