US lakes & pondsUS lakes & pondsSurface area: The USGS National Hydrography Dataset outline (NHD Permanent ID 128059052).
The red circle marks Gross Reservoir.
Towns and counties: U.S. Census Bureau boundaries overlaid on the USGS lake outline (Colorado: incorporated places touching the lake, otherwise the nearest one).
Official CPW pages. Rules and fees change; check before you go.
Built only from the data on this page: official access lists, OpenStreetMap beaches and trails, campground listings, state and USGS invasive-species records. We don't rate crowds or water quality.
Fish species listed for this water in the CPW Fishing Atlas: Brook trout, Brown trout, Cutbow trout, Kokanee, Lake trout, Rainbow trout, Snake River cutthroat trout, Splake, Tiger muskie.
Stocking: Sub-catchables and Warmwater
Source: Colorado Parks and Wildlife, Colorado Fishing Atlas record for Gross Reservoir (Boulder County, CPW water code 55043). Acreage here can differ slightly from our mapped outline.
Numbers on the map match the list at rightbelow.
Shoreline: USGS National Hydrography Dataset (NHD Waterbody, Permanent ID 128059052), public domain. State outline: U.S. Census Bureau TIGERweb. Points: OpenStreetMap boat ramps (no statewide agency ramp layer used) and OpenStreetMap boat ramps (ODbL). Interactive map: Leaflet with © OpenStreetMap contributors. Not for navigation.
We found 39 campgrounds and RV parks within 15 miles of Gross Reservoir, 1 of them within 5 miles. Distances are straight-line from the nearest point on the shoreline, so driving distance is longer.
Tent sites · Campfires allowed
RVs welcome · Tent sites · Toilets · Drinking water
RVs welcome
RVs welcome
RVs welcome
All campgrounds & RV parks in Colorado
Green tent icons on the lake map mark campgrounds near the shore, and the interactive map shows the closest 12. Amenities are listed only where a source records them; call or check the campground's website before you go, since seasons and rates change every year.
Campground data: Recreation.gov (RIDB) · OpenStreetMap contributors (ODbL). Pulled Oct 12, 2026.
The closest airport with scheduled passenger flights to Gross Reservoir, plus larger airports within about 150 miles:
Compare car rentals near this lake
Car rental links go to our partner Discover Cars; LakeRipple may earn a commission at no extra cost to you. Affiliate disclosure.
Airports with scheduled airline service from OurAirports (large and medium airports); larger airports are FAA large, medium and small hubs by FAA CY2025 enplanements ("major airport" = FAA large hub). Distances are straight-line from the lake's center, not driving distance; road routes are longer.
Live from the National Weather Service API for the lake's coordinates (39.9457, -105.3692). The nearest station may be several miles away. NWS forecast for Gross Reservoir. No live water-temperature sensor is shown because we haven't found a public one for this lake.
Based on solunar theory, an estimate. Major periods (about 2 hours) center on when the moon is directly overhead or underfoot; minor periods (about 1 hour) center on moonrise and moonset. The 0–100 activity score rises during those periods and gets a boost near sunrise and sunset and around the new and full moon. Weather, water temperature and pressure often matter more. Sun and moon times are calculated in your browser from the lake's coordinates with standard astronomy formulas, shown in MT (America/Denver), and accurate to within a few minutes.
1 public access site listed, 1 with a boat ramp or trailer launch.
| Site | Town | Owner | Type | Parking | Fee | Uses | Map |
|---|---|---|---|---|---|---|---|
| Gross Reservoir Boat Ramp | — | — | Boat ramp (OpenStreetMap) · Yes ramp | — | — | Boating | 39.9366, -105.3732 |
OpenStreetMap boat ramps (no statewide agency ramp layer used) and OpenStreetMap boat ramps (ODbL)
Fees, hours and rules change; confirm with the site owner before you go.
Gross Reservoir covers about 415 acres in Boulder, Colorado (Boulder County).
CPW Colorado Fishing Atlas lists Lake trout, Rainbow trout, Brook trout, Kokanee, Brown trout, Cutbow trout, Snake River cutthroat trout, Splake and Tiger muskie.
Yes. 1 public trailer launch is listed: Gross Reservoir Boat Ramp. Check posted fees and parking rules.
Yes. We list 39 campgrounds and RV parks within 15 miles, 1 of them within 5 miles.
Gross Reservoir touches Boulder in Boulder County, Colorado.
Know Gross Reservoir? Tell us about the launch, parking, where they're biting or anything a first-time visitor should know. Tips go privately to the LakeRipple editor; nothing is posted automatically. Helpful tips may be featured on this page (we'll use your first name only if you give one).
Straight-line distance between lake centers. All Colorado lakes & ponds · All waters in Boulder