Occoquan Bay National Wildlife Refuge is a national wildlife refuge in Prince William County, Virginia. It sits roughly 2.0 km (1.2 mi) SE of Woodbridge.
The Occoquan Bay National Wildlife Refuge is a National Wildlife Refuge located where the Occoquan River meets the Potomac River in Woodbridge, Virginia, United States between Belmont Bay and Occoquan Bay. The 644-acre (2.61 km2) site, about half of which is wetlands, was a popular tourist spot known as Dawson Beach until the 1940s, after which it was used for military research by the U.S. Army's Harry Diamond Laboratories from the 1960s to the 1990s. When the land was purchased from the military, it was temporarily called the Marumsco National Wildlife Refuge. The refuge was formally established and renamed in 1998, and is now managed by the United States Fish and Wildlife Service as part of the Potomac River National Wildlife Refuge Complex.From the Wikipedia article “Occoquan Bay National Wildlife Refuge”, licensed under CC BY-SA 4.0.
Sunrise & sunset directions
At Occoquan Bay National Wildlife Refuge the sunrise point swings a long way through the year: about 59° (ENE) at the June solstice and 120° (ESE) in late December. Sunset moves from 302° (WNW) in June to 240° (WSW) in December, and the midday sun climbs to 75° in summer but only 28° in winter.
| Date | Sunrise | Azimuth | Sunset | Azimuth | Noon sun | Daylight |
|---|---|---|---|---|---|---|
| March equinox (Mar 20) | 7:13 AM | 90° E | 7:21 PM | 271° W | 51° | 12h 08m |
| June solstice (Jun 21) | 5:45 AM | 59° ENE | 8:38 PM | 302° WNW | 75° | 14h 52m |
| September equinox (Sep 22) | 6:57 AM | 89° E | 7:08 PM | 271° W | 52° | 12h 10m |
| December solstice (Dec 21) | 7:24 AM | 120° ESE | 4:52 PM | 240° WSW | 28° | 9h 28m |
Azimuth is measured clockwise from true north (90° = east, 270° = west). Computed for 2026; values change by less than a degree from year to year.
Golden hour & blue hour by month
Wildlife is most active in the first and last two hours of daylight — exactly when the light is warmest.
| Month (15th) | Blue hour starts | Sunrise | Golden hour ends | Golden hour starts | Sunset | Blue hour ends | Daylight |
|---|---|---|---|---|---|---|---|
| January | 6:57 AM | 7:26 AM | 8:06 AM | 4:31 PM | 5:12 PM | 5:41 PM | 9h 46m |
| February | 6:34 AM | 7:01 AM | 7:38 AM | 5:10 PM | 5:47 PM | 6:14 PM | 10h 46m |
| March | 6:55 AM | 7:21 AM | 7:56 AM | 6:41 PM | 7:16 PM | 7:43 PM | 11h 55m |
| April | 6:06 AM | 6:33 AM | 7:09 AM | 7:10 PM | 7:46 PM | 8:13 PM | 13h 12m |
| May | 5:28 AM | 5:58 AM | 6:36 AM | 7:37 PM | 8:14 PM | 8:44 PM | 14h 16m |
| June | 5:13 AM | 5:45 AM | 6:24 AM | 7:56 PM | 8:36 PM | 9:08 PM | 14h 51m |
| July | 5:26 AM | 5:57 AM | 6:36 AM | 7:55 PM | 8:34 PM | 9:05 PM | 14h 37m |
| August | 5:55 AM | 6:24 AM | 7:00 AM | 7:29 PM | 8:05 PM | 8:33 PM | 13h 41m |
| September | 6:25 AM | 6:51 AM | 7:26 AM | 6:44 PM | 7:19 PM | 7:46 PM | 12h 28m |
| October | 6:52 AM | 7:19 AM | 7:55 AM | 5:56 PM | 6:32 PM | 6:59 PM | 11h 14m |
| November | 6:23 AM | 6:52 AM | 7:31 AM | 4:18 PM | 4:57 PM | 5:25 PM | 10h 05m |
| December | 6:51 AM | 7:20 AM | 8:02 AM | 4:08 PM | 4:49 PM | 5:19 PM | 9h 29m |
Local time (America/New York), including daylight saving time. Golden hour runs from about −4° to +6° solar altitude, so the morning golden hour begins during blue hour, before sunrise.
Milky Way & night sky
From Occoquan Bay National Wildlife Refuge, the Milky Way core is visible in a dark sky from March through September. June gives the longest window (about 5.2 hours on a moonless night), and the core peaks around 22° above the southern horizon. Our light-pollution model puts the sky at about Bortle 7 (suburban / urban transition), so expect visible sky glow; drive away from towns for better results.
| Month | Core visible (15th) | Hours | Max altitude | Direction |
|---|---|---|---|---|
| January | Below 10° in darkness | — | -2° | — |
| February | 5:16 AM – 5:26 AM | 0.2 | 12° | SE → SE |
| March | 4:25 AM – 5:45 AM | 1.3 | 19° | SE → SSE |
| April | 2:21 AM – 4:51 AM | 2.5 | 22° | SE → S |
| May | 12:22 AM – 4:02 AM | 3.7 | 22° | SE → S |
| June | 10:34 PM – 3:44 AM | 5.2 | 22° | SE → SSW |
| July | 10:27 PM – 2:17 AM | 3.8 | 22° | SSE → SW |
| August | 9:44 PM – 12:14 AM | 2.5 | 22° | S → SW |
| September | 8:49 PM – 10:09 PM | 1.3 | 19° | SSW → SW |
| October | 8:01 PM – 8:21 PM | 0.3 | 12° | SW → SW |
| November | Below 10° in darkness | — | 0° | — |
| December | Below 10° in darkness | — | -19° | — |
Window when the galactic core is at least 10° high during astronomical darkness on the 15th of each month. Pick nights within a few days of the new moon. Plan exact nights with the Milky Way planner.
Estimated sky darkness: 7 Bortle 7 — Suburban / urban transition. The whole sky has a grey-white glow; the Milky Way is invisible to the eye. Modeled zenith brightness ≈ 18.83 mag/arcsec². Aurora needs roughly Kp 7.5+ to show low on the northern horizon here.
Weather & best season
Long-term NASA satellite data for this area show September as the clearest month (about 52% average cloud cover) and May as the cloudiest (61%). July is the warmest month and January the coldest, which matters for gear, snow access and how long batteries last at night.
Average cloud cover (%)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| High °F | 76 | 76 | 81 | 95 | 93 | 100 | 106 | 105 | 99 | 98 | 80 | 76 |
| Low °F | 2 | -2 | -1 | 23 | 32 | 45 | 52 | 54 | 41 | 28 | 20 | 8 |
| Precip. (in) | 2.5 | 2.9 | 3.1 | 3.7 | 4.7 | 4.7 | 4.1 | 3.9 | 4.3 | 3.8 | 3.2 | 3.4 |
Monthly climatology for the surrounding 1° grid cell from NASA POWER (MERRA-2). Mountain sites can be colder and cloudier than the cell average.
Photography tips for this national wildlife refuge
- Use auto-loop roads as mobile blinds; animals often tolerate vehicles more than people on foot.
- Stay on designated routes and keep a respectful distance — if an animal changes behavior, you are too close.
- A 400–600 mm lens (or a crop body) is the usual tool for birds.
- Fast shutter speeds (1/2000 s+) freeze wingbeats; raise ISO rather than lose the shot.
- Scout in daylight if you plan to shoot at night or before sunrise.
Season: Spring and autumn migration are the highlights; winter brings waterfowl to many southern refuges.
Suggested gear: Telephoto lens (400 mm+), Bean bag for car window, Binoculars. Work out exposures with the depth of field, ND filter and NPF rule calculators.
Permits, drones & access
Drones: Launching or landing drones on National Wildlife Refuge lands generally requires a special use permit from the refuge manager, and wildlife disturbance rules apply everywhere.
Nearby photo spots
Other locations within 40 km of Occoquan Bay National Wildlife Refuge, closest first.
State Park
National Wildlife Refuge
State Park
National Wildlife Refuge
State Park
State Park
Lighthouse
Botanical Garden
Scenic ViewpointCampgrounds nearby (Recreation.gov)
- Prince William Forest Rv Park11.0 km (6.8 mi)
- Telegraph Picnic Pavilion13.3 km (8.3 mi) · reservable
- Turkey Run Ridge Group13.8 km (8.6 mi) · reservable
- Cabin Camp 314.0 km (8.7 mi) · reservable
- Oak Ridge Campground16.2 km (10.1 mi) · reservable
FAQ
When is the best time to photograph Occoquan Bay National Wildlife Refuge?
What time is golden hour at Occoquan Bay National Wildlife Refuge?
Where does the sun rise and set at Occoquan Bay National Wildlife Refuge?
Can you see the Milky Way from Occoquan Bay National Wildlife Refuge?
Do you need a permit to photograph at Occoquan Bay National Wildlife Refuge?
How far is Occoquan Bay National Wildlife Refuge from Woodbridge?
Sources
Location data: Wikidata, Wikipedia. Sun, moon and Milky Way times are computed by LWPhoto Atlas for 2026. Climate: NASA POWER. Sky darkness is a population-based estimate (Walker's law), not a measurement. See data sources & licenses.