Water quality and flood repairs

Section GE 3.01 of the Boulder County Comprehensive Plan [PDF] reads, “The county shall render land use decisions consistent with the preservation or improvement of groundwater quality as well as the conservation of groundwater supplies.” Residents in the area consider well water precious, and we reject water delivery by trucks or other means as a reasonable alternative for its permanent loss due to mining operations. Our page on the effects of gravel mining on groundwater addresses specifically how residents’ wells may be seriously impacted by the proposed mining operation near Hygiene. Previous surface mining in the valley lowered the water table, and permanently dried up an artesian spring and well on a neighboring property. Aside from affecting the supply of well water, there is also a risk that exposing the top of the aquifer may cause contamination to our groundwater. One example is that a spill could contaminate the underground water without the overlaying soil protection to filter the chemicals or contaminants. This is described in a 2011 study for the Municipal District of Peace in Alberta, Canada [PDF] (16).

2013 flood’s effects and need for repairs

Our Water page includes a photo of a private pond in the vicinity of the planned mining operation, which illustrates that the water table has not recovered following the 2013 flood. Restoration of the water table and flood damage need to be repaired prior to permitting additional mining activities that may add insult to injury.

Boulder County Comprehensive Plan (BCCP) addresses various land use issues, and includes information relevant to this proposed mining project. Links to the numerous maps in the plan are also provided on the BCCP website. The BCCP Geologic Hazard and Constraint Areas Map designates the majority of the proposed mining area as a Moderate Hazard Area. “Geologic Hazard Area,” with a “Moderate” risk of flooding. The Geology Element of the plan states, “Moderate Hazard Area shall mean that area, or those areas, as shown on the Geologic Hazards and Constraint Areas Map where geologic conditions are such that significant geotechnical problems exist and there is provisional risk related to intensive land uses” (Geology [GE] – Page 1). Notably, GE 1.02 states: “The county shall discourage intensive uses in Moderate Hazard Areas.” 

The 2014 St. Vrain Creek Watershed Master Plan [PDF] contains recommendations for restoration of the area, which is designated as Reach 3. It states, “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” (7-8). As noted on our environment overview page, this plan describes how the large split flow paths that formed during the flood resulted in flooding damage downstream in Longmont, outside of the 100-year floodplain. The 30% Design Report, St. Vrain Creek Restoration, Highway 36 to Crane Hollow Road [PDF] report (prepared for Boulder County Parks and Open Space) addresses the specific repairs for this reach in detail. It notes, “A comprehensive restoration for the entire reach is necessary, incorporating the individual restoration efforts of individual projects through the reach, to provide a single holistic restoration approach for the entire reach” (2). Regarding mining areas, the watershed plan asserts that any flood repair work should be coordinated with mining activities to promote flood risk reduction and habitat enhancement (7-9). Is this happening, and if so, what form is this coordination taking?

Post-flood reassessment needed

In September 2013, the St. Vrain Creek experienced the most devastating flood ever documented.  A wall of water flowed down the mountains, lifting houses off their foundations, destroying riparian habitat, causing above ground gasoline tanks to bob in the water, breaching man-made ponds, and contributing at least four fatalities along the Front Range. More than 1,600 people were evacuated, 1,200 homes destroyed and damaged, and 900 square miles impacted by flooding in the region.  This destruction was aggravated by the man-made changes to the watershed that preceded the flood event. For example, the watershed was dramatically altered by previous gravel and other mining activities immediately adjacent to the St. Vrain. The earlier gravel mines failed to reclaim the land and instead left behind numerous ponds that added to the floodwaters when they were breached by the mighty river, thus exacerbating the destruction.

In its current webpage regarding flood resiliency, the Boulder County Commissioners offer the following statement:

Local governments such as Boulder County have a responsibility to regulate development in the floodplain or else we may jeopardize the ability for everyone in our jurisdiction to obtain flood insurance. Boulder County is taking a thoughtful and cautious approach to rebuilding. We need to understand the long-term implications of decisions we make today and how they will impact and inform the outcome of the next disaster. The county is working diligently to assess the future hazards and make informed decisions that will provide the base for further activities in recovery. People’s lives have been turned upside-down by this event. Boulder County is working with the community to balance the need to rebuild with the need to plan wisely for the next natural disaster.

When it comes to major construction projects in the watershed, the 2013 flood changed everything. Unfortunately, we see little evidence that the County is “regulating [this] development in the floodplain”, “is taking a thoughtful and cautious approach to rebuilding”, or “understands the long-term implications of decisions we make today and how they will impact and inform the outcome of the next disaster.” Instead, the County appears to be proceeding as though the flood never happened by approving this project for mining on over 800 acres of agricultural land, all of which was in the 2013 floodplain. The County is poised to approve a massive mining project similar to previous ones that exacerbated the destruction of the watershed–even causing flooding in areas in Longmont outside the floodplain.

On April 11, 2018 the County ruled that the permit had not lapsed due to inactivity and this decision was very narrowly upheld by Board of Adjustment appeal hearing. SOSvv is considering its response. Regardless of next steps, the County should use its inherent public health and safety powers to completely reexamine all outdated approvals associated with this mining project. Simply put, it is not 1998 any more. Thus, the County may not rely on decades-old approvals as though the flood never occurred. The project proposes more ground disturbance, more ponded water, more impacts to riparian and wetland habitat—all of which could exacerbate future flooding events. The County must scientifically assess how this project will impact future flood events and whether such a project should be allowed to proceed in light of the knowledge we now possess.  We urge the County to use caution and common sense and to re-assess all approvals for this project in light of the 2013 flood.  The lives of the citizens living in the St. Vrain Valley depend upon it.