Lake Arcadia Dam #1 Dam dam
Lake Arcadia Dam #1 Dam
Located in West Milford Township, New Jersey, the Lake Arcadia Dam #1 Dam is a concrete structure completed in 1926 for the primary purpose of recreation. With a height of 22 feet and a length of 315 feet, the dam impounds Bear Swamp Brook, creating a surface area of 86 acres and a maximum storage capacity of 1,000 acre-feet. Despite its recreational value, the dam is classified as having a significant hazard potential and is currently in poor condition, as assessed in October 2021.
Owned privately, the dam falls under the regulatory jurisdiction of the New Jersey Department of Environmental Protection (NJDEP), which oversees its permitting, inspection, and enforcement. Although the dam has not been modified in recent years and lacks certain safety features such as an emergency action plan (EAP) and inundation maps, it is subject to regular inspections every two years to ensure its structural integrity and public safety. Given its condition assessment and hazard potential, the Lake Arcadia Dam #1 Dam serves as a critical reminder of the importance of maintaining and monitoring aging infrastructure in the face of evolving climate conditions.
As a key feature of the Passaic County landscape, the Lake Arcadia Dam #1 Dam poses both opportunities for recreation and potential risks in the event of a failure. With its historical significance dating back nearly a century, the dam serves as a testament to the engineering achievements of the past while highlighting the ongoing challenges of managing water resources and climate impacts in the present day. As water resource and climate enthusiasts continue to monitor the state of dams like Lake Arcadia Dam #1, they play a vital role in promoting resilience and sustainability in the face of a changing environment.
Dam data reference
Condition Assessment
- Satisfactory
- No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
- Fair
- No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action.
- Poor
- A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency.
- Unsatisfactory
- A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
- Not Rated
- The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Hazard Potential Classification
- High
- Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
- Significant
- Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
- Low
- Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
- Undetermined
- Dams for which a downstream hazard potential has not been designated or is not provided.
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Lake Arcadia Dam #1 Dam -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| Pequannock R At Macopin Intake Dam Nj | 6 cfs | → |
| West Brook Near Wanaque Nj | 6 cfs | → |
| Wanaque R At Wanaque Nj | 13 cfs | → |
| Pequannock River At Riverdale Nj | 12 cfs | → |
| Ramapo River At Pompton Lakes Nj | 67 cfs | → |
| Pompton River At Pompton Plains Nj | 126 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Lake Arcadia Dam #1 Dam.
Boat launches
- North Corporate Drive 2, Riverdale
- Lakeside Avenue Pompton Lakes
- Greenwood Lake Turnpike Ringwood
- Ringwood-Ramapo Trail Ringwood
- Blue Lake Road Town Of Warwick
- Island Avenue Little Falls
Track Lake Arcadia Dam #1 Dam in the Snoflo app
Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.
About Lake Arcadia Dam #1 Dam
Where does the data for Lake Arcadia Dam #1 Dam come from?
Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.
What does the Significant hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card above for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this dam, set a threshold, and you'll get a push the moment conditions cross.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of Lake Arcadia Dam #1 Dam.