Highlight • Lake
Gross Reservoir
Running
5.0
(1)
Hiking
5.0
(1)
Gross Reservoir is a prominent man-made lake nestled in Boulder County, Colorado, serving as a vital water storage facility for Denver Water. Situated at an elevation where its spillway sits at 7,225 feet (2,202 meters), this expansive body of water is a significant landmark in the Front Range of the Rocky Mountains, easily accessible from both Boulder and the Denver metropolitan area.
Visitors consistently praise Gross Reservoir for its diverse outdoor opportunities and tranquil setting. Many enjoy utilizing the scenic picnic areas, observing local wildlife, and fishing for various species such as rainbow, brown, and lake trout, as well as Kokanee salmon and tiger muskie. The unique, transformed landscape, especially visible when exploring trails like the one leading into Forsythe Canyon, offers a distinct natural experience.
Before heading out, it's helpful to know that Gross Reservoir is undergoing a significant expansion project, which may affect access and water levels. While the north side generally remains open, visitors should anticipate a more primitive outdoor experience with limited amenities. Access is primarily via Gross Dam Road, which can be reached from Highway 93 and 72, or Flagstaff Road from Boulder. Parking at Gross Reservoir lake trailheads is available, though it's wise to check for any current restrictions.
The reservoir offers a range of activities throughout the year, from hiking on designated trails to non-motorized boating like canoeing, kayaking, and paddleboarding. Fishing, including ice fishing in colder months, is a popular pastime. While swimming, wading, and cliff jumping are prohibited to protect water quality, the area provides ample opportunities for those seeking a rugged natural environment. For those interested in winter hiking, Gross Reservoir lake options are available, though conditions should always be checked.
Many hikers describe the trail into Forsythe Canyon as packed, flowing, and nontechnical, leading alongside the creek before opening up to the reservoir's bed. This allows for a unique exploration of the shoreline. The chance to spot diverse wildlife or successfully catch one of the stocked fish adds to the memorable experiences here.
Whether you're looking for family-friendly activities at Gross Reservoir lake or seeking a challenging hike, komoot offers a variety of routes to help you plan your visit. From scenic viewpoints to trails suitable for beginner hiking, there are numerous ways to explore this remarkable Colorado destination.
This Highlight is in a protected area
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Tips
August 8, 2023
Hiking
This is an amazing spot to utilize the picnic areas, watch wildlife, and snag one of the trout, salmon, or muskie that are stocked here.
November 12, 2023
Running
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Nearby routes
Best routes near Gross Reservoir
5.0
(2)
52
hikers
3.89km
01:07
100m
100m
Hike the moderate 2.4-mile Forsythe Canyon Trail through a shaded canyon to a seasonal waterfall and the scenic Gross Reservoir.
Details
Informations
Elevation 2,230 m
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Max wind speed: 23.0 km/h
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Frequently Asked Questions
What are the best hiking trails for different skill levels at Gross Reservoir?
Gross Reservoir offers a variety of trails. The trail into Forsythe Canyon is often described as packed, flowing, and nontechnical, making it suitable for many hikers. It follows the creek and opens up to the reservoir's bed, offering a unique landscape to explore. For those seeking more challenging options, other designated trails around the reservoir provide varying terrain and distances. While the north side generally remains open, it's always good to check for current access restrictions due to the expansion project.
Are there easy hiking options for beginners or families with young children?
Yes, the trail into Forsythe Canyon is considered nontechnical and relatively easy, making it a good option for beginners and families. It's a pleasant walk alongside the creek. The area is generally family-friendly, with picnic areas available. However, be aware that the overall experience is more primitive, with limited amenities.
What should I know about parking at Gross Reservoir, especially during the expansion project?
Parking at Gross Reservoir lake trailheads is available, but it's crucial to be aware of potential restrictions due to the ongoing expansion project. While the north side typically remains open, specific parking areas might be affected. It's advisable to check for current conditions before your visit. Arriving earlier in the day, especially on weekends, can help secure a spot.
Are permits or fees required to visit Gross Reservoir?
No, there are generally no permits or fees required for general access to Gross Reservoir for activities like hiking, fishing, or non-motorized boating. However, specific regulations apply to activities like dispersed camping, and it's always wise to check with Denver Water or local authorities for any updated rules or restrictions, especially concerning the ongoing expansion project.
Is Gross Reservoir dog-friendly, and what are the rules for pets?
Gross Reservoir is generally dog-friendly, allowing visitors to bring their canine companions. However, dogs must be kept on a leash at all times to protect wildlife and ensure the safety and enjoyment of all visitors. Please remember to clean up after your pet to maintain the natural environment.
What are the best times of year to visit Gross Reservoir, considering weather and water levels?
Gross Reservoir offers activities year-round. Spring and fall provide pleasant temperatures for hiking and fishing, often with beautiful foliage or blooming wildflowers. Summer is popular but can be crowded, and water levels might be lower due to the expansion project. Winter offers opportunities for ice fishing and snowshoeing, but conditions can be challenging, so always check the weather forecast and road conditions before heading out. The expansion project may impact water levels and access at any time of year.
What kind of wildlife can I expect to see at Gross Reservoir?
Gross Reservoir is a great spot for wildlife viewing. Visitors often report seeing various bird species, including waterfowl and raptors. Mammals such as deer, elk, and smaller creatures like squirrels and chipmunks are also common. The reservoir's diverse ecosystem provides habitats for a range of animals, making it an excellent location for nature observation.
Are there any amenities like restrooms, cafes, or accommodation near Gross Reservoir?
Gross Reservoir offers a more primitive outdoor experience with relatively few amenities directly on-site. There are picnic areas, but you should expect limited facilities like restrooms. There are no cafes or pubs immediately adjacent to the reservoir. For accommodation or more extensive services, you would need to travel to nearby towns like Boulder or Nederland, which are a short drive away.
Can I swim or wade in Gross Reservoir?
No, swimming, wading, and cliff jumping are strictly prohibited at Gross Reservoir. These restrictions are in place to protect water quality, as the reservoir serves as a vital part of Denver Water's system. While non-motorized boating like canoeing, kayaking, and paddleboarding is permitted, direct water contact activities are not allowed.
What is the current status of the Gross Reservoir expansion project, and how does it affect visitors?
The Gross Reservoir expansion project, which began in April 2022, is ongoing and aims to raise the dam by 131 feet. This significant construction will continue until around 2027. While the north side of the reservoir generally remains open to the public, visitors should anticipate lower water levels, some access restrictions, and potential construction noise or activity. It's always recommended to check Denver Water's official website for the most up-to-date information on closures or impacts before planning your visit.