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Home , Fish ladder, Spillway

FREQUENTLY ASKED QUESTIONS

A. Fishway B. Riverwalk C. DNR Compliance with NR 333 D. Removal E. Property Issues F. Fish and Aquatic Life G. Wildlife H. Recreational Use

A. Fishway 1. What is the estimated cost to build a fishway at Bridge Street dam? The engineering consultant, Bonestroo, has estimated the cost at $1.3 million per the NOAA grant.

2. If the fishway is constructed next year, will it have to be rebuilt when the dam needs to be removed and replaced? Essentially no. Most of the fishway is a separate upstream structure and will not be impacted by demolition and construction of a new dam. The fishway entrance area may need to be modified if a new dam is installed or if the dam abutments are altered.

3. Why is the fishway being constructed on the west of the ? The west bank allows land owned by the Village of Grafton to be used for a portion of the alignment. Furthermore, the heaviest construction will likely be in the area currently owned by the Village (penetration of the west dam abutment). Other advantages include the appeal to tourists able to view fish entering and ascending the fishway from the riverwalk, and the known presence of shallow bedrock helping assure good foundation characteristics. Furthermore, the historic mill race crosses the area, and a portion of the mill race alignment may assist with fishway construction.

4. How long will it take to complete the construction of the fishway? The fishway will be completed by late fall of 2010.

5. How will the property owners adjacent to the fishway be impacted during construction? The riverwalk will be closed during the construction of the . Equipment and materials may need to be placed in the riverwalk area and the area between the riverwalk and the river. Any damage to this area would be fully restored as an integral part of the project.

6. Will additional property on either side of the dam need to be obtained to construct the fishway? No. The southern end of the fish passage will be constructed on property owned by the Village. The portions farther upstream will be constructed in or adjacent to the existing impoundment area.

7. What impact will building a fishway have on the riverwalk and the overlook area? The design of the fishway will include temporary removal of the overlook area. It is the Village’s desire and a fundamental project goal for the overlook area to be rebuilt and include a grate that will allow viewing of fish swimming up the fishway. Any damage to the riverwalk beyond the overlook area will be fully restored.

8. Who will own and be responsible for the maintenance of the fishway? The Village of Grafton.

9. Will the fishway reduce the flooding of the riverwalk in the ? The simple answer is “no.” Depending upon the ultimate design choices, however, the fishway may very modestly increase capacity, which may shorten the duration of the riverwalk flooding.

10. Is there a NOAA deadline for complying with the construction of the projects? By the end of October 2009, Ozaukee County must notify NOAA of the Village’s decision to either permanently remove the dam or install the fishway. All grant projects must be completed within the stipulated 18 month (December 2010) federal grant funding deadline.

11. What government agency will oversee the design and construction of either project? Ozaukee County is the lead agency for the NOAA grant. The Village will provide input to Ozaukee County.

B. Riverwalk 1. Will the riverwalk need to removed or moved if a fish ladder is constructed? The fishway will not displace the riverwalk. However, the riverwalk will need to be closed during construction. One of the project goals is to make fish movement through the fishway visible to the public on the riverwalk, adding a very significant feature to the downtown.

2. Will the riverwalk be moved closer to the new river’s edge if the dam is removed? No, the new river’s edge is expected to be within 15 feet of the existing river’s edge. However, a bedrock escarpment will likely be exposed near the dam, placing the riverwalk well above the flowing river elevation.

3. What are the costs associated with extending the riverwalk north or south? If the dam remains in place, engineering challenges make it impossible for the Village to extend the riverwalk.

If the dam is removed, the Village will be able to extend the riverwalk north of Washington Street and south of Bridge Street No estimates have been developed for the extensions. Funds from the NOAA grant can be used to offset the costs of a north riverwalk extension.

C. DNR Compliance with NR 333 1. What does the DNR require of the Village for the current dam? On July 16, 2009, the DNR notified the Village that they had made a determination that the Bridge Street dam has a “Significant” hazard rating. Per NR 333.07, the Bridge Street dam is required to have a 500-year or design capacity. It does not.

Chapter NR 333.04(2)(b) of the Wisconsin Administrative code states: “the owners of existing shall bring their dams into compliance with the requirements of this chapter within 10 years after being notified of the dam’s hazard rating pursuant to sub (1), unless ordered to do so earlier under s. 31.19(5), Stats.”

Consequently, DNR staff has informed the Village that the Village will have up to 10 years to comply with NR 333.07.

As part of the DNR notification, the Village is required to perform a spillway capacity study within one year: July 16, 2010. Based upon the outcome of the study, the DNR will identify the specific spillway capacity deficiency of the dam and a timeline to bring the dam into compliance. The existing dam is a fixed crest, weir-style dam. Because this makes it impossible to increase the spillway capacity, the Village will be required to construct a new dam in order to comply with NR 333.07.

2. Why are dams assigned a Hazard Rating? The DNR oversees certain dams in Wisconsin. The DNR must ensure that dams are designed, constructed, and reconstructed so as to minimize the danger to life, health, and property. NR333.04 of the Wisconsin Administrative Code requires the DNR to assign a dam hazard rating to all large dams based upon findings of a analysis, which are usually conducted by the owner of the dam.

3. What generated the determination of the dam rating by the DNR at this time? The DNR reissued a dam failure analysis for the Bridge Street dam as a part of the Ozaukee County Map Modernization Project in 2007. The DNR inspected the dam on August 26, 2008, and conducted a site visit on July 7, 2009. The DNR issued its Dam Inspection Report for the Bridge Street dam on July 13, 2009, and its Hazard Assignment Rating on July 16, 2009.

The DNR had previously issued an “apparent” hazard rating for the dam in September 1986. This was an estimate, however, and is not considered the formal Hazard Rating, which triggers the 10-year timeline for a spillway assessment.

4. What are the costs associated with the bringing the dam into compliance? Engineers have identified that the existing dam cannot be altered in order to meet NR 333.07. Consequently, the existing dam must be removed and a new dam constructed. The DNR estimated cost to remove the dam and construct a new dam is $4.0 million (in 2020 dollars). Additionally, the Village will need to devote operations and maintenance funds to keep the new dam in good working order and the dam’s gates in conformance with river flow. The Village should anticipate spending at least $100,000 every 10 years for this operations and maintenance effort.

5. What is the maintenance and costs to keep the existing dam for the next 10 years? The DNR-required engineering study will cost of $40,000. The study will evaluate the current structural condition as well as the spillway capacity deficiency. The study will also provide the Village with an update of the emergency action plan and create an operational and maintenance plan. In addition to this initial, comprehensive study, the recent revisions to State Statutes require an inspection to be completed three times within a ten year period. Typically, these inspections cost $8,000 to complete.

6. Has the Village initiated the update of the emergency action plan of the existing dam as required by the DNR to be completed by the end of 2010? No, the plan will be completed as part of the engineering study that will be done by July 2010. If the dam is removed, the emergency action plan will not be needed.

D. 1. What is the pollutant content of in the Bridge Street dam impoundment? Sediment samples were collected from the impoundment and analyzed for a variety of potential organic and inorganic chemical pollutants including polychlorinated biphynels (PCBs), polynuclear aromatic hydrocarbons (PAHs) and heavy metals (e.g., lead). The results were compared to a range of criteria, and it was concluded that the do not pose a threat to human health and the environment.

2. How will the sediments be managed in the Bridge Street dam impoundment area should the dam be removed? Sediments can safely be managed within the Bridge Street dam impoundment using a variety of bioengineered (e.g., native plants), engineered (e.g., rip rap), or combination of techniques.

Depending on spring-summer weather conditions, it is possible for plants to begin growing as soon as one month after the exposed sediment dries sufficiently. It will take up to two years for sediments to fully consolidate (compact) and return to a natural landscape. Consolidation of soils is typically 25 percent.

3. Will the removal of the dam reduce the frequency of the flooding of the riverwalk in the spring? Yes.

4. In the concept plan that shows the new channel of the river, a small pond is identified at the northeast corner of Veterans Memorial Park. Why? If the dam is removed, the Village has an opportunity to create a management pond which brings the Village into closer compliance with DNR stormwater permit requirements. The cost to construct this pond may be eligible for NOAA funds up to the allocated grant limit. The Village’s cost to build a DNR-required pond in another location is estimated to be $760,000.

5. If a decision is made to remove the dam, what related project costs are eligible for funding under the NOAA grant? In addition to the dam removal, riverbank restoration (including the possible extension of the riverwalk), stormwater management pond, clean-up, restoration and landscaping of newly exposed riverbed and channel (i.e. grass, wildflowers, trees, shrubs), restoration of the boat launch, and additional public and handicapped access points can be funded up to the allocated NOAA funding limit.

6. Will the existing short retaining wall on the west side of the river adjacent to the existing riverwalk be removed as part of the restoration? Yes.

7. Exactly where will the river flow when the dam is removed? The river will return to its pre-dam channel over time. Some areas, especially near the dam, will return to the pre-dam channel immediately after dam removal. The future channel in the area between Washington Street and the dam will likely hug the west bank and will be confined by bedrock escarpments. Current velocities will be rapid through this area, and there will likely be a series of bedrock shelves exposed. During higher water periods, a will likely develop. Areas upstream of Veterans Memorial Park will see the river narrow progressively upstream. At Veterans Memorial Park, the channel is anticipated to narrow by less than 20 percent. The impoundment near Park will narrow, but flow will be maintained through both the main and secondary channel. All channel width changes will cease about midway between River Island Park and the Ozaukee Interurban Trail bridge.

8. In comparison to the current width of the Milwaukee River at the Washington Street Bridge, what will be the estimated width of the river if the dam is removed? The section of the river adjacent to and south of the Washington Street Bridge originally appears to have run through a bedrock gorge. The river channel width will decrease substantially in this fast flowing area. Consequently, we anticipate the river channel to be approximately 75 feet wide under the bridge, compared to the impoundment width of approximately 260 feet.

The areas upstream of Veterans Memorial Park which will not see large changes in channel width.

9. If the dam is removed, what amenities for the community can be constructed on the newly exposed river beds? The Village Board would ask the community for input on amenities for the areas that are adjacent to the existing Village park properties. The Parks and Recreation Board would subsequently develop concepts for the public’s review. With remaining funds from the NOAA grant, amenities could include a stormwater pond that would also serve as an ice skating area, canoe/kayak launches, fishing piers, handicap access and fishing areas, boat launches, an extended riverwalk, and additional picnic areas.

E. Property Issues 1. If the dam is removed, who will own the dry land created should the width of the river recede? The process of water receding to expose land is called “reliction.” When soil is uncovered by reliction, the owner of the land adjacent to the newly-created soil obtains right and title to the soil. See Doemel v. Jantz, 180 Wis. 225, 235 (1923), Heise v. Village of Pewaukee, 92 Wis. 2d 333, 336 (1979). The State owns and holds all waterways in trust for the public up to the ordinary high water mark. See Illinois Steel Co. v. Bilot, 109 Wis. 418, 425 (1901).

The Village has conducted an extensive title search regarding the ownership of the dam as well as the ownership of any land that will be uncovered by reliction should the Milwaukee River recede. There is a clear chain of title indicating that the Village owns the dam. However, there does not appear to be any evidence suggesting that the Village or any prior owner of the dam owns the land in the impoundment that was covered by water after the dam was constructed. Therefore, the adjacent landowner would take title to this land as explained above.

2. What is the ordinary high water mark? The Wisconsin Supreme Court has defined the “ordinary high water mark” as “the point on the bank or shore where the water, by its presence, wave action or flow, leaves a distinct mark on the shore or bank.” See State v. Trudeau, 139 Wis. 2d 91, 408 N.W. 2d 337 (1987). The ordinary high water mark may be indicated by , destruction of vegetation, changes from aquatic to terrestrial vegetation, or other characteristics. The ordinary high water mark does not always equate to the water’s edge. The DNR is responsible for determining the ordinary high water mark.

3. As a property owner of the newly exposed riverbed, what can I do with the newly exposed property? There are no restrictions on how the newly created and exposed sediment/soil can be used. Private property owners may prefer to maintain ownership or transfer ownership to a public entity for public use. Private uses could include extension of lawns, gardens, etc. Property owners must avoid the planting of any trees or shrubs that would result in the creation of a natural wall/fence. Property owners can regrade the area. Since the newly exposed lands will likely remain in the , filling or construction activities would have to meet the Village of Grafton’s existing floodplain ordinance.

F. Fish and Aquatic Life 1. What are the goals for constructing a fishway or removing the Bridge Street dam? The objectives for passing fish upstream of the Bridge Street dam include: a. Enable fish passage to historical fish spawning and rearing habitats for river, , and Lake Michigan fish populations, including game, non-game, endangered, threatened and special concern species. b. Increase the probability of restoring sustainable populations of lake sturgeon and walleye to the Milwaukee River, its estuary and Lake Michigan currently managed through artificial rearing and stocking programs. c. Increase fish stock genetic diversity. d. Increase recreational fishing opportunities for the state’s most populated and demographically diverse river basin.

Either construction of a fishway while maintaining the Bridge Street dam and impoundment or removing the Bridge Street dam would meet the objectives for passing fish beyond the Bridge Street dam.

2. How would the fishway or dam removal alternative benefit or impact local fish and aquatic life and their habitat? Prior to development, fish and aquatic life along the Milwaukee River evolved in free-flowing habitats. The Milwaukee River native fish community includes over 60 species. While some adapted to both lake and river habitats, many need river or habitats for all or part of their life cycle.

The Bridge Street dam fishway will not alter existing impoundment habitat. The fishway alternative would simply pass fish upstream of the dam. Some fish will remain in the impoundment, but most will be transient and pass through it to preferred habitat (e.g., trout and lake sturgeon). Some fish will be more efficient and frequent users of the fishway than others. Habitat in the Bridge Street dam impoundment is limited by excessive buildup of silt (up to 7-feet thick), nuisance plant growth (e.g., duckweed), turbid and warmer summer water temperatures. It is generally more conducive to fish and aquatic life tolerant of degraded habitat (e.g., carp and bullhead, midge and “sludge worms”). Game fish (northern pike, smallmouth bass) will remain but in limited numbers. Greater numbers and are present in the top of the impoundment where habitat is more river-like than pond. Habitat will continue to degrade as natural and man-made sources of sediment, death and decay of aquatic plants continue to fill in the impoundment.

Removal of the Bridge Street dam would significantly alter habitat in the Bridge Street impoundment. The habitat would change from a shallow, fine-textured (clay, silt and sand) pond-like habitat to that of a variable depth, coarse-textured (gravel-cobble-bedrock) riverine habitat. Habitat would be more conducive to fish and aquatic life less tolerant of degraded habitat (e.g., redhorse and smallmouth bass, caddisfly and mayfly). Water quality would improve over time with cooler summer water temperatures, lower turbidity and less nuisance growth of aquatic plants. Changes toward river-like features would be dramatic in the short term (one year) and more ideal river habitat would evolve from one to five years, similar to what occurred along the river following removal of the Chair Factory dam just downstream.

If planned fishways or dams are removed at the Thiensville-Mequon dam, Lime Kiln dam and Bridge Street dam, fish movement will be unimpeded along 90 miles of river and perennial , intermittent . Fish will also have access to thousands of acres of wetland between the Thiensville-Mequon dam, the Milwaukee River estuary and Lake Michigan.

The impacts and benefits of dam removal on fish communities in Wisconsin have been studied and published in peer reviewed journals. These dam removal river studies included the Baraboo River and Milwaukee River. In all instances, the effects on fish and aquatic life habitat were positive following dam removal.

3. What are the potential impacts of the fishway and dam removal alternatives on the potential spread of invasive animal and plant species? Plant and animal invasive species are a problem for native ecosystems throughout North America, including the Great Lakes ecosystems. Locally within the Bridge Street dam impoundment and Milwaukee River watershed, Eurasian water milfoil, purple loosetrife, reed canary grass, and carp are some of the most frequently encountered plant and animal species. Zebra mussels, common to the Great Lakes, are known to exist in some of the Milwaukee River basin’s headwater lakes (e.g., Big Cedar and Long Lakes). Water resource management agencies are concerned about the potential upstream movement of sea lamprey and fish diseases (VHS) from Lake Michigan.

Sea lampreys have never been documented in the Milwaukee River basin since monitoring began in 1959. No one knows for certain why sea lampreys do not utilize the Milwaukee River; perhaps habitat is not conducive for their reproduction.

VHS can infest native as well as non-native fishes. Unlike sea lamprey, VHS sources of infection can come from sources downstream or upstream of the Bridge Street dam. VHS has been identified from Lake Michigan . At the time of preparing this document, VHS has not been identified in the Milwaukee River basin.

If a fishway is constructed, the fishway will include any number of mechanical devices that would enable resource managers to either close down the fishway (e.g., flashboards) or a “trap and sort” device that would enable managers to sort through fish moving through the fishway, allowing natives to move upstream while capturing and destroying invasive species.

Should the Bridge Street dam be removed, there would be no device that could prevent passage of fish upstream. Instead, the fishway currently being constructed at the Thiensville-Mequon dam will include a moveable gate to close down the fishway, and/or a “trap and sort” device would be constructed to capture invasive species. The Thiensville-Mequon dam is not a complete barrier to fish movement.

The Bridge Street dam fishway and dam removal alternative will require the preparation of an Environmental Assessment (EA). The EA and associated permits would be public noticed for review and comments.

G. Wildlife 1. What are the impacts of constructing a fishway or removing the Bridge Street dam on wildlife and their habitat? Locally, the best model for predicting the impacts of constructing a fishway or removing the Bridge Street dam comes from an assessment of the Milwaukee River’s North Avenue dam project. Based on that assessment, construction of a fishway would not change the wildlife community or their habitat in the short- term. In the long-term, wildlife habitat will be modified as the impoundment continues to fill in by sediment. In some instances, as sediment accumulates in upper reaches of the impoundment, new floodplain lands may be created. Removal of the Bridge Street dam would have the most dramatic affect on wildlife and their habitat. Overall, habitat conditions would improve for the most common bird species, including raptors. The extent of those benefits would depend on the re-vegetation plan and cover types (e.g., grass/forb, shrub, wooded) that develop along the exposed sediment/soils. Removal of the dam and resulting impoundment would decrease the amount of open water and loafing habitat for some species, most notably diving ducks. Some other bird species, such as wading birds (e.g., blue heron) may benefit from the greater length of shoreline and water’s edge that will develop for feeding purposes. No mammals are expected to be displaced by removal of the dam. Since most mammal species are terrestrial, they may benefit by the additional amount of floodplain that will develop. The diversity of common amphibians and reptiles (collectively called herptiles) would not be negatively impacted by removal of the dam. Newly created floodplain would provide suitable feeding and nesting sites. Turtle numbers are not expected to noticeably change. Newly exposed floodplain soils will be used for basking and egg laying sites.

H. Recreational Use 1. Will dam removal preclude summer and winter sport activities? Ice skating will no longer be available on the river adjacent to the Washington Street bridge. Additional ice skating opportunities could be created on publically owned land such as the proposed stormwater pond near the north edge of Veterans Memorial Park.

Boating opportunities will change in areas near the dam, but will not significantly change at areas near River Island Park and upstream. The deeper water areas near the dam will be supplanted with reaches that are very conducive to kayaking and canoeing.