Tuesday, October 9, 2007

Lake Whatcom: City's Stormwater Plan - Phocusing on Fosphorus

That title should read 'Focuses on Phosphorus', but maybe the misspelling will add a little humor to an otherwise pretty serious and sobering analysis.

Yesterday's blog promised more on this important subject, so here it is.

My review of the 58-page DRAFT Report recently produced by the consulting firm Parametrix, confirmed what I had suspected; the job we face in reducing the phosphorus level in our Reservoir will be difficult, costly and require many years to achieve.
But it can be done.
And, the sooner we get started, the shorter will be the time required, and the lower the overall costs.

That said, here is a synopsis.

The report is divided into 7 sections, subdivided as shown below:

1. INTRODUCTION

1.1 Structure of this Report

1.2 The Lake and its Watershed

1.3 Lake Phosphorus
1.3.1 Phosphorous and Lake Ecosystems
1.3.2 Lake Phosphorus Water Quality Criteria
1.3.3 Phosphorus in Lake Whatcom

1.4 Phosphorus Sources
1.4.1 Typical Sources and Pathways of Phosphorus to Lakes
1.4.2 Phosphorus Sources to Lake Whatcom
1.4.3 Future Source Identification

2. CURRENT CITY STORMWATER PHOSPHORUS CONTROL PROGRAM

2.1 Stormwater Retrofit Program
2.2 Mapping and BMP [Best Management Practice] Coverage
2.3 Monitoring and Maintenance Program
2.4 Ordinances
2.5 Acquisition/Easement/Transfrable Development Rights Programs
2.6 Enactment and Enforcement of Strict Development Restrictions
2.7 Yard Debris Collection Program
2.8 Street Sweeping Program
2.9 Incentives to Discourage Personal Motor Vehicle Use
2.10 Septic System Inspection and Certification Program
2.11 Planned Future Efforts

3. AVAILABLE PHOSPHORUS TREATMENT BMPS AND CITY BMP PERFORMANCE

3.1 Infiltration/Bioretention
3.2 Filtration
3.3 Wet/Dry Ponds
3.4 Swales
3.5 Wetlands
3.6 Review of City BMP Monitoring Data
3.7 Performance of City BMPS

4. PHOSPHORUS LOADING TO LAKE WHATCOM: PRELIMINARY APPROACH

4.1 Establishing Target Phosphorus Loading

4.2 Estimating Phosphorus Loading Rates by Land Use
4.2.1 Undeveloped Land Loading Rates (Smith Creek)
4.2.2 Developed Land Loading Rates (Silver Beach Creek)

4.3 Estimating Current and Future Phosphorus Loading Rates
4.3.1 Current Loading Estimate
4.3.2 Future Loading Estimate

4.4 Estimating Future Phosphorus Loading Rates Using Treatment BMPS
4.4.1 Future Development and Existing Development with South Campus BMP
4.4.2 Future Development with South Campus BMP, Existing Development with Current BMPS

4.4 Method Assumptions

5. OPPORTUNITIES AND RECOMMENDATIONS FOR ENHANCING THE CITY'S PHOSPHORUS STORMWATER MANAGEMENT PROGRAM

5.1 Enhancing Phosphorus Treatment BMPS
5.2 Applying BMPS to Single Lots
5.3 Updating and/or Adding Phosphorus Control Policies
5.4 Homeowner Policies
5.5 Waterfowl Control Options
5.6 Phosphorus Control Incentive Programs
5.7 Education Programs
5.8 Compliance Enforcement Programs
5.9 Stormwater Retrofit Program
5.10 Discontinue Deficit Financing of Infrastructure
5.11 Develop a Stormwater Index
5.12 Inventory/Mapping of TDR, Acquisition, and Easement Programs
5.13 Expanding the TDR, Acquisition, and Easement Programs to Include an Ecosystem Marketplace
5.14 Recommended Management Options

6. CONCLUDING REMARKS

7. REFERENCES
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As you can see this is not a superficial report!

It ranks phosphorus source areas in the following order of importance:

• Lawns/Landscaped Areas

• Residential Streets, Driveways & Sidewalks

• Stream Erosion

• Land Clearing & Other Disturbed Surfaces

• Animal Waste

• Stormwater Treatment Facilities

• Household Products

• Septic Systems

The main surprise in this listing is ' Stormwater Treatment Facilities.'
That means the ones in use aren't working very well to remove phosphorus - in fact some may be adding it!
That is not good news for people who believe that 'Stormwater Treatment Facilities' are the answer to everything.

If the current, worsening stuation weren't bad enough, existing zoning could allow an additional 3208 homes in this watershed which could add 16,000 more residents.
With that prospect, it would be prudent to establish, now, a target phosphorus loading that can be used to calculate what additional steps will need to be taken to achieve our watershed mangement goals.

Three options exist for establishing a target phosphorus loading rate to lake Whatcom:

1. No net increase.

2. Percent reduction over current loading estimate

3. TMDL

While we wait for the TMDL Report to get issued by DOE, time is wasting!
I believe setting an interim target loading rate ought to be done without further delay.
A value, not to exceed 20 micrograms per liter, would suffice and allow us to get on with monitoring phosphorus loading, at least by tributary.

That is one action the City -and County- need to take soon.

There are many other actions that are recommended, but they all help achieve that one.
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Without going into more detail here, the report itself is available for those interested.

But, the Report's concluding remarks make a good summary:

"The City has developed a comprehensive phosphorus control program that is achieving significant success in a difficult aspect of watershed management.
In order to maximize program effectiveness, the City should work with the County to develop a focused yet holistic approach to controlling phosphorus in stormwater runoff to Lake Whatcom from both existing and future development across the entire watershed.

It is recognized that although this report suggests opportunities specific to the City for improving its stormwater phosphorus control program (i.e., its portion of the Lake Whatcom watershed), phosphorus control efforts in other portions of the watershed are equally, if not more, important.
As noted, 98 percent of developable land in the watershed is located in the County.
Therefore, all recommendations, as well as all components of the City's current program, should be reviewed for opportunities to involve the County, DNR, and other entities and/or encourage them to incorporate similar management approaches when applicable.

Overall, findings of this review and evaluation are as follows:

• Phosphorus is difficult to control as evidenced by the City of Bellingham's experience as well as similar experiences documented by othe municipalities nationwide.

• Review of the literature and other stormwater programs indicates the City of Bellingham has, and is, employing the range of available technologies and BMPs for phosphorus control.

• Review of the literature also shows that the City of Bellingham could enhance its current program with additional emphasis on programmatic policies as well as improve existing treatment BMP performance.

• Future source identification and loading analysis may necessitate a re-evaluation and re-prioritization of the City's phosphorus stormwater management system."

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So there you have it.
We're doing a lot of stuff in our 2 % of the watershed, but it ain't working too well.

We need to do some more stuff, including changing human behaviors and convincing the County to do the same.

Once we get all that done, it will still likely take many years to stabilize the lake water quality.
But, it can be done.
And, it must be done, because we don't have another water source nearly as good as Lake Whatcom!
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