5.9 Summary

The following tables summarize the proposed implementation action items and their relationship to the problems and issues identified in section 3.0 above, the metrics by which the District will be evaluating progress toward resolving hose issues and problems, the estimated District cost of implementing those actions, and anticipated implementation schedule.

Table 14.  Problems and issues identified in the Christmas lake subwatershed and actions proposed to address them.

 

Problem or Issue

Actions in Implementation Plan

Degree of Improvement

Water Quality

The water quality in Christmas Lake scores in the A grade range and nearly meets its TP concentration goal of 15 μg/L.  

  • A phosphorus load reduction plan for Christmas Lake that sets forth actions to maintain or reduce loading to maintain or improve in-lake P concentration goals.  These actions include LGU requirements to reduce phosphorus from existing development, and regulatory requirements to minimize load from new developments.
  • Continue monitoring Christmas Lake to evaluate trends in water quality. 

Implementation of all the actions in the phosphorus load reduction plan would protect existing water quality.

 

There is a very slow trend of increasing phosphorus and declining water quality in Christmas Lake.

  • A study to better understand lake hydrology and water quality and diagnose potential causes of the trend.
  • Would depend on outcome of the study.
  • Identification and stabilization of erosion on the shoreline and channels conveying stormwater to the lake to reduce those potential sources of pollutants.
 
 

Development and redevelopment in the subwatershed will increase nutrient and TSS loads from the watershed as well as increasing the volume of stormwater runoff.

Rules will be amended to add a volume management requirement on new development and redevelopment to reduce pollutant transport

Would depend on ability of developers to incorporate adequate BMPs on their projects and properly maintain them to sustain removal efficiencies.

The HHPLS identified sediment accumulation and transport in the small channel that discharges into the south end of the lake. 

  • Staff will periodically inspect the channel for erosion
  • District will consider a cooperative project with LGU to stabilize channel

Depends on extent of problem and ability to develop cooperative or collaborative improvements.

Water Quantity

Steep slopes in east shore of lake are erosion prone. 

  • District will inventory the shoreline to determine extent of erosion area.
  • Education program will target message to shoreline owners about shoreline stabilization.
  • District will consider small grant program to assist property owners in shoreline stabilization

Would depend on homeowner willingness to perform improvements.

Landlocked subwatersheds and basins are present.

  • LGUs prohibited from outletting these landlocked areas unless there is a threat to property, structures or public safety, and directed to evaluate strategies for managing water volumes as part of their local water management planning.

Completed as LGUs complete their local plans.

Development, redevelopment, and reconstruction in the subwatershed, is predicted to increase volume of stormwater runoff from the watershed as well as increased nutrient and TSS loads. 

  • Rules will be amended to require a volume management requirement.
  • Would depend on ability of developers to incorporate adequate BMPs on their projects and properly maintain them to sustain removal efficiencies.
  • Work cooperatively with LGUs to restore sport erosion problems.
  • Depends on extent of problem and ability to develop cooperative or collaborative improvements.
 
   

Stormwater velocity has caused erosion in the channel that conveys drainage from the southern subwatershed into the lake.

  • Staff will periodically inspect the channel for erosion
  • District will consider a cooperative project with LGU to stabilize channel

Depends on extent of problem and ability to develop cooperative or collaborative improvements.

Wetlands

The subwatershed includes four wetlands with high to exceptional vegetative diversity, fish and wildlife habitat and aesthetic values that should be protected.

  • Key Conservation Areas identified that include high-value wetlands.  In key areas, LGUs are required to include in their local plans strategies for conserving these values.
  • Ongoing effort that is dependant on property owner willingness to pursue conservation and LGU plan completion.
  • Rules will be amended to establish management standards based on management classification for impacts to wetlands from development and redevelopment.
  • Implementation of revised rules would help minimize future impacts to the highest-value wetlands while still providing a measure of protection to those that provide mainly downstream resource protection.
 
   

Wetlands with high to moderate restoration potential should be considered for protection and restoration.

  • Several potential wetland restorations are identified for potential collaborative restoration.
  • Wetlands identified as being of high to moderate wetland potential would be managed according to a Manage 1 wetland classification if they have been assessed as a Manage 2 or 3.   This would minimize further degradation that might make future restoration more difficult or costly.

Depends on extent of problem and ability to develop cooperative or collaborative improvements.  This would begin to mitigate wetland losses from past development and help to increase the quantity and quality of wetlands present.

Ecological Integrity

Few opportunities are available to conserve minimally disturbed landscapes, but there are potential restoration opportunities, including wetland restorations to improve and increase habitat; native vegetation restoration along the upper watershed channel; and urban forest restoration to increase evapotranspiration and reduce runoff.

 

Key Conservation Areas identified that include high-value wetlands.  In key areas, LGUs are required to include in their local plans strategies for conserving these values.

Ongoing effort that is dependant on property owner willingness to pursue conservation and LGU plan completion.

Wetlands with high ecological values are present and should be conserves and connected to provide wildlife corridors

Key Conservation Areas identified that include high-value wetlands.  In key areas, LGUs are required to include in their local plans strategies for conserving these values.

Ongoing effort that is dependant on property owner willingness to pursue conservation and LGU plan completion.

Christmas Lake is managed as a warm water-cool water lake and stocked with rainbow trout.  It may be sensitive to thermal impacts, or changes in groundwater flow.  Future development or redevelopment should take into acount potential thermal impacts to the lakes’s biota from direct runoff of stormwater, or from modifications to groundwater inputs.

 

Rules will be amended to add an abstraction requirement on new development and redevelopment to reduce new stormwater runoff and accompanying potential thermal impacts.

Would depend on ability of developers to incorporate adequate BMPs on their projects and properly maintain them to sustain abstraction volumes.

Detailed information is available on aquatic vegetation in Christmas Lake, but no management plan is in place.  Some Eurasian watermilfoil is present

Plan includes development of an aquatic vegetation management plan.

Completion of this plan would provide a plan for future activities by the District, LGUs, DNR, lake association, and other interested parties.

Groundwater

Groundwater input is likely an important component of the Christmas Lake water budget and changes in water quality over the past decades may be due in part to changes in that imput.  A more detailed model and analysis of Christmas Lake is necessary to better understand how both surface and groundwater inputs affect lake levels and water quality and to develop strategies for protecting this resource.

Plan includes such a study.

 

Depends on outcome of diagnostic study

The FAW concluded that the wetlands in the southern part of the subwatershed were discharge or combination discharge/recharge.  Increased infiltration in the southern subwatershed may be helpful in preserving that hydrology.

  • Amend rules to require infiltration or abstraction of the first one inch of rainfall on new permitted development and redevelopment.
  • Identify a network of surficial aquifer monitoring wells across the watershed, monitor groundwater levels and quality.
  • Promote Better Site Design (Low Impact Development) principles for new development that mimic predevelopment hydrologic regime.

 

Infiltration on site will assist in preventing further modification of surficial groundwater recharge and help to maintain wetland hydrologic regimes.

 

There are a number of areas in the subwatershed that are very highly or highly sensitive to aquifer impacts.

  • Amend rules to require pretreatment of stormwater discharged to wetlands or infiltration areas in the areas of high aquifer sensitivity.
  • Establish a new District rule that requires an additional level of analysis and review of permitted development and redevelopment where there is a potential for development to adversely impact groundwater connected to a surface water feature.

Will help minimize future impacts to groundwater and provide for proactive management rather than reactive

Stormwater management should be coordinated with wellhead protection plans.

 

Stormwater and groundwater management within those areas will be coordinated with wellhead protection plans.

Will help minimize future impacts to drinking water and provide for proactive management rather than reactive

 

Table 15.  Summary of metrics to be used in evaluating progress toward Christmas Lake subwatershed goals.

Objective

Metric

Existing

Desired

Location

Water Quality

Phosphorus Loading (lbs annually)

138 (Ultimate)

135

Christmas Lake

Water Quantity

Volume Reduction (Acre-feet)

-

0.3

Watershed-wide

1.5 year discharge (cfs)

708.8

708.8

Watershed-wide

100 year discharge (cfs)

708.8

708.8

Watershed-wide

Wetlands

Wetland Acreage

304.8

304.8 or greater

Watershed-wide

33.2

33.2 or greater

Preserve

9.4

9.4 or greater

Manage 1

5.4

5.4 or greater

Manage 2

10.0

10.0 or greater

Manage 3

Table 16.  Summary of Christmas Lake subwatershed implementation Program

Item

Description

Estimated Cost

Schedule

Section 3.0 Problems Addressed

MCWD Capital Projects

 

None identified

 

 

 

MCWD Data Acquisition/Study

1

Aquatic and shoreline vegetation survey and management plan

Part of watershed-wide hydrologic data program

Part of ongoing watershed-wide program

3.1.1, 3.1.2, 3.1.3, 3.1.5, 3.4.2, 3.4.3

2

Christmas Lake Long Term Water Quality Trends Study

$48,000

Not in 2007-2017 CIP

3.1.1, 3.1.2, 3.1.3, 3.1.4, 3.1.5, 3.2.1, 3.2.2, 3.2.3, 3.5.1, 3.5.3

3

Develop infiltration/filtration strategies appropriate to wellhead protection areas and areas of groundwater sensitivity

Part of watershed-wide study

2008

3.1.2, 3.2.3, 3.2.4, 3.3.1, 3.4.1, 3.4.2, 3..5.1, 3.5.2, 3.5.3

4

Identify keystone, umbrella, and indicator species, evaluate habitat, and develop conservation strategies

Part of watershed-wide study

2010 and ongoing

3.3.1, 3.3.2, 3.4.1, 3.4.2, 3.4.3

5

Inventory and prioritize erosion problems

Part of watershed-wide study

Part of ongoing watershed-wide program

3.3.1, 3.3.2, 3.4.1, 3.4.2, 3.4.3

MCWD Land Conservation Program

1

Undertake land conservation efforts in accordance with Figure 19

No District priority areas in subwatershed

Part of ongoing watershed-wide program

3.2.3, 3.3.1, 3.3.2, 3.4.1, 3.4.2, 3.5.3

MCWD Regulatory Program

1

Amend District Rules to require abstraction of 1” of rainfall from new development and redevelopment

Part of watershed-wide effort

2007-2009

3.1.1, 3.1.2, 3.1.3, 3.1.4, 3.2.1, 3.2.2, 3.2.3, 3.3.1, 3.5.1, 3.5.2, 3.5.3

2

Amend District Rules to adopt wetland management rules based on wetland management classification

Part of watershed-wide effort

2007-2009

3.3.1, 3.3.2, 3.4.1, 3.5.1, 3.5.2

MCWD Hydrodata Program

1

Monitor Christmas Lake

Part of watershed-wide hydrologic data program

Part of ongoing watershed-wide program

3.1.1, 3.1.2, 3.1.3, 3.2.2, 3.2.3

2

Identify shallow wells to monitor groundwater levels

Part of watershed-wide study

2008 and ongoing

3.2.2, 3.3.1, 3.3.2, 3.4.1, 3.5.1

MCWD Education/Communication Program

1

Provide targeted education materials to key stakeholder groups to meet objectives of plan

Part of watershed-wide education program

Part of ongoing watershed-wide program

3.1.1, 3.1.2, 3.1.3, 3.1.5, 3.2.2, 3.2.3, 3.3.1, 3.4.1, 3.4.2, 3.5.1, 3.5.2

2

Provide education opportunities for LGU staff, developers, elected and appointed officials and other interested parties

Part of ongoing watershed-wide education program

Part of ongoing watershed-wide program

3.1.1, 3.1.2, 3.1.3, 3.1.4, 3.1.5, 3.2.1, 3.2.2, 3.2.3, 3.3.1, 3.3.2, 3.4.1, 3.4.2, 3.4.3, 3.5.1, 3.5.2, 3.5.3

3

Develop and distribute model ordinances and design standards that incorporate low impact design principles

Part of watershed-wide education program

Part of ongoing watershed-wide program

3.1.1, 3.1.2, 3.1.3, 3.2.1, 3.2.2, 3.2.3, 3.3.1, 3.4.1, 3.4.2, 3.5.1, 3.5.2

4

Work cooperatively with the Christmas Lake Association

Part of watershed-wide education program

Part of ongoing watershed-wide program

3.1.1, 3.1.2, 3.1.3, 3.1.4, 3.1.5, 3.2.2, 3.2.3, 3.4.1, 3.4.2, 3.4.3

5

Recruit and train volunteers to monitor vegetation in Christmas Lake

Part of watershed-wide education program

Part of ongoing watershed-wide program

3.1.1, 3.1.2, 3.1.3, 3.1.5, 3.2.2, 3.4.2, 3.4.3

6

Develop a small grant program to provide financial assistance to property owners desiring to implement BMPs on their property

Part of watershed-wide program

2008 and ongoing

3.1.2, 3.1.3, 3.1.5, 3.2.1, 3.2.2, 3.2.3, 3.3.1, 3.4.1

MCWD Operations and Maintenance

1

Inspect erosion-prone reaches of the channel in upper watershed every year

Ongoing activity

Part of ongoing watershed-wide program

3.1.1, 3.1.2, 3.1.3, 3.1.4, 3.2.2, 3.2.3

Collaborative Projects

1

Streambank stabilization and restoration on the upper watershed channel to prevent erosion and sediment transport

Part of watershed-wide cost share program

2008 and ongoing

3.1.1, 3.1.2, 3.1.3, 3.1.4, 3.2.2, 3.2.3

2

Slope stabilization on the east side of the lakeshore

Part of watershed-wide cost share program

2008 and ongoing

3.1.1, 3.1.2, 3.1.5