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HomeMy WebLinkAbout2008.07.09 - Email from Richard Mraz of Ecology to John McDonaghWetland 3rd Party review Pat lolavera Page 1 of6 From: John McDonagh Sent: Wednesday, JulY 09, 2008 3:05 PM To: Pat lolavera Subject: FW: Wetland 3rd Party review for Hastings Road site Earu b From : Mraz, Richard A. (ECY) [mailto: rmra46 1@ECY.WA'GOV] Sent: Wednesday, April 09, 2008 12:59 PM To: John McDonagh Cc: Judy Surber; westech@westechcompany.com; wdploggy@olypen.com; Lund, Perry (ECY) Subject: FW: Wetland 3rd Party review for Hastings Road site Hello John, I attach my previous e-mail to provide context for this further discussion. I first became involved with this site inAugust 2007 as 3rd party reviewer of a delineation and rating by Mr. David Loggy' You recently proviled me with urroth.t field review, conducted by Westech Co.,_o_f.the site in question on Hastings Road. This latest investigation occurred in February and March of this year and found none of the ovJrt hydrologic evidence described in the e-mail below. As a result, Westech's rating was a Category IV (similar to Mr. Loggy's conclusion) since the wetland did not score as high for hydrologic storage, water qualrty or habitat functions. As I discussed in the earlier e-mail, when one visits a wetland, it must be rated based on the conditions present at the time of rating. As noted below, when I visited the site, there was sufficient evidence of iong-term inundation to reach certain conclusions about depth and duration of inundation. Extensive algil mats were present. Algal deposits are most often seen in seasonally ponded depressions, inlerdunal swalds, tidal areal, hke fringes, and low-gradient stream margins. They reflect prolonged wet conditions sufficient for algal growth and development, generally 2 to 3 months. In his revised report, it was suggested by Mr. Loggy that the hydrology for the site-was atypical. Rainfall data fof the previous 5 years do not appear to indicate that the unusual hydrology was precipitation driven. It was also suggested thifrecent ditch maintenance may have recently introduced a iurg" .rolu-e of water into the site. Based on the recent series of investigations, including a bnef visit thai I conducted on April4, 2008, the hydrology I observed back in2007 may, in fact, be atypical. It does appear that a large volume of water (the evidence of which I noted) may occasionally enter and reside in ftris wetland. Il certainly happened some time in2007. Whether this was a unique event or will occur with some regularity is difficult to say. As I suggested below, "one option to confirm this possibility would be to monitor the wetland and collect hydrology data over the next several years". i{o*"r,'"t, I acknowledge that this may not be practical and may work contrary to both the property owner's and the City's interests. The source of the seasonal ponding in this wetland is likely a large "slug" of water that enters the depression after moving through a series of ditches that connect with other wetlands. The timing and frequency of such utt oc"*tett"e is difficult to predict and may (as Mr. Loggy suggested) be a result of rprt "u* maintenance activities. During my most recent observation I noted that the upstream, offsite drainage ditch was holding a large volume of water (almost bankfull) while the onsite ditch had only 2- 71912008 Wetland 3rd Party review Page2of6 , 4" of water and the ditch in the wetland was only saturated at the surface. The primary hydrologic inputs into this system are manipulated and unpredictable. The current prevailing evidence appears to indicate that seasonal ponding is less frequent than the conditions observed in August 2007. To know for certain, the site would have to be monitored for evidence of seasonal ponding in 5 out of l0 years (question D 1.4 on the rating form). However, I will concur that the "normal" conditions that exist in this wetland are accurately represented by the Category IV rating provided by Dr. Shea and Mr. Loggy. I agree that the soils on the fringe of the wetland do not exhibit characteristics of seasonal ponding. I would note that it is likely the wetland will continue to occasionally contain water of sufficient depth and duration as that which caused algal mat formation. The City should consider this possible condition is reviewing any "downstream" proposals or proposals to alter this wetland. Please let me know if you have any questions or require clarification of these statements. Rick Mraz Wetlands,/Shorelaods Specialist SLorelarrds and Environmental Assistance Pro{lram Southwest Regional O(ice 500)407-6nt r-ra4Ol@ecv.wa.{lov From: Mraz, Richard A. (ECY) Sent: Friday, August 3L,2007 9:21 AM Toi 'Suzanne Wassmer' Cc: Judy Surber; Lund, Perry (ECY) Subject: RE: Wetland 3rd Pafi review Suzanne The primary issues on which the rating hinges are the extent and duration of ponding within the wetland. lhe supplemental work by Loggy cites rainfall values and infers ponding characteristics within the wetland. The report notes that rainfall levels in recent years cannot be cited as having caused increases in the wetland hydrology. The suggested cause is recent dirch maintenance, which is purported to have innoduced additional water into the subject wetland. Also, the possibility of a blockage of oudlow was mentioned. 'fhe presence of a recently maintained ditch provides an interesting aspect to this situation. It could be argued that when the ditch was regularly maintained, the subject wetland was larger in size. Once ditch maintenance lapsed, the wetland hydrology diminished. However, soils in the areas of the most landward extent of the mats also evinced hydric character. These features are less temporal and suggest that such pondingas was observed during my visit is a normal circumstance. Given the information provided, it is not possible to conclusively assert that the hydrology that I observed is alypical. When one visits a wetland, it must be rated it based on the conditions present at the time of rating. I acknowledge that Mr. Logy did not encounter the conspicuous algal mats during his visir However, this does not change my conclusion that the wetland at the time of my inspection was larger than the delineation. I make this assertion based not only on the presence of algae mats but the presence of 71912008 Wetland 3rd Party review Page 3 of6 hydric soils. The algal mats and amphibian population, which indicate larger areal and longer duration inundation may reflect the new normal circumstances. If legal ditch maintenance has re-established a certain level of hydrology to this system, then this can be considered the new normal circumstance. One option to confirm this possibility would be to monitor the wetland and collect hydrology data over the next several years. it{hile the wetland is a Category III, it is a very low function III (32 points total,wf t habitat points). It could benefit significantly from enhancement. I note that Port Townsend's Critical Areas Ordinance allows for buffer reduction when enhancement is implemented. This wbtland seems to be a candidate for that approach. Please let me know if you have any questions or require clarification of these statements. Rick Mraz Wetla"ds,/Shorelaods Specialist Shorelands and Enwironmental Assistance Pro5lram Southwest Re5ional Of{ice 500\407-on| rmra40l@eca.wa.{lov From: Suzanne Wassmer [mailto:swassmer@cityofpt.us] Sent: Tuesday, August 28,2007 9:30 AM To: Mraz, Richard A. (ECY) Subject: RE: Wetland 3rd Pafi review OK, thank you! please see attached. ln addition to the Loggy report I have included a couple of pages from owner Carol Wise, and a letter from the former resident of the property who apparently lived there 60+ years. Suzanne Original Message---- From: Mraz, Richard A. (ECY) [mailto: rmra461@ECY.WA.GOV] Sent: Tuesday, August 28,2007 9:15 AM To: Suzanne Wassmer; JudY Surber Cc: Lund, Perry (ECY) Subject: RE: Wetland 3rd Pafi review Hi Suzanne, I will be glad to review the additional materials prepared by Loggy Soil and Wetland Consulting. Sending the information by e-mail would be best and would allow me to provide the quickest reply. Rick Nkaz Wetlaods/Shorelaods Special ist Shorelaodt and Enwironmental Assistance Pro{tram 71912008 V/etland 3rd Party review Page 4 of6 Southwest Re6lional O{{ice 360j407-O?, | rmra4Ol@ecu.wa.{tov From : Suzanne Wassmer [mailto : swassmer@cityofpt. us] Sent: Tuesday, August 28,2007 9:09 AM To: Mraz, Richard A. (ECY); Judy Surber Cc: Lund, Perry (ECY) Subject: RE: Wetland 3rd Pafi review HiRick, This email is in regards to the Gammage Estate site that you visited with us June 20, 2007. Attached is a recent letter sent to the owner of the property that gives some explanation about what has happened since the site visit. The owners of the property are questioning the Category lll rating. We're wondering if you are available to review materials prepared by Loggy Soil and Wetland Consulting. His report discusses how the neighboring property could have affected the Gammage Estate and wetland rating. lf you are available, please let me know your schedule and the best way to forward materials to you (email, fax, mail?) Thank you! Suzanne Original Message----- From: Mraz, Richard A. (ECY) [mailto:rmra461@ECY.WA.GOV] Sent: Monday, July 02, 2007 B:41 AM To: Judy Surber Cc: Suzanne Wassmer; Lund, Perry (ECY) Subject: Wetland 3rd Party review HelloJudy, I vwite to summarize my review of the wetland delineation and rating for the Gammirge Estate site. These comments are offered in consideration of our site visit, conducted onJnne 20,2007 and anoffice reviewof awetlanddelineationandratingreportmade by Loggy Soil and Wetland Consulting. The reportis dated September 25,2006. I will address the delineation first and in doing so I will refer to Figure 2, the location/description map in the delineation report. During our site visit, I located many of the te st holes reported on Figure 2 and dug additional holes in areas that were identified as outside the delineated wetland. In general, I found that the wetland was larger than indicated on Figure 2. I assert this because several of the areas where I dug tests holes ouLside of the delineated wetland, met the three wetland pirameters, which are: presence of hydrology, hydric soils and a dominant hydrophytic vegetation community. Specific areas where the wetland is underrepresented are as follows: West-northwest of test hole #6 - this area displayed hydric soils: 10YR 2l2 wrth 2- 20% distinct redoximorphic features (7.5YR 3/4). Ttre soil was saturated at a depth of 8" at the time of investigation. Algal mats were present on the surface and suspended in the vegetation at a height of 8-10" above the surface. This area was vegetated 719t2008 Wetland 3rd Party review primarily with reedcanarygrass (Phalaris arundinacea, FACW), but also contained areas of Nootka rose (Rosa nutkana, FAC). The wetland extends further west and northwest at least 15-20 feet. East of test hole #3 - This area displayed hydric soils: 10YR 2/1. The soil was saturated at a depth of 8". Algal mats were present on the surface and suspended in the vegetation at a height of 1' above the surface. Vegetation was similar to the area west of test hole #6 but a greater percentage of Nootka rose was present. The area vegetated primarily with Nootka rose and generally west-northwest of test hole #8 may also be primarily wetland. There is litde if any change in contour and elevation from this area to the reedcanarygrass-domianted wetlands west of test hole 6. The area is so densely vegetated with this thorny rose that we could not investigate the soils without sig'nificantly more time . Areas where I concur with the delineation are as follows: Test hole #12 is accurate. Testhole #10 is accurate. Regarding the consultant's rating of the wetland, several changes are necessary that affect the rating score. The evidence of ponding is greater than represented in the rating. This factor affects the water quality, hydrologic and habitat functions scores. The presence of algal mats at 8-12" above the surface indicates that significant ponding occurs within the wetland. In consideration of the extent of the algal mats, it is apparent that at least 1/4 of the total area of the wetland is seasonally ponded (Question D 1.4 on rating form). The height of the mats demonstrates that the wetland stores water at depths between 0.5 f-eet to 12 feet (Question D 3.2 on rating form). In add.ition, during our visit at least a dozen very small pacific chorus frogs were seen in the lowest area of the wetland. These frogs have a life history that requires approximately three months of ponding (avg. 37 days for egg laying and harch + 2-2.5 month larval stage). In consideration of the above indicators, another hydroperiod exists (Question H 1.2) that is seasonally flooded or inundated. The habitat score is also increased in consideration of question H2.4. Based on analysis of NWI and GIS mapping, combined with our exploration of adjacent properties, there are three wetlands within a U2mtrebutthe connection between them are disturbed. Regarding the habitat score, I noted errors in the addition in that section. Explanation of these errors is complicated and I have provided details in a phone conversation with you. The result of these errors is that, with the addition of another hydroperiod and notation of other wetlands in the area, the habitat total is 9 points, which is the amount repor[ed by the consultant. Page 5 of6 71912008 Wetland 3rd Parly review Page 6 of6, The ultimate result of the additional points for water quality and hydrologic function, in combination with the correction of scores for habitat function, is that the wetland scores 32 points and is a Category III. Thank you for the opportunity to assist the City of Port Townsend. I hust that this review and conclusion is useful for your purposes. If you have any questions or require clarification of,these statements, please contact me. Rick lvkaz Wetla"ds/Shorelands Specialist SLorelands and Environmental Assistance Pro5lram Southwest Regional O(ice 5001407-o?pt rmra4Ol@ecu.wa€ov 7/912008