Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Klum Lake IA 01-NEM-66

Louisa County S25T75NR2W 2 mi. ESE of Grandview.

Cycle
2016
Release Status
Final
Overall IR
4 - Water is impaired or threatened and a TMDL has been completed or is not needed.
Trend
Unknown
Created
8/23/2016 9:53:40 AM
Updated
8/23/2016 10:28:39 AM
Use Support
Class BLW
Aquatic Life - Lakes and wetlands
Partially Supported
Support Level
Partially Supported
Impairment Code
4c - Non-pollutant caused impairment. No TMDL needed.
Cause Magnitude
Moderate
Status
Continuing
Source
Hydromodification
Source Confidence
Moderate
Cycle Added
1998
Impairment Rationale
Adverse impacts on plant/animal communities
Data Source
Biological monitoring: Iowa DNR Wildlife
Class HH
Human Health -
Not Assessed
General Use
General Use water -
Not Assessed
Impairment Delistings
No delistings for this assessment cycle.
Documentation
Assessment Summary

Continue to assess (evaluate) support of the Class B(LW) aquatic life uses as "partially supported" due to hydrological modifications (flow alterations) that affect this wetland. This type of impairment is appropriate for Category 4c of Iowa's Integrated Report (i.e., impairment due to a non-pollutant stressor). Fish consumption uses remain "not assessed" due to the lack of fish contaminant monitoring in this wetland. This assessment is the same as that developed for previous assessment/listing cycles.

Assessment Explanation

According to the local DNR Wildlife Biologist, this wetland is not impaired by excess nutrients from agricultural lands.   Impacts from hydrological modification, however, continue.   This wetland lies in a levee and drainage district, and the main drainage ditch is adjacent to the wetland basin.   Deepening of the ditch and increased pumping back in the late 1960's or early 1970's completely altered Klum Lake from a mostly open semi-permanent wetland to a seasonal wetland dominated by thick stands of perennial emergent vegetation.   Water is pumped into the basin in the fall for migratory waterfowl use, but this pumping does not remedy the problem.   The impacts from hydrological modification at this wetland are similar to those at Allen Green Refuge Marsh.   Pumping sufficient water to maintain previous wetland conditions at either wetland is not possible given (1) summer evaporation and transpiration rates, (2) current pumping capabilities, and (3) the cost of such pumping.  

Fish consumption uses remain "not assessed."  In general, Iowa wetlands are not managed for recreational fisheries; thus, fish contaminant monitoring is not typically conducted at these waterbodies.

Monitoring and Methods
Assessment Key Dates

None listed

Methods
120
Surveys of fish and game biologists/other professionals