The hydraulics and resulting bed scour within the vicinity of Submerged Single Span Arch Bridges

As a consequence of climate change there is now a more frequent occurrence of extreme rainfall events where, with higher rates of urbanisation, the built environment has become increasingly affected by flooding.. This is of particular importance in relation to the stability of bridge structures that span rivers and canals etc. In November 2009, the UK and Ireland were subjected to extraordinarily severe weather conditions for several days. The rainfall was logged as the highest level of rainfall ever recorded within the UK, and as a direct consequence, unprecedented flooding occurred in Cumbria. This flooding led to the collapse of three road bridges which were generally 19th century masonry arch bridges, with relatively shallow foundations. In the UK, knowledge of the combined effect of bridge scouring and inundation has been not been particularly widely studied. Research carried out by Hamill et al [1] considered the hydraulic analysis of single arch bridges under flood conditions, but no consideration was given towards the likely damage to these structures due to scouring. Prior to this, Bierry and Delleur [2] produced a classic paper in predicting the discharge downstream of an inundated arch, focussing on predicting afflux as opposed to bridge scour. Further work on backwater effects was carried out by Martin-Vide & Prio [3] in semi-circular arch bridges. Both pressurized and free-surface flows at the bridge were investigated. Flows on a mobile bed in clear-water conditions were compared to those with a rigid bed, but no predictive equation for scour under pressurised conditions was considered. This paper will present initial findings from an experimental investigation into the effects of surcharged flow and subsequent scour within the vicinity of single span arch bridges. Velocities profiles will be shown within the vicinity of the arch, in addition to the depth of clear water scour, for a series of flows and model spans. The data will be presented, where results will be correlated to the most recent predictive equations that are proposed.

Comment on ''Sedimentary DNA from a submerged site reveals wheat in the British Isles 8000 years ago''

Smith et al. (Reports, 27 February 2015, p. 998) identify wheat DNA from an 8000-calendar-years-before-the-present archaeological site in southern England and conclude that wheat was traded to Britain 2000 years before the arrival of agriculture. The DNA samples are not dated, either directly or from circumstantial evidence, so there is no chronological evidence to support the claim

Detecting Submerged Macrophytes in a UK Chalk Stream Using Field Spectroscopy

Various studies using optical remote sensing in the marine environment have shown the possibilities of spectral discrimination of benthic macro and micro-algae. For in-land water bodies only very recently studies of have explored similar use of optical remote sensing to identify the taxonomic composition of algae and rooted plant communities. The importance of these communities for the functioning of river ecosystems warrants further research. In the study presented here, field spectroscopy is used to assess the possibilities of optically detecting macrophytes in a UK chalk streams. Spectral signatures of four common macrophytes were measured using a hand-held GER1500 spectroradiometer. Despite the strong absorption of near infrared in water, the results show that information on NIR can clearly contribute to the detection of submerged vegetation in shallow UK chalk stream environments. Observed spectra compare well with simulated submerged vegetation spectra, based on water absorption coefficients only. The field investigations, which were performed in the river Wylye, also indicate the confounding effects of specular reflection from riparian vegetation. The results of this study can inform remote sensing studies of the riverine environment using multi-spectral/low altitude sensors. Such larger scale studies will be highly beneficial for monitoring variation in chalk stream bioindicators, such as ranunculus.

Quantifying Submerged Fluvial Topography Using Hyperspatial Resolution UAS Imagery and Structure From Motion Photogrammetry.

Quantifying the topography of rivers and their associated bedforms has been a fundamental concern of fluvial geomorphology for decades. Such data, acquired at high temporal and spatial resolutions, are increasingly in demand for process-oriented investigations of flow hydraulics, sediment dynamics and in-stream habitat. In these riverine environments, the most challenging region for topographic measurement is the wetted, submerged channel. Generally, dry bed topography and submerged bathymetry are measured using different methods and technology. This adds to the costs, logistical challenges and data processing requirements of comprehensive river surveys. However, some technologies are capable of measuring the submerged topography. Through-water photogrammetry and bathymetric LiDAR are capable of reasonably accurate measurements of channel beds in clear water. Whilst the cost of bathymetric LiDAR remains high and its resolution relatively coarse, the recent developments in photogrammetry using Structure from Motion (SfM) algorithms promise a fundamental shift in the accessibility of topographic data for a wide range of settings. Here we present results demonstrating the potential of so called SfM-photogrammetry for quantifying both exposed and submerged fluvial topography at the mesohabitat scale. We show that imagery acquired from a rotary-winged Unmanned Aerial System (UAS) can be processed in order to produce digital elevation models (DEMs) with hyperspatial resolutions (c. 0.02 m) for two different river systems over channel lengths of 50-100 m. Errors in submerged areas range from 0.016 m to 0.089 m, which can be reduced to between 0.008 m and 0.053 m with the application of a simple refraction correction. This work therefore demonstrates the potential of UAS platforms and SfM-photogrammetry as a single technique for surveying fluvial topography at the mesoscale (defined as lengths of channel from c.10 m to a few hundred metres). This article is protected by copyright. All rights reserved.

Pass charta öfver n[or]ra delen af Östersjön, Ålands haf med s[öd]ra delen af Botten-Hafwet

Graverad af E. Åkerland

Principles and proceedings of the inhabitants of the District of Niagara for addressing His Royal Highness the Prince Regent, respecting claims of sufferers in war, lands to militiamen and the general benefit of Upper Canada. --

Cover title.

Welland Canal Survey of Lands Name Index Page 2

Index of names for the Welland Canal Company's Survey of Land book, 1826. Includes persons name, land cultivated, uncultivated, total land and remarks. The remarks noted include; who surveyed the lands, the dates of the survey, former property names, additional property features etc.The page is titled: Statement of Lands Surveyed and appropriated to the use of the Welland Canal Company.

Welland Canal Survey of Lands Name Index Page 4

This is an index of all the names contained within the Survey of Lands. The names are listed in alphabetical order and are paired with page numbers where more information can be found on the individuals listed. This page lists names beginning with "A" through to an including "N".

Welland Canal Survey of Lands Name Index Page 5

This is an index of all the names contained within the Survey of Lands. The names are listed in alphabetical order and are paired with page numbers where more information can be found on the individuals listed. This page lists names beginning with "O" through to an including "Z".

Welland Canal Survey of Lands Nathan Pawling 1826; includes map and text.

Survey map and description of Nathan Pawling's land created by The Welland Canal Company. Included is a written description of the land along with a drawing of the land. Noteable features include; the dock, pier and tow path. The original bed of 12 mile creek is also noted on the map. Surveyor notes are seen in pencil on the map. The map notes the division of land between Pawling and Robert Brown's land. Click on 'detail' to see Map.

Welland Canal Survey of Lands James Gordon

Survey map and description of James Gordon's land created by The Welland Canal Company. Included is a written description of the land along with a drawing of the land. The map contains a large pond and notes the seperation between lots 20 and 21. No scale is noted, but chains and inches are being used throughout the description of land. Surveyor notes are seen in pencil on the map. Click on 'detail' to see Map

Welland Canal Survey of Lands William May Jr., 1826

Survey map and description of William May Jr.'s land created by The Welland Canal Company. Included is a written description of the land along with a drawing of the land. The land is described as having 2 good acres and the rest being swamp. The property borders 12 mile creek in Grantham township. Noteable features include; a large pond, division line between lots 20 and 21 as well as 21 and 22, concession line. Surveyor notes are seen in pencil on the map. Click on 'detail' to see Map

Welland Canal Survey of Lands Peter May, 1826

Survey map and description of Peter May's land created by The Welland Canal Company. Included is a written description of the land along with a drawing of the land. Noteable features include; a large pond, the original bed of the 12 Mile Creek. Surveyor notes are seen in pencil on the map. The property is on the second concession in Grantham. Click on 'detail' to see Map