Haven’t heard of TMDL? You’re probably not alone and sadly many homeowners in Whatcom County may not learn about it until they open up their property tax assessments or try to sell their home. The acronym of TMDL, stands for “total maximum daily load.” This probably doesn’t mean much to you, but to keep it simple, the Department of Ecology (DoE) is proposing(?), or mandating(?) due to the Clean Water Act from the EPA (environmental protection agency) that surface water run-off from impervious surfaces be reduced by 87%.
Currently surface water run-off is handled in many ways on our homes and property. Gutters, down-spouts, drain tiles, french-drains, ditches, culverts and retention ponds are many of the common processes currently in use. One thing that all of these processes have in common is that eventually the water enters the city sewer system or the surrounding water sources. The goal of DoE’s surface water reduction, or benchmark, for TMDL is to prevent that run-off from entering the storm water system or natural waterways, thus reducing the elevation of phosphorous introduction into Lake Whatcom. It has been determined that phosphorous loading to the lake is an issue for Lake Whatcom water Basins 1 and 2. This problem does not occur in Lake Whatcom’s Basin 3, because this basin is much larger, deeper and colder than Basins 1 and 2. Thus Basin 3 has better water temperature stratification and a larger area of cooler water. Cooler water is not conducive to algal bloom, which is the sole solution that the DoE is recommending to reduce phosphorus loading from the surface water run-off. Phosphorus loading when combined with warmer water does increase algal bloom, which contributes to hypolimnetic oxygen depletion rate (HODR) , according to many studies with the results in a lack of dissolved oxygen to properly sustain marine life and a healthy water ecosystem.
Councilman Sam Crawford asked a very pertinent question at the March 26th, Natural Resources (NR) committee meeting,; “Can we approach the algae effect differently? Could we do a relatively inexpensive (?) retrofitting of a water pump and get the cooler water? Would this be a better option? If we were to pump water from Basin 3 to Basins 1 and 2, to cool the water temperature of these basins, would we have less algae growth, thus less concern for phosphorus? If phosphorus is only an issue for algae growth, why do we care? Would this facilitate the public better and cost much less overall?” (Planning Commissioner David Onkels agrees with this premise, but thinks that the inverse should be applied; pumping water from Basins 1 and 2, into Basin 3. The differences between the two actions being that Onkels plan would still circulate and cool Basins 1 and 2, and limit the re-deposition of phosphorus into the water column.)
Steve Hood, of the State of Washington’s Department of Ecology replied; “We’d want to model it first. We don’t know if this would help the problem with the blue-green algae, which is not good for fish. Theoretically keeping the lake cooler could work. Stirring the lake could release some phosphorus from the lake bottom, but possibly.”
For the past ten years (or more) the Department of Ecology have been studying and monitoring Lake Whatcom. At this NR meeting it became abundantly clear to me that the DoE’s program and thus their presentation was narrowly focused on cause and solution. With no regard to the property rights or pocketbooks of the people who will be impacted by this program, the Doe is proposing that between the years 2015 – 2020, the County consider two potential plans. One plan would focus on; “What’s the cost in 50 years? Do the homeowners pay for these improvements?” The second plan will look at; “How can the homeowners be incentivized to make the needed changes to achieve the phosphorous reductions that are needed?” Along with this line of thinking they would lay-out these benchmarks; study focus, loading models, lake models, integrations and assessments. The DoE’s data has been gathered over the past ten years starting in 2002 using these two programs:
Their study covered water temperature and phosphorus loading on a per acre contribution from developed areas v. forested land. The outcome of the study showed that yes there is more phosphorus on developed land v. forested land and gave this one recommendation on how best to reduce phosphorus loading. But, is the problem the amount of phosphorus? Or, is the real problem what it creates, increased algal bloom? Algal bloom decreases the dissolved oxygen levels in the water. Algal bloom feeds off phosphorous and is enhanced by low water volume, temperature increases and low water circulation, or stagnant water. Seems to me that all of our elected officials should be asking this question; “Can we fix the problem without having to bankrupt our communities, destroy millions if not billions of dollars of high valued real estate and forever limit the communities ability to grow and diversify?”
~ Kris Halterman
And yet another more science specific, perspective is given here by Planning Commissioner David Onkels; “Facts from the field Lake Whatcom Watershed Overlay.doc”