River Flow Gauge on Youghiogheny River Above Deep Creek Nexus

River Flow Gauge on Youghiogheny River Above Deep Creek Nexus

Our next objective is to accrue donor funding of $21,750 in capital costs and a commitment of $17,970 for annual operation and maintenance for the gauge on the river upstream of where Deep Creek joins the Youghiogheny. The existing flows at that point subtracted from the flows measured at the Hoyes Run gauge will indicate the discharges from the Deep Creek watershed, including flows from the power plant and groundwater discharges.

The Completed Water Budget Model will be able to account for precipitation, groundwater recharge, flows through the power plant plus the discharges around the dam, factoring in the discharges required through the power plant by the Water Appropriation Permit. An apparently simple relationship determines the water levels in the lake: Water In – Water Out = Change In Water Level.

A recent bathymetric survey of Deep Creek Lake confirmed the Stage-Storage relationship determined when the lake was built by Youghiogheny Hydro-Electric Company. The project partially fulfills Goal 1 of the Watershed Management Plan.

The new USGS flow gauge upstream of the Swallow Falls Bridge on the Youghiogheny River will measure the river flows upstream of the power plant. The difference in flows, adjusted for travel time, will afford an indication of the discharges from the Deep Creek Watershed.

The discharge from the watershed (Water Out) is a component in the analysis of the groundwater recharge and the precipitation (Water In). The other component is a record of lake water levels.The public doing recreational boating and swimming in the river reach from Swallow Falls to the Sang Run Bridge will be safer because the river flow rate is conveniently available on the USGS

Water Level Dock Impacts

Water Level Dock Impacts

Part of the Water Budget Model design work includes an evaluation of impacted docks at the water levels contained between the Rule Bands.  According to the report, there are 2,233 docks on the lake.  At the end of August, the Lower Rule Band (LRB) is at 2458, and 202 docks, 9% of the total, are impacted by low water.  At the end of September, the LRB is at 2457, and 267 docks, 12% of the total, are impacted.  At the end of October, the LRB is at 2456, and 335 docks, 15% of the total, are impacted by low water.

The dock impacts from lowered water levels study was done by Century Engineering in Oakland, Maryland and cost about $30,000. This project partially fulfills Goal 10 of the Watershed Management Plan.

Predicting New Lake Water Levels

Predicting New Lake Water Levels

We paid about $70,000 to an engineering firm to develop a new method for predicting the water level of Deep Creek Lake.  Called the Water Budget Model (WBM), it will allow the Brookfield Renewable Power Company, which operates the dam on Deep Creek Lake, to time water releases from the dam in light of the anticipated water height in the lake.

The WBM created by the foundation is currently limited to predictions based on the water remaining in the pool above the lower rule band and the mandated releases from the dam. The forecast is limited to about thirty days. The current model is particularly useful during summer when the demand for water into and out of Deep Creek Lake. This project partially fulfills Goal 12 of the Watershed Management Plan.

Zebra Mussel Monitoring

Zebra Mussel Monitoring

We have joined with Brookfield Renewable Power, to help the Maryland Department of Natural Resources test the waters and habitats in Deep Creek Lake to see if there are any indications that the lake has been invaded by the terribly destructive Zebra Mussels, a species originally native to the lakes of southern Russia and Ukraine.  These mussels, which have invaded other lakes in the U.S., including rivers and lakes near us, are usually carried into lakes on the bottom of boats.  They have sharp shells that are a danger to swimmers who step on them, they clog hydroelectric dams, and they have a toxin that has killed thousands of birds.  The tests so far have yielded the good news that Deep Creek Lake shows no presence of Zebra Mussels, and we are keeping up the watch for these and other dangerous invaders.

Water Drawdown Efficacy and Implications

Water Drawdown Efficacy and Implications

Executive Summary 

Macrophytes or Submerged Aquatic Vegetation (SAV) are often part of many aquatic systems. Carried by wind or waterfowl or (un)intentionally introduced by humans, SAV can quickly establish. Understanding the role that these plants play in the ecology of a system is an important step to developing methods to control their unwanted spread. Here, an overview is provided of the current SAV status of Deep Creek Lake, Maryland as well as an evaluation (literature review) of the potential effects of various control strategies (e.g., winter drawdowns) within the ecosystem, both biotic and abiotic. 


Lakes and reservoirs are frequently developed into recreational havens for boaters and fisherman alike. In addition, many serve concurrently in more industrial or ecological roles as hydroelectric power sources or as flood control/management devices. Conditions among many of these lentic systems often lend themselves to invasions of aquatic nuisance species like Zebra Mussels (Dreissena polymorpha) and Hydrilla (Hydrilla verticillata). Recreational boaters for example can easily introduce and spread such invaders unintentionally with movement of their vessels from waterbody to waterbody. In some instances, systems become overrun by these nuisance species which necessitates drastic measures be employed. Macrophytes or submerged aquatic vegetation (SAV), if left unchecked, can create severe problems, turning once productive systems into eutrophic nightmares. 

Submerged aquatic vegetation is defined as plants that are usually rooted in the bottom soil with the vegetative parts predominantly submerged. While rooted vegetation can provide shelter, habitat, and food for many organisms as well as oxygen through the process of photosynthesis, some plants pose threats to aquatic systems choking out native species. This review serves as an assessment of the effects of winter drawdowns, both positive and negative across various taxa. Other control methods are 

discussed, but the focus will be water withdrawal (mechanical control). It is intended to provide guidance for the Deep Creek Watershed Foundation as they tackle increases in SAV around the Lake. 

Current Status of SAV in Deep Creek 

Vegetation surveys were performed by MD Department of Natural Resources (DNR) between 2018 and 2020 to track SAV movement and expansion in Deep Creek Lake (Table 1). Three species appear to dominate: a species complex of Water Milfoil (Myriophyllum spp.), Broad-leafed Pondweed (Potamogeton amplifoilus), and Wild Celery or Tape Grass (Vallisneria americana). For the purposes of discussion, these three macrophytes will be the focus to assess the varying ecological effects of SAV. 

Table 1 – Summary of vegetation present in Deep Creek*. Data collected by and obtained from the MD Department of Natural Resources. I = introduced and N = native. 

Water Drawdown and Efficacy Table 1

A. Water Milfoil Complex and Eurasian Watermilfoil 

There are native species of milfoil that may benefit fish by providing cover and by serving as a source of food for various wildlife species; however, its prolific growth often limits these values. In fact, excessive growth can reduce oxygen supplies that result in fish kills. Perhaps the most concerning species of milfoil is the Eurasian Watermilfoil (Myriophyllum spicatum, EWM), a native to Europe, Asia and North Africa (Nichols and Shaw 1986; Eiswerth et al. 2000; Fig. 1), and one that, while identified by the MD DNR, is likely a component of the mifloil complex (Table 1). 

Figure 1 – Image showing native Low Watermilfoil (left) and introduced Eurasian Watermilfoil (right). While the exact dates of its introduction in the United States are unknown, it likely occurred

sometime after the 1880s. It is often confused with the native Northern Milfoil (Myriophyllum exalbescens) and although its density in Deep Creek Lake appears low for now, it has the ability to rapidly spread.

Ecologically, EWM presents some issues due to its prolific reproduction (it can reproduce both sexually and asexually) and ability to crowd out native species (Smith and Barko 1990). In addition, EWM spreads when brittle plant pieces break off, float on the water currents, and re-root elsewhere (Aiken et al. 1979; Madsen et al. 1988). It may also hitchhike on boats and fishing gear, increasing its

movement within a lake or between neighboring bodies of water (Johnstone et al. 1985). It is typically most abundant in water between 1 and 4 m deep (Nichols and Shaw 1986) but can be found at depths of up to 7 m (Reznicek et al. 2011) or as deep as 10 m (Aiken et al. 1979). When it reaches the water’s surface it can form a dense canopy mat (Aiken et al. 1979).

Invertebrate and fish communities in EWM differ from those associated with other SAV. Dvorak and Best (1982) found that EWM had the poorest macroinvertebrate fauna and 3 to 4 times fewer fish than pondweed-wild celery communities. The characteristics described above make the milfoil complex a group to watch vigilantly, curbing its spread to reduce its chances of forming dense aggregations.

B. Broad-leafed Pondweed

A North American native, Broad-leafed Pondweed (BLP; Potamogeton amplifolius) has increased in size within Deep Creek, becoming a species dominant (Table 1; Fig. 2). Pondweeds can provide excellent fish cover (Craig 1952). BLP is often found at depths between 1 and 4 m (Wakeman and Les 1994) in calm water which is preferred by Bluegill (Lepomis macrochirus) for nesting and feeding (Tomcko and Pereira 2006).

Broad Leaf Pond Weed

However, if left unchecked BLP can grow pervasively, dispersing quickly within an aquatic system. Options available to curb its spread include biological, chemical, or mechanical removal (Texas A&M 2022b). Biological removal would require introducing Grass Carp (Ctenopharyngodon idella); but this would not be an option in Maryland as the Department of Natural Resources has banned this fish from all waterways (MICRA 2015). Chemical removal using various herbicides (Texas A&M 2022b) has also been proposed as a removal method but may be viewed negatively by the public. Mechanical removal by raking or dredging the waterbody is an option likely not available to Deep Creek Lake due to the recreational activities that are a focus of this waterbody. However, winter drawdowns (more on this below), another mechanical control, may be a more viable option, especially in large lake or reservoir systems. This will be discussed further below.

C. Wild Celery

Wild Celery (WC, Vallisneria americana) is a fast-growing perennial aquatic macrophyte (Fig. 3). With ribbon like leaves it is often found rooted in mud, growing among pondweeds. In lakes it can grow to a few meters in length and, if the substrate is suitable, form large mats of grass in late summer (Korschgen and Green 1988). It provides shelter for juvenile fish like Perch (Perca flavescens) and provides cover for Bass (Micropterus sp.) and Bluegill. It is also an excellent food choice for waterfowl, particularly diving ducks, like Canvasbacks (Aythya valisineria) and Scaups (Aythya sp.) (Korschgen and Green 1988).

This plant is best left alone because of the benefits it offers to fish and wildlife species; however, if left unchecked it may interfere with recreational activities like boating and fishing. Large aggregations can foul outboard motors and the thin ribbon-like leaves can become attached to fishing lures. Herbicides do not work well to control this plant and mechanical removal often fails because uprooted plants can re-establish themselves (MN DNR 2022; Texas A&M 2022a).

Summary of SAV in Deep Creek and proposed management strategy 

The aforementioned section describes the general nature of three-dominant plants (complexes) present in Deep Creek Lake, each with their own benefits and dispersal strategies. While some are viewed as nuisance species others are viewed as very beneficial to fish and wildlife alike. Management of SAV is paramount to the continuing success of Deep Creek Lake. WDFW (2015) recommends developing a vegetation management plan to control and remove aquatic plants. A vegetation management plan is a comprehensive approach to controlling aquatic plants where all strategies are first considered and usually some combination of techniques is selected and implemented. These plans should be based on the biology and ecology of the aquatic plant(s) to be controlled and the environmental characteristics of the site. As a result, data (e.g., Table 1) about the system should first be assembled and analyzed. 

Of the three basic control methods (mechanical, biological, and chemical), mechanical control can be the least expensive and most convenient. Moreover, public support is often greater for this method because chemicals are not being introduced into the environment (University of Florida 2021), 

or a non-native species like Grass Carp. Deep Creek Watershed Foundation is proposing to employ a seasonal drawdown strategy to control the spread of several aquatic macrophytes. 

Unlike raking or physical removal, winter drawdown exposes plants to air-drying and freezing temperatures. The desiccation process can accelerate erosional processes which reduce fine-textured sediment (Effler and Matthews 2004; Cooley and Franzin 2008), organic matter, and nutrients (James et al. 2001; Furey et al. 2004). This in turn can leave behind larger sediment particles with low nutrient storage capacity. These abiotic changes along with direct physiological stresses from desiccation and freezing conditions can reduce macrophyte abundance and alter assemblage composition (Wilcox and Meeker 1991; Wagner and Falter 2002; Turner et al. 2005; Carmignani and Roy 2017). 

The practice of water level manipulation reduces water levels to some predetermined quantity and is generally designed to expose portions of a lake bottom inundated with nuisance plants. Manipulating water levels (drawdowns) to remove or control aquatic noxious weeds and/or exposing plants and root systems to extreme temperature and moisture conditions may be appropriate under certain circumstances (WDFW 2015). Winter drawdowns and subsequent spring refills (Fig. 4) are a common lake and reservoir management practice to achieve a variety of human goals. 

Drawdowns occur as early as November/December and can continue through April (NYSDEC 2005, Carmignani and Roy 2017; Fig. 4). However, this timetable can vary depending on the management objective and the seasonal climate (WDFW 2015). Historically, fishery managers used winter drawdowns to concentrate prey populations, this in turn stimulated piscivorous sport fishes by reducing prey refuge habitat (Hulsey 1957; Lantz et al. 1967; Groen and Schroeder 1978). This action promoted macrophyte growth which served as important spawning and rearing areas for these species (Fox et al. 1977). Fisheries managers also used drawdowns to attempt to eradicate undesired fishes 

Relative Water Level

(Verrill and Berry Jr. 1995). Today, drawdowns have expanded value because many reservoirs have been developed for hydroelectric power generation. Winter drawdowns can help to meet the increased energy demand in such reservoirs during winter months (Aroviita and Hämäläinen 2008) and provide storage in anticipation of seasonal spring flooding (Hellsten 1997).

In recreational lakes, annual winter drawdowns can serve as a preventative measure to protect docks and retaining walls from ice scour damage, permit shoreline cleanup, and reduce nuisance levels of aquatic vegetation (Cooke et al. 2005). This can be an effective control technique, especially if done in successive years (NYSDEC 2005; Carmignani and Roy 2017). Water level manipulation can also provide a good opportunity to perform minor dam repairs and improve or enhance shorelines. Here, a literature review is provided that explores the ecosystem implications (both biotic and abiotic) of winter drawdowns.


A. Plants/Habitat

Studies have documented reduced macrophyte biomass and density from drawdown exposure compared to reference systems or previous non-drawdown conditions (Tarver 1980; Wagner and Falter 2002; Turner et al. 2005; Beklioglu et al. 2006; Sutela et al. 2013). Drawdowns of relatively large amplitude (e.g., >2-3 m) can significantly reduce macrophytes (Rorslett 1989; Turner et al. 2005; Keto et al. 2006; Sutela et al. 2013), while relatively mild drawdowns (<1.5 m) show less impact on density (Keto et al. 2006), potentially increasing macrophyte richness (Mjelde et al. 2012).

Response to drawdowns can be species specific and in some cases nuisance species are stimulated to grow (Cooke 1980). Turner et al. (2005) monitored the aquatic plant community in an experimental lake drawdown. They documented an initial two-thirds reduction in littoral macrophytes, however, recovery was variable among species. Of the species monitored, cool season grasses (Carex spp.) were nearly absent, milfoil (Myriophyllum spp.) were relatively unaffected, and pondweed (Potamogeton spp.) increased in biomass and frequency. McGowan et al. (2005) and Hudon (2004) noted similar increases in pondweeds following reductions in lake level.

The frequency of drawdowns may also play a role in determining the species composition of macrophytes. Ruderal (stress-tolerant) or semi-ruderal species may prevail. Ruderal species are characterized as fast growing with early reproduction and high annual seed production (Grime 1977; Rørslett 1989). They tend to have multiple reproduction strategies to increase the likelihood of individual persistence and population growth (Tazik et al. 1982; Siver et al. 1986). Rising water temperatures and concomitant ice-off in the spring promote rapid establishment of ruderal species, limiting growth of other macrophytes (Wagner and Falter 2002).

The viability of seed banks can last for multiple years until suitable germination conditions arise (Howard and Wells 2009). Generally, sediment desiccation stimulates seed germination (Keddy and Reznicek 1986) and facilitates propagation in the drawdown exposure area (McGowan et al. 2005). Species that produce seeds (e.g., Najas minor, Potamogeton pectinatus) are expected to dominate assemblages with increasing lakebed desiccation intensity and frequency (Bornette and Puijalon 2011; Arthaud et al. 2012). Further, the likelihood of persistence for drawdown-tolerant taxa increases because of reduced competition (i.e., for nutrients, light, and space) with more sensitive species (Hellsten 2000; Boschilia et al. 2012).

While drawdowns may favor ruderals, other macrophyte species are restricted to low densities or are extirpated. Taxa most vulnerable in the drawdown exposure zone include perennial species (e.g., many Potamogeton spp.) that rely heavily on rhizomic structures for propagation (Siver et al. 1986), obligate-submergent species (Thomaz et al. 2006; Boschilia et al. 2012), and species sensitive to ice scour (Hellsten 2002).

The response among macrophytes therefore, largely depends on species’ tolerance to freezing, its life-history strategy, and its geographic proximity. Studies summarized from New York (NYSDEC 2005) and Cooke (1980) seem to offer dissimilar results with same plants either positively or negatively affected by drawdown (Tables 2 and 3; e.g., pondweed). Carmignani and Roy (2017), note that assemblage composition is a function of the hydrological components of the drawdown regime (e.g., frequency, duration, and amplitude), competitive interactions, and the species-level tolerance to drawdown-related disturbance (e.g., desiccation, low temperatures, erosional forces) – all factors that likely influence the results documented.

Table 2 – Summary of common macrophytes in New York and their response to winter drawdown.

Table 2 – Summary of common macrophytes in New York and their response to winter drawdown.

Table 3 – Summary of common macrophytes summarized by Cooke (1980) and their response to winter drawdown.

Table 3 – Summary of common macrophytes summarized by Cooke (1980) and their response to winter drawdown.

B. Fish

By reducing the water level, forage fish such as Bluegill, are driven out of shallow water refuges and concentrated in open water, making them more vulnerable to Bass predation. This is a good technique to use in waterbodies that may be overrun with Bluegill because the increased predation by Bass reduces Bluegill numbers and provides additional food for Bass and other predatory fishes. In some cases, routine annual drawdowns have helped managers maintain a balanced Bass/Bluegill fishery. In addition to predatory fish, birds may also benefit by preying on concentrations of fish and invertebrates.

Fredrickson (1991) recommended a slow drawdown to give aquatic organisms an opportunity to disperse from the aquatic plant cover. Brush tops and gravel beds, which serve as fish attractors, can be easily placed while the water is down – thereby providing cover once the lake refills. While studies such as these demonstrate positive effects, removal effects of SAV on fish are somewhat inconsistent, likely because of experimental circumstances and location. For example, Colle and Shireman (1980) report that Bluegill condition and relative abundance declined following water level manipulation (Bettoli et al. 1993). But other research by Cross et al. (1992), Radomski et al. (1995), and Slade (2005) document that Bluegill remain unchanged when vegetation was removed. And still other studies report improvements of survival and population structure (Unmuth et al. 1999). One study performed over a 3-year period demonstrated the resilient nature of fish communities to recover and the ability of aquatic plants to re- sprout after the water body refilled (Paller 2011). So, the effects of water withdrawal on fishes are not definitive.

Shifting plant communities may reduce overhead cover (Bodaly and Lesack 1984) or eliminate spawning grounds previously available to fishes. Water level fluctuations can also alter fish behavior, distribution, and growth. Movement of Largemouth Bass (M. salmoides) and Northern Pike (Esox

lucius), noted by Rogers and Bergersen (1995), occurred in reservoirs between normal and drawdown conditions. Perhaps even more critical to fish is the availability of dissolved oxygen.

Cott et al. (2008), investigated the effects of winter water withdrawal on oxygen concentrations in small (<30 ha) lakes. They demonstrated that oxygen depletion brought on by drawdowns can be compounded by environmental factors like snowfall. Large volumes of water (10 and 20% of their respective under-ice volumes) were withdrawn from two lakes and compared with reference conditions. Under both scenarios, oxygen concentrations were depressed and further reduced with heavier snowpack.

Winter drawdown of reservoirs can induce winterkill if oxygenated water is removed through drawing or flushing the oxygenated surface waters within a reservoir, leaving only poorly oxygenated water (Gaboury and Patalas 1984; Järvalt and Pihu 2002). Drawdowns can also affect fish and other components of the aquatic ecosystem through partial or complete reduction of littoral habitat (refer to habitat section).

C. Macroinvertebrates

Several studies reported significant effects of water level fluctuations on macroinvertebrate abundances and community composition (Furey et al. 2006; Aroviita and Hämäläinen 2008; White et al. 2008, 2011; McEwen and Butler 2010). The amplitude in water level fluctuations or the area exposed by drawdown was a key component to the response among macroinvertebrates who exhibited shorter life cycles and higher mobility in reservoirs with extensive winter drawdowns (Aroviita and Hämäläinen 2008; McEwen and Butler 2010; White et al. 2011).

With respect to taxa richness, research does not provide a decisive result. Aroviita and Hämäläinen (2008) and White et al. (2010, 2011), reported declines in taxa richness among macroinvertebrates sampled at relatively shallow depths (<5 m) but Furey et al. (2006), who sampled areas from 3.5 to 12.5 m reported an overall higher number of taxa in the reservoir, especially below the drawdown zone. These results, much like those reported for fish could, in part, be explained by differences in sampling approaches among studies.

Wetzel (2001) suggests that patchiness in the abundance and distribution of macroinvertebrates within lentic systems can be attributed to species’ physiological limitations, competition, predation, resource availability, and other factors. For example, Rasmussen (1988) showed that littoral zoobenthic biomass was strongly related to submerged macrophyte biomass and localized slope. Both factors can influence the amount of available food as the former provides periphyton and allows for the deposition of organic-rich detritus whereas steep slopes prevent macrophytes from establishing. Because aquatic insects often require emergent vegetation to complete their metamorphosis from larva to adult (Thorp and Covich 1991), winter drawdowns designed to reduce vegetation would directly impact their life cycles.

Winter drawdown can expose bottom substrates to temperatures below 0oC, or lead to ground- fast ice, consequently freezing the associated invertebrate community. This freezing may cause shifts in benthic invertebrate community structure because of species-specific tolerance levels to freezing and temperature regimes. Furey et al. (2006) noted that biomass and densities were greater in a regulated reservoir and that the effects of drawdown on benthic macroinvertebrates extended below the drawdown exposure area. In a similar study, Trottier et al. (2019) report that some species were resistant to desiccation (e.g., Chironomids, Oligochaetes and Sphaeriids), flourishing in the littoral areas of the regulated systems. They caution that such changes could have implications for food web structure and ecosystem function.

D. Other Semi-Aquatic Organisms

Semi-aquatic organisms that are seasonally dependent on aquatic systems for food or refuge (e.g., frogs, turtles, beavers, muskrats, waterbirds) are likely to experience some type of stress or reduction during a portion of their life cycle in association with drawdowns. With respect to birds, aquatic macrophytes offer suitable nest substrate, protective cover, food availability, and territorial requirements (Johnsgard 1956). The physical structure of the vegetation and its successional stage, rather than its taxonomic composition, is of greatest importance to nesting birds (Weller 1978). Hemi- marsh, a 1:1 ratio of emergent vegetation and open water (Weller and Spatcher 1965; Nelson and Bowyer 2000) is commonly recognized as ideal for many bird species throughout later portions of their seasonal cycle. Aquatic vegetation (as foliage, shoots, tubers, and seeds) constitutes a portion of the diet of many birds (Weller 1981). However, invertebrates may represent a greater part of the diet, especially during the breeding period. For example, Murkin et al. (1982) concluded that although blue-winged teal (Anas discors L.) and mallards (Anas platyrhynchos L.) preferred hemi-marsh habitat, their densities were dependent on invertebrate abundance. Similar responses are seen among furbearing mammals.

Muskrats for instance make denning houses in shallow water bodies using mud and aquatic vegetation. Dannel (1978) found that many muskrat lodges were within 1 m of water depth, and the mean water depth at lodge sites was 0.2 m. Relatively constant water levels are required to enable muskrats to access food and construction materials during periods of ice-cover (Glass 1952). Winter water level reductions can prevent semi-aquatic animals such as muskrats from accessing their burrows (Avakyan and Podol’skii 2002).

Water level fluctuation and control is the primary method of muskrat population management as it is the most influential variable determining muskrat abundance, even more so than the type of vegetation present. In winter, muskrats feed on plant material under the ice (Allen and Hoffman 1984); changes to water level regimes that influence the amount of plant material in feeding areas and low water may lead to freezing of food resources that would otherwise be available. Further, when muskrats are forced to search for food during winter, they run an increased risk of being frozen out of their dens (Perry 1982).

If water levels are too low, muskrats are forced to find new feeding areas, increasing their vulnerability to predation and hypothermia. Drought or other low water events can concentrate muskrats, leading to higher rates of social conflict, predation, and disease (Perry 1982). Reduced water levels can prevent the establishment of plants such as cattails (Typha sp.) that muskrats use for food and building materials. Parasite loading and disease also increase with suboptimal water levels (Perry 1982). So, even though a semi-aquatic organism, muskrats could be detrimentally impacted by water withdrawal.

E. Abiotic (Chemical) conditions

Water withdrawals can affect many different aspects of the physical and chemical nature of a waterbody. Water-level manipulation can favor the oxidation and mineralization of organic phosphates (P) (De Groot and Van Wijck 1993). This however largely depends on the precise changes in sediment chemistry, structure, and organic matter sources (e.g., macrophytes, Watts 2000) and the release of sedimentary P on reflooding. For example, Twinch (1987) reported greater releases of P upon- reflooding were a result of changes in sediment composition. Moreover, Klotz and Linn (2001) indicated that P release because of drying was correlated with sediment P and organic content suggesting that drawdowns may increase P loading in lakes rather than decreasing it.

Similarly, sediment desiccation can alter nitrogen (N) cycling by increasing aerobic nitrification and nitrate buildup in sediments (Kadlec 1962) or by mineralizing sedimentary organic-N and intensifying denitrification in underlying anoxic sediments (De Groot and Van Wijck 1993). McGowan et al. (2005) showed that drawdowns of 50% resulted in elevated NH4-N (Ammonia-Nitrate) concentrations but other parameters monitored changed little. Wichelen et al. (2007) report that that drawdown resulted in sediments with a lower water and organic matter content and water column turbidity decreased after the drawdown. But pH in the southern basin of their study declined to <4, probably because sulphides in the sediment were oxidized during drawdown and sediment desiccation (Wichelen et al. 2007). Like biotic variables, the results are varied documenting changes in abiotic factors. Therefore, a good understanding of the chemistry and surrounding geology will be an important consideration before a winter drawdown is considered.


Winter drawdowns can offer many benefits including: reducing SAV and nuisance or overcrowded fish populations, changing the composition of plant and animal species, and providing electrical power in winter and water storage in spring. However, the timing and duration of drawdowns can negatively impact species by compressing life histories and changing food web structure.

Regarding Deep Creek Lake, data should continue to be collected concerning the spread and or invasion of various plant species like those listed in Table 1. Identification of all aquatic plants will be an important part of this process as this may determine the efficacy and longevity of drawdowns. In addition, available fish data should be evaluated to determine the species composition and if possible, the size structure of various populations; moreover, other data from the lake should be incorporated as available (e.g., bird or macroinvertebrate surveys and chemical information). A timeline similar to that proposed by WDFW (2015; e.g., Table 2) should be developed to achieve the desired goals of the Deep Creek Watershed Foundation.

The proposed dredging of Arrowhead Run Cove may prove instructive to assess the physical changes associated with drawdowns and the mechanical removal of both plants and silt. This could serve as a model of sorts to determine what other data should be assessed to determine the efficacy of such an action at Deep Creek Lake and what the implications may be.

Literature Cited

Aiken, S. G., P. R. Newroth, and I. Wile. 1979. The biology of Canadian weeds. Myriophyllum spicatum L. Canadian Journal of Plant Science 59: 201-215.

Allen, A.W. and R.D. Hoffman. 1984. Habitat Suitability Index Models: Muskrat. U.S. Fish and Wildlife Service, FWS ⁄ OBS82 ⁄ 10.46. 27 pp.

Aroviita, J. and H. Hämäläinen. 2008. The impact of water-level regulation on littoral macroinvertebrate assemblages in boreal lakes. Hydrobiologia 613:45-56.

Arthaud, F., D. Vallod, J. Robin, and G. Bornette. 2012. Eutrophication and drought disturbance shape functional diversity and life history traits of aquatic plants in shallow lakes. Aquatic Science 74:471- 481.

Avakyan, A.B. and S.A. Podol’skii. 2002. Impact of Reservoirs on the Fauna. Water Resources 29(2):123-132.

Beklioglu, M., G. Altinayar, and C.O. Tan. 2006. Water level control over submerged macrophyte development in five shallow lakes of Mediterranean Turkey. Archiv für Hydrobiologie 166:535-556.

Bettoli, P.W., M.J. Maceina, R.L. Noble, and R.K. Betsill. 1993. Response of a reservoir fish community to aquatic vegetation removal. North American Journal of Fisheries Management 13:110-124.

Bodaly, R.A. and L.F.W. Lesack. 1984. Response of a Boreal Northern Pike (Esox lucius) Population to Lake Impoundment: Wupaw Bay, Southern Indian Lake, Manitoba. Canadian Technical Report of Fisheries and Aquatic Sciences 41:706-714.

Bornette G. and S. Puijalon. 2011. Response of aquatic plants to abiotic factors: a review. Aquatic Science 73:1-14.

Boschilia S.M., E.F. De Oliveira, and A. Schwarzbold. 2012. The immediate and long-term effects of water drawdown on macrophyte assemblages in a large subtropical reservoir. Freshwater Biology 57:2641-2651.

Carmignani, J.R. and A.H. Roy. 2017. Ecological impacts of winter water level drawdowns on lake littoral zones: a review. Aquatic Sciences 79:803-824.

Colle, D.E. and J.V. Shireman. 1980. Coefficients of condition for largemouth bass, bluegill, and redear sunfish in Hydrilla-infested lakes. Transactions of the American Fisheries Society 109:521-531.

Cooke, G.D. 1980. Lake level drawdown as a macrophyte control technique. Journal of the American Water Resources Association 16:317-322.

Cooke, G.D., E.B Welch, S.A Peterson, and S.A. Nichols. 2005. Restoration and management of lakes and reservoirs, 3rd ed. CRC Press Boca Raton, Florida.

Cott, P.A., P.K. Sibley, A.M. Gordon, R.A. Bodaly, K.H. Mills, W.M. Somers, and G.A. Fillatre. 2008. The Effects of Water Withdrawal from Ice-Covered Lakes on Oxygen, Temperature and Fish. Journal of the American Water Resources Association 41:328-342.

Cross, T.K., M.C. McInerny, and R.A. Davis. 1992. Macrophyte removal to enhance bluegill, largemouth bass, and northern pike populations. Minnesota Department of Natural Resources, Section of Fisheries Investigational Report 415, St. Paul, Minnesota.

Dannel, K. 1978. Intra- and Interannual Changes in Habitat Selection by the Muskrat. Journal of Wildlife Management 42(3):540- 549.

Cooley, P.M. and W.G. Franzin. 2008. Predicting the spatial mud energy and mud deposition boundary depth in a small boreal reservoir before and after draw down. Lake and Reservoir Management 24: 261-272.

Craig, V.E. 1952. A story of fish production as it applies to Montana. M.S. Thesis. Montana State University, Bozeman, Montana.

Dvorak, J. and E.P. Best. 1982. Macro-invertebrate communities associated with the macrophytes of Lake Vechten: structural and functional relationships. Hydrobiologia 95:115-126.

Effler, S.W. and D.A. Matthews. 2004. Sediment resuspension and drawdown in a water supply reservoir. Journal of the American Water Resources Association 40: 251-264.

Eiswerth, M.E., S.G. Donaldson, and W.S. Johnson. 2000. Potential environmental impacts and economic damages of Eurasian watermilfoil (Myriophyllum spicatum) in western Nevada and
northeastern California. Weed Technology 14(3):511-518.

Fox J., P.L. Brezonick, and M.A Keirn. 1977. Lake drawdown as a method for improving water quality. U.S. Environmental Protection Agency, Corvallis Environmental Research Laboratory, Corvallis, Oregon.

Fredrickson, L.H. 1991. Strategies for water level manipulation in moist-soil systems. U.S. Fish and Wildlife Service. Leaflet 13.4.6. 8 pp.

Furey, P.C., R.N. Nordin, and A. Mazumder. 2004. Water level drawdown affects physical and biogeochemical properties of littoral sediments of a reservoir and a natural lake. Lake and Reservoir Management 20: 280-295.

Furey, P.C., R.N. Nordin, and A. Mazumder. 2006. Littoral Benthic Macroinvertebrates Under Contrasting Drawdown in a Reservoir and a Natural Lake. Journal of the North American Benthological Society 25(1):19-31.

Gaboury, M.N. and J.W. Patalas. 1984. Influence of Water Level Drawdown on the Fish Populations of Cross Lake, Manitoba. Canadian Journal of Fisheries and Aquatic Sciences 41:118-125.

Glass, B.P. 1952. Factors Affecting the Survival of the Plains Muskrat Ondatra Zibethica Cinnamomina in Oklahoma. Journal of Wildlife Management 16:484-491.

Grime, J. 1977. Evidence for the existence of three primary strategies in plants and its relevance to ecological and evolutionary theory. American Naturalist 111:1169-1194.

Groen, C.L. and T.A. Schroeder. 1978. Effects of water level management on walleye and other coolwater fishes in Kansas reservoirs. American Fisheries Society Special Publication 11:278–283.

Hellsten, S.K. 1997. Environmental factors related to water level regulation-a comparative study in northern Finland. Boreal Environmental Research 2:345-367.

Hellsten, S.K. 2000. Environmental factors and aquatic macrophytes in the littoral zone of regulated lakes: causes, consequences and possibilities to alleviate harmful effects. Thesis, University of Oulu, Oulu, Finland.

Howard R.J. and C.J. Wells. 2009. Plant community establishment following drawdown of a reservoir in southern Arkansas, USA. Wetlands Ecological Management 17:565-583.

Hudon, C. 2004. Shift in Wetland Plant Composition and Biomass Following Low-Level Episodes in the St. Lawrence River Aquatic Vegetation: Looking Into the Future. Canadian Journal of Fisheries and Aquatic Sciences 61:603-617.

Hulsey, A.H. 1957. Effects of a fall and winter drawdown on a flood control lake. In: Proceedings of the annual conference southeastern association of game and fish commissioners 10:285-289.

James, W.F., J.W. Barko, H.L. Eakin, and D.R. Helsen. 2001. Changes in sediment characteristics following drawdown of Big Muskego Lake, Wisconsin. Archiv Fur Hydrobiologie 151:459-474.

Järvalt, A. and E. Pihu. 2002. Influence of Water Level on Fish Stocks and Catches in Lake Võrtsjärv. Proceedings of the Estonian Academy of Sciences. Biology and Ecology 51:74-84.

Johnsgard, P.A. 1956. Effects of water fluctuation and vegetation change on bird populations, particularly waterfowl. Ecology 37: 689-701.

Johnstone, I.M., B.T. Coffey, and C. Howard-Williams. 1985. The role of recreational boat traffic in interlake dispersal of macrophytes: a New Zealand case study. Journal of Environmental Management 20:263-279.

Keddy, P.A. and A.A. Reznicek. 1986. Great Lakes vegetation dynamics: the role of fluctuating water levels and buried seeds. Journal of Great Lakes Research 12:25-36.

Keto, A., A. Tarvainen, and S. Hellsten. 2006. The effect of water level regulation on species richness and abundance of aquatic macrophytes in Finnish lakes. Verhandlungen des Internationalen Verein Limnologie 29:2103-2108.

Klotz, R.L. and S.A. Linn. 2001. Influence of factors associated with water level drawdown on phosphorus release from sediments. Lake and Reservoir Management 17:48-54.

Korschgen, C.E. and W.L. Green. 1988. American wild celery (Vallisneria americana): ecological considerations for restoration (No. 19). US Department of the Interior, Fish and Wildlife Service.

Lantz, K.E., J.T. Davis, J.S. Hughes, and H.E. Schafer Jr. 1967. Water level fluctuation-its effects on vegetation control and fish population management. In: Proceedings of the Annual Conference Southeastern Association of Game and Fish Commissioners 18:483-494.

Madsen, J.D., L.W. Eichler, and C.W. Boylen. 1988. Vegetative spread of Eurasian watermilfoil in Lake George, New York. Journal of Aquatic Plant Management 26:47-50.

McEwen, D.C. and M.G. Butler. 2010. The effects of water-level manipulation on the benthic invertebrates of a managed reservoir. Freshwater Biology 55:1086-1101.

McGowan, S., P.R. Leavitt, and R.I. Hall. 2005. A Whole-Lake Experiment to Determine the Effects of Winter Drought on Shallow Lakes. Ecosystems 8(6):694-708.

Minnesota DNR (MN DNR). 2022. Wild celery (Vallisneria americana). .

Mississippi Interstate Cooperative Resource Association (MICRA). 2015. The use of grass carp in the United States. A report to the US Fish and Wildlife Service – Agreement #F12AP00630. .

Mjelde, M., S. Hellsten, and F. Ecke. 2012. A water level drawdown index for aquatic macrophytes in Nordic lakes. Hydrobiologia 704:141-151.

Murkin, H. R., R. M. Kaminski, and R. D. Titman. 1982. Responses of dabbling ducks and aquatic invertebrates to an experimentally manipulated cattail marsh. Canadian Journal of Zoology 60: 2324-2332.

Nelson, T. and M. Bowyer. 2000. Managing wetland vegetation for marshbirds and waterfowl. Final project report: FY00 Wildlife Preservation Fund, Eastern Illinois University, Charleston, Illinois.

New York State DEC (NYSDEC). 2005. A primer on aquatic plant management in New York State. NYSDEC Division of Water. Draft Report.

Nichols, S.A. and B.H. Shaw. 1986. Ecological life histories of the three aquatic nuisance plants, Myriophyllum spicatum, Potamogeton crispus, and Elodea canadensis. Hydrobiologia 131:3-21.

Paller, M.H. 2011. Recovery of a reservoir fish community from drawdown related impacts. North American Journal of Fisheries Management 17:726-733.

Perry, R. 1982. Muskrats. In: Wild Mammals of North America, J. Chapman and G. Feldhamer (Editors). John Hopkins University Press, Baltimore, Maryland, 1147 pp.

Radomski, P.J., T.J. Goeman, and P.D. Spencer. 1995. The effects of chemical control of submerged vegetation on the fish community of a small Minnesota centrarchid lake. Minnesota Department of Natural Resources, Section of Fisheries Investigational Report 442, St. Paul, Minnesota.

Reznicek, A.A., E.G. Voss, and B.S. Walters. 2011. Michigan Flora Online. University of Michigan.

Rogers, K.B. and E.P. Bergersen. 1995. Effects of a Fall Drawdown on Movement of Adult Northern Pike and Largemouth Bass. North American Journal of Fisheries Management 15:596-600.
Rørslett, B. 1989. An integrated approach to hydropower impact assessment. II. Submerged macrophytes in some Norwegian hydro-electric lakes. Hydrobiologia 175:65-82.

Siver, P.A., A.M. Coleman, G.A. Benson, and J.T. Simpson. 1986. The effects of winter drawdown on macrophytes in Candlewood Lake, Connecticut. Lake Reservoir Management 2:69-73.

Slade, J.G. 2005. Evaluation of fish-habitat relationships following a species-specific herbicide treatment in Minnesota. M.S. thesis, Mississippi State University, Mississippi State.

Smith C.G. and J.W. Barko. 1990. Ecology of Eurasian watermilfoil. Journal of Aquatic Plant Management 28:55-64.

Sutela T., J. Aroviita, and A. Keto. 2013. Assessing ecological status of regulated lakes with littoral macrophyte, macroinvertebrate and fish assemblages. Ecological Indicators 24:185-192.

Tarver, D.P. 1980. Water fluctuation and the aquatic flora of Lake Miccosukee. Journal of Aquatic Plant Management 18:19-23.

Tazik, P.P., W.R. Kodrich, and J.R. Moore. 1982. Effect of overwinter drawdown on bushy pondweed. Journal of Aquatic Plant Management 20:19-21.

Texas A&M. 2022a. How to control eelgrass: A diagnosis tool for pond plants and algae. .

Texas A&M. 2022b. How to control large-leafed pondweed: A diagnosis tool for pond plants and algae. .

Thomaz, S.M., T.A. Pagioro, L.M. Bini, and K.J Murphy. 2006. Effect of reservoir drawdown on biomass of three species of aquatic macrophytes in a large sub-tropical reservoir (Itaipu, Brazil). Hydrobiologia 570:53-59.

Thorp, J.H. and A.P. Covich, 1991. Ecology and Classification of North American Freshwater Invertebrates. Academic Press, San Diego, California, 911 pp.

Tomcko, C.M. and D.L. Pereira. 2006. The relationship of bluegill population dynamics and submerged aquatic vegetation in Minnesota lakes. Minnesota Department of Natural Resources, Investigative Report 538.

Trottier, G., H. Embke, K. Turgeon, C. Solomon, C. Nozais, and I. Gregory-Eaves. 2019. Macroinvertebrate abundance is lower in temperate reservoirs with higher winter drawdown. Hydrobiologia 834:199-211.

Turner, M.A., D.B. Huebert, D.L. Findlay, L.L. Hendzel, W.A. Jansen, R.A. Bodaly, L.M. Armstrong, and S.E.M. Kasian. 2005. Divergent Impacts of Experimental Lake-Level Drawdown on Planktonic and Benthic Plant Communities in a Boreal Forest Lake. Canadian Journal of Fisheries and Aquatic Sciences 62:991-1003.

Twinch, A.J. 1987. Phosphate exchange characteristics of wet and dried sediments samples from a hypertrophic reservoir. Implications for the measurement of phosphorus states. Water Resources 21:1225-1230.

University of Florida IFAS Center for Aquatic and Invasive Plants. 2021. Sections 3. Control Methods. .

Verrill, D.D. and C.R. Berry Jr. 1995. Effectiveness of an electric barrier and lake drawdown for reducing common carp and bigmouth buffalo abundances. North American Journal of Fisheries Management 15:137-141.

Voss, E.G. and A.A. Reznicek. 2012. Field manual of Michigan flora. University of Michigan Press, Ann Arbor, Michigan.

Wagner, T. and C.M. Falter. 2002. Response of an aquatic macrophyte community to fluctuating water levels in an oligotrophic lake. Lake Reservoir Management 18:52-65.

Wakeman, R.W. and D.H. Les. 1994. Optimum growth conditions for Potamogeton amplifolius, Myriophyllum spicatum and Potamogeton richardsonii. Lake and Reservoir Management 9:129-133.

Washington Department of Fish and Wildlife (WDFW). 2015. Aquatic plants and fish: rules for aquatic plant removal and control. Washington Department of Fish and Wildlife.

Weller, M.W. 1978. Management of freshwater marshes for wildlife. p. 267-284. In R. E. Good, D. F.

Whigham, and R. L. Simpson (eds.) Freshwater Wetlands, Ecological Processes and Management Potential. Academic Press, New York, NY, USA.

Weller, M.W. 1981. freshwater Marshes. University of Minnesota Press, Minneapolis, MK USA.

Weller, M.W. and C.S. Spatcher. 1965. Role of habitat in the distribution and abundance of marsh birds. Iowa Agricultural and Home Economics Experiment Station. Ames, IA. Special Report No. 43.

Wetzel, R.G. 2001. Limnology: Lake and River Ecosystems. Gulf Professional Publishing, Houston.

White, M.S., M.A. Xenopoulos, K. Hogsden, R.A Metcalfe, and P.J. Dillon. 2008. Natural level fluctuation and associated concordance with water quality and aquatic communities within small lakes of the Laurentian Great Lakes region. Hydrobiologia 613:21-31.

White, M.S., M.A. Xenopoulos, R.A. Metcalfe, and K.M. Somers. 2010. On the role of natural water level fluctuation in structuring littoral benthic macroinvertebrate community composition in lakes. Limnology and Oceanography 55:2275-2284.

White, M.S., M.A. Xenopoulos, R.A. Metcalfe, and K.M. Somers. 2011. Water level thresholds of benthic macroinvertebrate richness, structure, and function of boreal lake stony littoral habitats. Canadian Journal of Fisheries and Aquatic Sciences 68:1695-1704.

Wichelen, J.V., S. Declerck, K. Muylaert, I. Hoste, V. Geenens, J. Vanderkerkhove, E. Michels, N. DePauw, M. Hoffmann, L. DeMeester, and W. Vyverman, 2007. The importance of drawdown and sediment removal for the restoration of the eutrophied shallow Lake Kraenepoel (Belgium) Hydrobiologia 584:291-303.

Wilcox, D.A. and J.E. Meeker. 1991. Disturbance effects on aquatic vegetation in regulated and unregulated lakes in northern Minnesota. Canadian Journal of Botany 69: 1542-1551.

Deep Creek Lake Tributary Bioassessment

Deep Creek Lake Tributary Bioassessment

During July 2022, a team from PennWest – California and the Maryland Department of Natural Resources conducted a synoptic bioassessment of 29 perennial Deep Creek Lake tributaries at sites selected by the Deep Creek Watershed Foundation. Most stations were established as close to the lake confluence as accessible. The team obtained water samples, assessed fish and macroinvertebrate communities, and performed habitat evaluations. Four stations exhibited flows too low to permit fish or macroinvertebrate collection. Here only water samples were taken.

Three stations were accessed via boat. Overall, results describe cool water streams that exhibit measurable total alkalinity and generally possess good chemical water quality. However, poor habitat, including siltation and embedded stream bottoms, resulted in low macroinvertebrate and fish abundance.

This study serves as a preliminary baseline against which future monitoring and mitigation efforts of Deep Creek Lake tributaries may be evaluated. This study aims to identify potential projects that the Foundation can undertake to preserve and protect the watershed. The contract amount for this work is $13,125. The project partially fulfills Goal 3 of the Watershed Management Plan. We are working with DNR to identify new projects from the collected data.

Arrowhead Stream Biological and Water Quality Survey

Arrowhead Stream Biological and Water Quality Survey


Arrowhead Cove in the site of a pilot dredging project in Deep Creek Lake.  The Deep Creek Watershed Foundation is using this opportunity to conduct a biological and water quality survey of Arrowhead Run, a tributary to Deep Creek Lake.

The area of interest encompasses an approximately 0.4 mi. reach extending from a natural wetland at the upstream boundary to its confluence with Deep Creek Lake.  Two in-stream 100-m sampling stations will be designated and georeferenced – (1) below outflow of wetland; and – (2) above confluence with Deep Creek Lake where stream channel is well-defined. At each site a water sample will be collected, fish community composition will be determined by electrofishing, and macroinvertebrate community sampled by kick or sweep netting. An in-stream habitat evaluation score will be determined at each sampling site.  In addition, water samples will be collected above and below the wetland to determine its effect on downstream water quality, particularly nutrient and suspended solids loadings. A project summary will be prepared based on analyses described above that can serve as a baseline for future biomonitoring and bioassessment.

Water quality.  On-site measurements of temperature (C), pH, specific conductance uS/cm2 will be taken at the time of biological sampling at Stations 1 and 2.  A sample will be taken for analysis of total alkalinity (mg/l as CaCO3) in the laboratory at California University.  Samples will also be collected above and below the wetland and transported to a certified laboratory (H&H Water Controls, Carmichaels, PA) for analyses of nitrates, phosphates, and total suspended solids (TSS).

Habitat. In-stream habitat quality will be scored and presented for Stations 1 and 2 employing the US EPA’s Rapid Bioassessment methodology (Barbour et al. 1999).

Fish. The fish community at each Station will be sampled over each 100 m reach by back-pack electrofishing. All collected individuals will be identified to species, enumerated, and released.

Macroinvertebrates. Macroinvertebrate sampling will be conducted at each Station by kick or sweep-netting according to substrate characteristics (Barbour et al. 1999). All organisms will be preserved in 70% isopropyl alcohol and transported to California University for processing.  Organisms collected will be identified to the lowest practicable taxonomic level and enumerated.  

Assessment Summary. The status of resident fish and macroinvertebrate communities are recognized indicators of stream health. Data from water quality and biotic analyses will be integrated into a comprehensive report on the condition of Arrowhead Run and provide a baseline for future biomonitoring and assessment.

The Foundation is negotiating with the University to have conduct this research to establish a base line for the stream.  It is the Foundations wish to extend this work into all of the tributaries in the  Deep Creek Watershed.

The Foundation will be pleased to accept donations for this effort.  Go to the Donations page to do so.

Update: The Water Level Projects

Report to Donors to the Deep Creek Watershed Foundation:

The Water Level Projects

By David Myerberg

(This document is a deep dive into the problem, the role and success of the Foundation in its most expensive project to date.)


Deep Creek Lake property owners, renters and others need an adequate depth of water in the lake for recreational purposes. Every year, in the fall through the winter, the Deep Creek Dam operator releases water to prevent ice from damaging the dam and eroding the shoreline. In the spring, the dam releases less water and natural runoff causes the water to rise to the limit of 2461 feet above sea level. The spring/summer recreational season runs from April to October.

The dam operator follows a permit, issued by Maryland Department of the Environment (MDE) which specifies releases for hydroelectric generation, temperature enhancement for fish health in the Youghiogheny (at the warmest time of the year), white water boating opportunities in the Youghiogheny, and maintenance of minimum flows. The permit also defines an operating range for the lake’s water level, called the upper and lower rule bands. (See table, below.)

Defining the Problem: Competing interests

Some stakeholders are interested in releasing water from the dam and, of course, others are interested in keeping water in the lake to assure adequate depth for recreational boating.

The Dam Permit which governs water releases attempts to balance these competing interests. The permit is renewed every 12 years, but challenges to the permit can be submitted and addressed in the intervening years.

In 2010, lake residents experienced serious problems due to low seasonal precipitation and the fact that, during that season, the dam operator ran the lake levels near the lower rule band. This resulted in the water dropping below the lower rule band and led to both significant loss of dock usage, (especially in the shallow coves) and limitation of releases for whitewater runs in the Youghiogheny.

When the water level gets as low as the lower rule band, roughly two-thirds of the whitewater releases are suspended, leaving only the weekend releases. This substantially cuts into the whitewater businesses and activities which are headquartered in Friendsville, MD.

Another related issue occurs when the lake is left at a very high levels. At this time, there can be substantial erosion of the shore line in various areas. Barriers on the waterfront to prevent this erosion are limited. Traditionally, the cost of such barriers accrue to homeowners, despite the fact that the land on which such barriers are built is owned by the State. Although there is some movement by Maryland Department of Natural Resources (DNR) and MDE to make permitting for walls and rip-rap somewhat less expensive, the cost to the average homeowner of doing this work is exorbitant. Furthermore, the effect of leaving the water level high through the season has not been studied in Deep Creek Lake.

Following 2011, the dam operator realized their mistake and kept the water levels near the upper rule band during the season. Erosion of the shoreline from boat wakes and weather induced waves was not studied prior to or during this time.

Role that the Foundation Played regarding Low Water Levels

Some changes were made to the dam Permit on June 1, 2011, based on the problems with dock access and limitation of whitewater releases during the prior year, but, by no means did these changes address the potential of future problems with water allocation.

By the time the Foundation formed in 2016, through their work on the Deep Creek Watershed Management Plan, many on the Board and Advisors knew that neither MDE, who issues the permit, the Dam operator, the outfitters in Friendsville nor DNR/fisheries were agreeable to substantial future changes in the permit.

By funding pointed scientific study, the Foundation sought to help resolve the conflict among the stakeholders who use the lake water in very different ways.

What did we do?

Through a generous donation, the Deep Creek Watershed Foundation spent nearly $100,000 to address the issue of low water levels on Deep Creek Lake.

In 2007 and 2008, the US Geological Survey (USGS) and MDE had performed measurements of the depth of Deep Creek Lake along its entire 70-mile shoreline. This is called bathymetry analysis. In 2017-18, the Foundation hired an engineering firm to calculate the actual number of docks disabled by lowering water to certain levels from this bathymetry data.

The Foundation hired the same engineering firm to develop a Water Budget Model (WBM).[1] This was a “proof of principle prototype” that showed that one could predict when the water was going to approach the lower rule band and could adversely affect both whitewater activities and access to lake docks. If the water level drops close to the lower rule band, this WBM could warn the Dam operator to diminish releases and prevent a further drop in levels.

How did the Foundation’s investment in the WBM and the Bathymetric Analysis change the dynamic?

First, the Foundation prepared its campaign to change the permit more than a year before it was due for renewal. Second, the Foundation presented the WBM and the Bathymetric analysis to local legislators and governmental officers. This was well received. Third, the Foundation traveled to Baltimore to present the WBM and the Bathymetric Analysis to MDE, DNR and the Dam operator, to emphasize that the dam permit not only could be changed to the advantage of those who used the Lake’s water on its surface, but for those who use the water in the Youghiogheny River.

Fourth, Senator George Edwards arranged a meeting between the Foundation, the dam operator, MDE, DNR and representatives of the Governor’s office so the Foundation could present its grievances and solutions regarding the dam permit. Fifth, the Foundation (and representatives of the Property Owners Association and their lobbyist) met in Baltimore with John Grace, the point person at MDE for the permit renewal to further define the position of lakefront owners.

The studies enabled by the major donation allowed the Foundation to present irrefutable scientific evidence that if water levels were too low, a specific number of lakefront property owners were adversely affected. Likewise, the WBM was mathematically proven to be a method that would keep this from happening under most future scenarios. The Foundation was able to involve and convince local and State elected officials of these facts and to show the dam operator and MDE that there was some political will in Annapolis in support of needed changes in the permit and the permit process. All parties were involved and on-board early and helped to assure that the permit process in 2019 was going to be transparent and broad-based.

The Result

The 2019-2020 permit process was very different and much better than earlier permit stakeholder assemblies. The present Dam operator, Brookfield Renewable Power, funded three lunch meetings moderated by MDE for the stakeholders at WISP, in which Brookfield, lake stakeholders, whitewater interests and fisheries presented information. The Watershed Foundation’s President presented summaries of the Bathymetric and Water Budget Model studies. Question sessions were thorough. These meetings occurred from February through the fall of 2019 and a Comment Period occurred. A Public Hearing occurred by Zoom in October, 2020.

Following the Public Hearing, MDE issued the permit and a 36-page response to all formal comments/questions. John Grace told the Foundation’s President that when he started in this permit process at MDE, around 2000, there was no background material for him to read and no one who was unbiased to consult. The detailed process in 2019 enabled him to give comprehensive answers to every question raised by stakeholders which he hopes will provide a more complete background for future permit renewals.

In the 2020 Permit, the dam operator is required to adopt and use a predictive model [similar to the WBM] to keep track of the lake water levels through the recreational season. Likewise, the dam operator is required by tight specification to maintain the water level as close as possible to the upper rule band throughout the season.

Despite the fact that the POA and the Foundation felt that there needs to be a permit requirement for predicting potential breaches of the lower rule band and for taking specific corrective action using some kind of modified protocol, MDE would not go that far. We assume that they believe this would only happen in the worst drought conditions, which may be true.

The Foundation’s Future regarding Water Levels in Deep Creek Lake

First, the Foundation has funded a project by the USGS which installed a lake level meter. The Foundation has committed to continued funding of this meter so stakeholders (including the Foundation) can follow this important variable and will have accurate data for future study.[2] This tool also has a recording water temperature component paid for by the Foundation. This will be valuable to fishermen and to biologists interested in the semi-annual temperature inversion which is the exchange of bottom water and surface water due to warming and cooling of the surface.

Second, lakefront owners are concerned about erosion caused by maintaining the water level at high elevation through the season. Erosion is already addressed as a problem in the Foundation’s guiding document, the Deep Creek Watershed Management Plan. The accurate measure of water level funded by the Foundation will add another dimension to studies of lake shore erosion and the Foundation hopes to support the necessary studies to help bring this under control.

Third, if a protocol is developed by stakeholders and MDE that defines actions for allocation of lake water in the case of severe drought, the Foundation will help with these deliberations.


This chapter in the Foundation’s history shows what we can do with tax-deductible donations, thoughtful application of science and working in a sensible way with government and other stakeholders to the advantage of the lake and watershed.

The concept and development of the Water Budget Model was done in large part by Morgan France, now Director of Projects for the Foundation. The implementation of the permit requirements, and indeed the management of the water levels, are based on knowing what the water level is. That is not a simple measurement of water levels based on the current geodetic datum. The elevation of the water levels in the lake assumes that the overflow weir at the dam is at elevation 2462 in the permit, and in subsequent records. 2462 was the elevation that was determined at the time the dam was built. The difference between the lake datum (2462) and the current geodetic datum is about minus 1.8 feet. The current lake level gauge maintained by Brookfield is based on the 2462 datum. The readings from that gauge are available on the internet. However, this gauge is a “single point of failure” for the management process. The annual report for the preceding year is filed with MDE and available usually in February of the following year. The new recording lake level gauge sponsored by the foundation has daily real time lake level data retrievable back to August of 2020.

Do you have questions? Call or visit us.

(703) 975-8485

P.O. Box 376
Oakland, MD 21550


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