Richard Cargill: Mining the St. Vrain Valley enhances flood risk
POSTED: 09/01/2017 09:11:32 AM MDT
UPDATED: 09/01/2017 09:15:07 AM MDT
Flooding in the St. Vrain Valley is a natural phenomenon that has been occurring for tens of thousands of years.
I witnessed the flood of 2013 from my home across the valley on Hygiene Road. I heard the roar of the river and watched it destroy ponds that were left from mining. Near 61st and Hygiene Road, the river jumped its track, destroying more mining ponds, and it swept that water east with great force. When the water breached the mining ponds at Pella Crossing, there was a massive swell of water and debris crashing into unsuspecting neighborhoods in Longmont.
The 2014 St.Vrain Creek Watershed Master Plan states, “During the flood, large split flow paths cascaded through the reclaimed gravel mining ponds. One split channel resulted in flooding outside of the 100-year floodplain and affected neighborhoods downstream in the City of Longmont. … Although the adjacent floodplain has been historically connected to the channel, sand and gravel mining operations have altered the natural floodplain function for a majority of this reach.”
If you go to Pella Crossing, 61st or Hygiene Road, you can see how the power of the floodwater blew out the mining ponds, adding to the catastrophe. The devastation is evidence of the knowledge that mining ponds should not be on a floodplain.
But, Martin Marietta Materials intends to mine between Hygiene Road and Colo. 66. Mining will leave behind even more mining ponds. Shouldn’t the valley’s floodplain be left alone? The valley is appropriate for open space, recreation and agriculture.
Make your voice heard. Email firstname.lastname@example.org, and Eric Lane, director of Parks and Open Space, email@example.com. Ask them to say no to Martin Marietta Materials’ intention to mine more than 400 acres in the St. Vrain floodplain. Together we can help avert future flooding in Longmont.
Letter to the Editor published in the Times Call on September 1, 2017.