Cas Reservoir Inlet Between Lf And
Valley County, IdahoView mapDirections
Nutrients and algae run above the regional average.
↓ down from C at the last regrade
- Eutrophic
- #5 of 9 in the county
- Public access
Cas Reservoir Inlet Between Lf And in Valley County, Idaho has a water quality grade of D (Nutrient-rich). Water clarity: 4.3 ft visibility. Phosphorus: 40 µg/L. Chlorophyll-a (algae): 12.4 µg/L.
- Clarity
- 4.3 ft
- Type
- Eutrophic
- Phosphorus
- 40 µg/L
- Chlorophyll-a
- 12.4 µg/L
- Trend
- ↑ Improving
- Public access
- Yes
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Stays near Cas Reservoir Inlet Between Lf And
Compare lakeside cabins, hotels, and vacation rentals near Cas Reservoir Inlet Between Lf And in Valley County, Idaho — 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. The water-quality grade measures nutrients and algae, not lodging — cabins and rentals around Cas Reservoir Inlet Between Lf And are listed below.
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Cas Reservoir Inlet Between Lf And is a productive, nutrient-rich eutrophic lake in Valley County, Idaho. Water quality is graded D based on 2 sampling years through 2022. Overall water quality is improving over recent sampling years. Limited fish-species data available. Public access is available with 1 public boat landing. Compared to the 8 other monitored lakes in Valley County, Cas Reservoir Inlet Between Lf And ranks #5 for water quality.
Source: EPA Water Quality Portal sampling records, IDEQ, last sampled 2022-09-22. Grade methodology: LakeQuality methodology.
What Cas Reservoir Inlet Between Lf And is good for
From access and monitoring records, not editorial picks.
- Boat launch1 documented ramp
Swimming Safety
Grade onlyElevated nutrients
Based on clarity and algae grades from past sampling — we do not hold live water temperature and a current cyanobacteria reading for this lake. Check your state or county health department before you swim.
The D is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
Water Quality Grade: D (Nutrient-rich)
Murky, only visible to about 4.3 ft. Phosphorus 40 µg/L. Chlorophyll-a 12.4 µg/L. TSI 56. The letter is not a swimming clearance.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 4.3 ft | Not graded |
| Phosphorus | 40 µg/L | Fair |
| Chlorophyll-a (Algae) | 12.4 µg/L | Poor |
| Trophic State Index (TSI) | 56 | Eutrophic |
High nutrients, frequent algae, reduced clarity
Recreation & Access
- ButtercupPublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Cas Reservoir Inlet Between Lf And
Water Quality Trend: ↑ Improving
Based on 6 years of monitoring data (2020-2025).
| Metric | Trend | Change/Year | Years |
|---|---|---|---|
| Water Clarity | ↑ Improving | +0.056 m/yr | 6 |
| Phosphorus | ↑ Improving | -2.11 µg/L/yr | 6 |
| Chlorophyll-a | → Stable | +0.07 µg/L/yr | 6 |
County Ranking
Ranked #5 of 9 lakes in Valley County
Nearby Lakes in Valley County
Frequently asked questions about Cas Reservoir Inlet Between Lf And
Where is Cas Reservoir Inlet Between Lf And?
- Cas Reservoir Inlet Between Lf And is a lake in Valley County, Idaho. LakeQuality grades it D for nutrients and algae. The letter is not a swimming clearance.
What is the water quality grade for Cas Reservoir Inlet Between Lf And?
- Cas Reservoir Inlet Between Lf And in Valley County, Idaho has a water quality grade of D (Nutrient-rich). Water clarity: 4.3 ft visibility. Phosphorus: 40 µg/L. Chlorophyll-a (algae): 12.4 µg/L.
Is Cas Reservoir Inlet Between Lf And safe to swim in?
- The D is nutrients and algae, not a swimming clearance. Check local advisories before you swim.
Are there boat ramps on Cas Reservoir Inlet Between Lf And?
- Cas Reservoir Inlet Between Lf And has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Buttercup. Public access is listed as yes.
Explore Cas Reservoir Inlet Between Lf And across LakeQuality
4 thermal springs within 7.7 mi, nearest Arling Hot Spring
Species activity outlook by water temperature and season
Where to stay at Idaho's top lakes, each with its grade
High nutrients, frequent algae, reduced clarity
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Where this data comes from
51 measurements from 1 monitoring station, 2012–2022. Retrieved from the EPA Water Quality Portal on 2026-08-02.
Collected and reported by
- Bureau of Reclamation
1119USBR_WQX51 samples · 2012–2022
Analytical methods
- Depth, Secchi disk depth
- Zebra/Quagga Mussel APHA 10200G Modified
- Phosphorus by Single Reagent Colorimetry
- 10200 H ~ Chlorophyll a-b-c Determination
- Turbidity by Nephelometry
Monitoring station identifiers (1)
Grade thresholds from the EPA National Lakes Assessment (EPA 841-R-24-006, Table 6-3), applied by ecoregion. See how grades are calculated and data sources.
Other records on this page
Named boat-access points from the USGS National Boat Ramps inventory