Talking Big: Lessons Learned from a 9000 Hectare Restoration in the Northern Tallgrass Prairie

Gerla, P. J., et al., 2012. Sustainability

Original research (primary data)
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Large tracts (>1000 ha) of prairie are essential to the sustainability of grassland ecosystem services, yet in many ecoregions only small fragments remain. Glacial Ridge is among the largest prairie-wetland restorations ever attempted. Started in 2000, the 9000 ha project in northwest Minnesota, USA, was initiated to reconnect 14 small tallgrass prairie remnants. In all, 15,200 ha of contiguous habitat comprise the project’s direct accomplishment. We created a partnership of more than 30 organizations, filled 177 km of drainage ditch, restored 1240 ha of wetland, and replanted 8100 ha. Flooding has been mitigated, water quality improved, and native vegetation reestablished. Animals not documented for decades have again occupied the site. Despite these accomplishments, the project would have been unnecessary if the land had been purchased in the 1970s, prior to conversion to agriculture, at one-tenth the restoration cost. Our challenges related to funding, differences in partners’ restoration philosophy, community concerns about floods and tax losses, difficulties in obtaining seed, and follow-up management of invasive weeds. We summarize the restoration process and share basic principles that will help others to develop large-scale prairie restoration projects in the future.

Case studies

Basic information

  • Case ID: INT-050-1
  • Intervention type: Restoration
  • Intervention description:

    The Glacial Ridge Project: reconnect a cluster of 14 fragmented prairie-wetland remnants (totaling 5200 ha) by restoring the habitat and hydrology of the 9000 ha core area; [actions involve] plugging (installing a clay “stopper” to prevent flow), filling, compacting, and re-grading previously excavated soil to the greatest extent possible; some of the ditches could not be entirely decommissioned and had to be either diked to restore adjacent wetlands or reconstructed to a more natural configuration while assuring adequate conveyance of runoff

  • Landscape/sea scape ecosystem management: Yes
  • Climate change impacts Effect of Nbs on CCI Effect measures
    Freshwater flooding  Positive groundwater recharge, surface-water runoff, discharge/flood peaks
  • Approach implemented in the field: Yes
  • Specific location:

    Glacial Ridge [in Minnesota] lies within the 250,000-ha Agassiz Beach Ridges landscape (Figure 1). The landscape straddles the eastern shorelines of glacial Lake Agassiz

  • Country: United States of America
  • Habitat/Biome type: Temperate grasslands | Wetlands |
  • Issue specific term: Not applicable


  • Notes on intervention effectivness: effectiveness compared to effects of climate impact before intervention was implemented Coded as not original assessment because most of the relevant outcome results here are derived from other data sources AND analyses, however, they bring them together to provide a novel analysis, therefore we included this study.
  • Is the assessment original?: No
  • Broadtype of intervention considered: Not applicable
  • Compare effectivness?: No
  • Compared to the non-NBS approach: Not applicable
  • Report greenhouse gas mitigation?: No
  • Impacts on GHG: Not applicable
  • Assess outcomes of the intervention on natural ecosystems: Yes
  • Impacts for the ecosystem: Positive
  • Ecosystem measures: percent cover of native species and native species richness of native graminoids and forbs
  • Assess outcomes of the intervention on people: Yes
  • Impacts for people: Positive
  • People measures: job creation
  • Considers economic costs: Yes
  • Economic appraisal conducted: No
  • Economic appraisal described:
  • Economic costs of alternative considered: No
  • Compared to an alternative: Not reported

Evaluation methodology

  • Type of data: Quantitative
  • Is it experimental: No
  • Experimental evalution done: Not applicable
  • Non-experimental evalution done: Empirical case study
  • Study is systematic: