Open Space subcommittee unveils draft GIS conservation-priority map, flags missing datasets

Michelle, the subcommittee intern who led the GIS work, presented a draft conservation-priority map to the Open Space Commission, saying the goal was “to give the commission and ultimately the city a datadriven spatially explicit picture of where conservation investment will have the greatest impact within Davis’s planning area.” She described a methodology that divides the planning area into 5‑acre hexagons, scores 13 attributes across eight categories (floodplains, creek proximity, conservation lands, farmland, sensitive‑species habitat and others), and sums results to show higher‑value hexagons on the map.

Michelle said the team has scored 10 of the 13 attributes so far and that, with those inputs, “the maximum theoretical total score is eight, and the maximum we’re observing is seven.” She identified three critical data gaps that remain: priority acquisition areas from the Yolo/Solano habitat conservancy listing, sensitive‑species data from the California Natural Diversity Database (CNDB), and a habitat land‑cover layer the consultant used in its presentation. She noted that some datasets are costly or require permission from multiple parties — citing a CNDB data fee she described as roughly $600 — and that those needs have delayed a final product.

Commissioners debated presentation choices and how to use the scores. One concern was that including already‑protected lands as a positive score component makes those areas look like high acquisition priorities, when in practice they are already conserved. Michelle said the underlying conservation‑value map intentionally mixes biological attributes and policy objectives, but commissioners asked for a separate analysis that excludes already‑protected parcels so decisionmakers can more easily identify new land to pursue. Several commissioners also requested zoomed‑in examples, clearer nontechnical language for public presentations, and an alternative visualization that outlines existing conserved land rather than fully overlaying it.

The presentation walked commissioners through technical scoring rules: most attributes are binary (presence/absence), three use graduated scoring (for example, floodplain categories), and creek proximity was scored for hexagons within roughly 30 meters of a creek centerline. Michelle said the highest‑scoring areas in the draft corresponded to creek corridors, floodplain areas and existing conservation lands — the patterns project authors expected — and that final scores could change when the three missing data layers are incorporated.

Commissioners and staff discussed next steps and timeline. Michelle asked to return with an updated map in roughly a month after integrating the missing datasets and supplying high‑resolution, zoomed examples for public explanation. The subcommittee also said it will coordinate with consultants, the conservancy and city GIS staff to secure the remaining layers and produce alternate visualizations (including separate “conservation‑value” and “priority‑acquisition” views).