Castaic Lagoon
Castaic Lagoon in Los Angeles County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 165 acres.
- Area
- 165 acres
- Public access
- Yes
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Why Castaic Lagoon has no grade
We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Castaic Lagoon, no water-quality sampling on record for this lake.
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by your state environmental agency and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Castaic Lagoon is a 165-acre lake in Los Angeles County, California. Limited fish-species data available. Public access is available with 3 public boat landings.
Source: EPA Water Quality Portal sampling records, your state environmental agency, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Castaic Lagoon water quality
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Swimming Safety
Not ratedElevated nutrients
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Castaic Lagoon
These readings exist but are not enough for an A–F grade — see why.
No clarity data. Trophic State Index: undefined.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) |
Where to stay near Castaic Lagoon
Compare lakeside cabins, hotels, and vacation rentals near Castaic Lagoon in Los Angeles County, California — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Castaic Lagoon
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 165 acres |
| Public Access | Yes |
No bathymetric survey has been published for Castaic Lagoon, so its depth is not documented here.
Recreation & Access
- Castaic Lake OverlookPublic
- Castaic Lake State Recreation Area (Lagoon)Public
- CSU Northridge Aquatic CenterSemi-private
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Castaic Lagoon
Nearby Lakes in Los Angeles County
Frequently asked questions about Castaic Lagoon
Where is Castaic Lagoon?
- Castaic Lagoon is a lake in Los Angeles County, California. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Castaic Lagoon?
- Castaic Lagoon in Los Angeles County, California is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 165 acres.
Is Castaic Lagoon safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Castaic Lagoon is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Are there boat ramps on Castaic Lagoon?
- Castaic Lagoon has 3 documented boat landings in the USGS National Boat Ramps inventory. Named access points include Castaic Lake Overlook, Castaic Lake State Recreation Area (Lagoon), CSU Northridge Aquatic Center. Public access is listed as yes.
Explore Castaic Lagoon across LakeQuality
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Where this data comes from
Measurements for Castaic Lagoon come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Named boat-access points from the USGS National Boat Ramps inventory